Any Interest in Upgraded FPDMs for High Amp FPs?

[RacerX]

For those staying returnless, I'm testing modified FPDMs that will take up to 25a instead of the stock 18a before thermal shutdown. My own FPDM went into thermal shutdown at the track this past Summer. With a high current draw fuel pump and upgraded wiring to it, the weak point is now the driver module, esp. in warm weather. Transistors, toroidal inductor and capacitor are upgraded. Thinking of offering these at a decent price with a core return.

Stock:

http://www.mercurymarauder.net/gallery/data/579/medium/IMG_1353a.jpg (javascript:;)

Modified:

http://www.mercurymarauder.net/gallery/data/579/medium/IMG_1352a.jpg (javascript:;)

Side by Side:

http://www.mercurymarauder.net/gallery/data/579/medium/IMG_1354a.jpg?3710 (javascript:;)

Yes Ken, we're doing yours too. ;)

[guspech750]

Ohhhhhh. More goodies to spend money on!!


Sent from The White House on taxpayers dimes.

DTR + 4.10's + Eaton swap = Wreeeeeeeeeeeeeeedom

[Limited360]

I was debating on doing this but I don't see much of a need running a stock pump still... however if I go up in boost at all the 45-47% duty cycle (90 to 94% real) I see now means I will require a new pump...

Glad I know whom to contact now about this at least!

[MyBlackBeasts]

For those staying returnless, I'm testing modified FPDMs that will take up to 25a instead of the stock 18a before thermal shutdown. My own FPDM went into thermal shutdown at the track this past Summer. With a high current draw fuel pump and upgraded wiring to it, the weak point is now the driver module, esp. in warm weather. Transistors, toroidal inductor and capacitor are upgraded. Thinking of offering these at a decent price with a core return

Interested!

Who is doing the actual circuit board work?

Wasn't sure by your description if it is your work or if you are having done.

Price point estimation yet?

Thnx! :D

[RacerX]

My father and I. He's a highly qualified EE. Worked on many govt weapons programs and lots of civi stuff. Some in space. ;)
Price should be around $60 with core or $90 without. That's not set in stone yet. This is still in testing phase.

[Limited360]

My father and I. He's a highly qualified EE. Worked on many govt weapons programs and lots of civi stuff. Some in space. ;)
Price should be around $60 with core or $90 without. That's not set in stone yet. This is still in testing phase.


Sounds like a reasonable price point if it pans out... look forward to send you mine just to be safe....

Yes I am that guy!

[Comin' in Hot]

I'm down for one, possibly two

[MyBlackBeasts]

My father and I. He's a highly qualified EE. Worked on many govt weapons programs and lots of civi stuff. Some in space. ;)
Price should be around $60 with core or $90 without. That's not set in stone yet. This is still in testing phase.

Very interested. Can you post a hi-res pic of the CB backside? I'd like to zoom in and inspect solder work.

I think you are on to a very good mod for the mm.net community (not to mention the rest of the Panther community).

Thank you! :up:

[RacerX]

Modified on the left, stock/untouched on the right. My work on this one if it's ugly. ;)
Thanks. http://www.mercurymarauder.net/gallery/showfull.php?photo=23410

http://www.mercurymarauder.net/gallery/data/579/medium/IMG_1355a.jpg (http://javascript<b></b>:;)

[MyBlackBeasts]

Modified on the left, stock/untouched on the right

Looks good!

Subscribing & 1st in line (ok, maybe 4th) for one! :D

[lifespeed]

Very interesting. I'm not yet at the point of installing a blower which would prompt a fuel system upgrade. But from what I have read so far I know I am not interested in a boost-a-pump module (too much of a hack IMHO), but would like to retain the factory returnless control system. Indeed, in California, it would probably not be negotiable anyway.

So all that is required is a decent returnless fuel pump, heavy gauge wires to carry the current without voltage drop, and . . . a fuel pump controller module that can supply more current.

[RacerX]

Correct! I will be dropping my BAP soon also.

[Spectragod]

I'd be interested in the parts or a source to buy them, I have a shop at my disposal for such projects.

[boatmangc]

MMmmm dilythium crystals :drool:

Subscribing

[Limited360]

I'd be interested in the parts or a source to buy them, I have a shop at my disposal for such projects.


Yeah I've got an electrical lab at the office I can use whenever, for $60 I'll let ya make a buck! :)


Sent from my iPhone using Tapatalk (http://tapatalk.com/m?id=1) so I may sound retarded.

[fastblackmerc]

I'd be interested in one.

[Spectragod]

Yeah I've got an electrical lab at the office I can use whenever, for $60 I'll let ya make a buck! :)


Sent from my iPhone using Tapatalk (http://tapatalk.com/m?id=1) so I may sound retarded.

I only care to make 1 for me, I have other project that pay my bills.:rolleyes:

[JBeezy]

I'm Interested. Installed the aeromotive 340 pump amd BAP with no wiring upgrades, so this wouldn't hurt.


Sent from my iPhone using Tapatalk (http://tapatalk.com/m?id=1)

[lifespeed]

I'm Interested. Installed the aeromotive 340 pump amd BAP with no wiring upgrades, so this wouldn't hurt.

You would want to upgrade wire gauge as you'll still get voltage drop. Can't fight the laws of physics.

[Vortech347]

I'm Interested. Installed the aeromotive 340 pump amd BAP with no wiring upgrades, so this wouldn't hurt.


Sent from my iPhone using Tapatalk (http://tapatalk.com/m?id=1)

Since you have a returnless where voltage varies you may be okay but if that pump was ran full bore like a return style I guarantee your factory wires would be a melted mess right now.

Upgrade the wires ASAP!

[JBeezy]

Are you talking upgrade wire gauge from BAP to pump? I have an 8 gauge from my battery to the trunk. Then a 10 gauge from a distribution block to my BAP


Sent from my iPhone using Tapatalk (http://tapatalk.com/m?id=1)

[RacerX]

Yes, to the pump. This is the main current draw. It's important when you upgrade to a 340lph, 400lph or to a twin pump setup keeping the FPDM to upgrade the wire to the pump itself also.

[Mike M]

I have been in thermal shutdown a few times this summer and I bought a modified FPDM, I would like to buy another as a backup so put me down for one.

[MOTOWN]

You would want to upgrade wire gauge as you'll still get voltage drop. Can't fight the laws of physics.

Exactly!!!!!!!!!!!!

[jwibbity]

ill take one for down the road upgrades, can't up the boost without addressing the fuel system

[massacre]

Well I am return-style but just wanted to say it's great to see you making these Bill!
You are always thinking lol.

[burt ragio]

Sounds like a winner. If all goes as expected with your testing put me down for one.

[MM2003SC]

Put me on list as well.

[Limited360]

I will take one if this goes down as I will need to upgrade my fuel system to add the optical port in my block...

[RacerX]

Cool, I will keep this thread updated as it progresses. I may need a tester in a warmer climate than I'm in to proof it in a track environment.


I will take one if this goes down as I will need to upgrade my fuel system to add the optical port in my block...

Optical ports in blocks are no good unless:
1. You're slomo filming and studying flame front physics
2. You're using advanced high power laser technology for ignition instead of plugs.
3. You're dumping so much fuel and air in that you want to visually watch hydrolock.

:D

[Limited360]

Cool, I will keep this thread updated as it progresses. I may need a tester in a warmer climate than I'm in to proof it in a track environment.



Optical ports in blocks are no good unless:
1. You're slomo filming and studying flame front physics
2. You're using advanced high power laser technology for ignition instead of plugs.
3. You're dumping so much fuel and air in that you want to visually watch hydrolock.

:D


I just figure its a good reason to install the forged aluminum motor I need to get building...

[JoeBoomz]

Nice job Bill, keep up the good work.

I am probably doing a return system in the next year, sick of the inherent delays in the returnless system.

[lifespeed]

I am probably doing a return system in the next year, sick of the inherent delays in the returnless system.

Would you elaborate on this?

[dmjarosz]

I am interested

Oh yeah and, subscribed!

[Vortech347]

Would you elaborate on this?

While not as common in Auto'd cars because you don't lift to shift the manual cars have a hell of a time with lift shifting at high RPM. What happens is the fuel pumps are hauling ass at 6500rpm. You lift to shift and in that short time frame the computer reads a spike in pressure. Then telling the FPDM "Full stop!!!!" By that time you have rowed the shifter lifted the clutch and mashed the go pedal again. Now you have the pumps damn near OFF and open the injectors again to full flow. This obviously creates a horrible lean spike where the car falls on its face as if you hit a damn curb.

It can actually be mostly tuned out by clipping the pressure and a few other changes in the tune but to be completely gone you either need to #1, Powershift and keep the right foot to the floor or be at least 1/2-3/4 throttle during the shift (easy with auto cars) Or #2, go return style.

I would think in a Marauder with an eaton the returnless would catch up fast enough with the time it takes doing a transmission kick down. I've never even noticed the returnless glitches/problems in my Marauders. But they have all been N/A

[jwibbity]

hurry up and make these so you can take my money!!

[RacerX]

hurry up and make these so you can take my money!!

After Xmas, I'll be ramping up. I do need someone in a warmer climate with a high draw fuel pump that goes to the track to test this. Because it is a thermal issue, I want actual hot weather track testing done. It won't warm up here for a bit. :rolleyes:

[RacerX]

Ok! Testing phase is done!!! Three FPDMs were thoroughly tested. Stock/OEM, another vendor's modified FPDM that's been out for a while and the one's my father and I are building. The stock/OEM FPDM drops 1.5v and the electronics hit 256° at a sustained high load within minutes. Once shut off, this FPDM will not power on again until it has cooled some. Thermal shutdown! The other vendors hits 234° and drops .74v. This one did not go into thermal shutdown running @ over 20 amps for an hour. OURS drops only .52v and hit only 170° after an hour. We have designed this to take 30 amps for up to a 15+ (that should cover everyone!) second run! We'll be building more in the next two weeks. Ken's car (NH Muscle) will have the first one. I'll take cores for a discount also.

[justbob]

While not as common in Auto'd cars because you don't lift to shift the manual cars have a hell of a time with lift shifting at high RPM. What happens is the fuel pumps are hauling ass at 6500rpm. You lift to shift and in that short time frame the computer reads a spike in pressure. Then telling the FPDM "Full stop!!!!" By that time you have rowed the shifter lifted the clutch and mashed the go pedal again. Now you have the pumps damn near OFF and open the injectors again to full flow. This obviously creates a horrible lean spike where the car falls on its face as if you hit a damn curb.

It can actually be mostly tuned out by clipping the pressure and a few other changes in the tune but to be completely gone you either need to #1, Powershift and keep the right foot to the floor or be at least 1/2-3/4 throttle during the shift (easy with auto cars) Or #2, go return style.

I would think in a Marauder with an eaton the returnless would catch up fast enough with the time it takes doing a transmission kick down. I've never even noticed the returnless glitches/problems in my Marauders. But they have all been N/A

Been there a few times already.


After Xmas, I'll be ramping up. I do need someone in a warmer climate with a high draw fuel pump that goes to the track to test this. Because it is a thermal issue, I want actual hot weather track testing done. It won't warm up here for a bit. :rolleyes:

Warm here soon and off to the track. After throwing my parts of my driveshaft at the M3 I passed, needless to say I will trailering from now on.. So failure IS an option! :)
I'll take one.



Self proclaimed Builder Of Badassery.

Buy it, Break it, Build it BETTER.
"Since 2004"

[Mike M]

Yes I want one.

[RacerX]

If I keep this up, I'm going to need a trailer! Now, how to het the wife to believe I need a Raptor to pull it... Hmmm..

Cool! I'll give you a heads up as soon as I have them ready to ship. Should be about April 2nd to 3rd. :beer:

[Joe Walsh]

I picked up a spare Marauder FPDM at the junkyard a few years ago....I'm in for getting it upgraded.

[RacerX]

Buy one modified FPDM $90.00
Buy one, send in your core $90.00 and $30.00 back when I receive core.
If you send them to me, I'll mod them for $60.00. One week turn around.
PM me if interested.
Thanks!

[ctrlraven]

I wonder if it would be wise to do one for my new NA setup.

[Limited360]

Buy one modified FPDM $90.00
Buy one, send in your core $90.00 and $30.00 back when I receive core.
If you send them to me, I'll mod them for $60.00. One week turn around.
PM me if interested.
Thanks!


Great deal!

I plan on buying one from you and sending mine in :)

After Louisville when I start doing other mods!


Sent from my iPhone using Tapatalk so I may sound retarded.

[blkZooM]

thinking about running two of these with a dual fpdm, only thing that stopped me was the price. Let me know when you will start to offer these

just saw you have the price up already, will be contacting you soon.

[RacerX]

I have them ready. They work great! :D

[MyBlackBeasts]

I have them ready. They work great! :D

How much $ and when can I get one?

[JBeezy]

PM sent

Sent from my SAMSUNG-SGH-I337 using Tapatalk

[blkZooM]

Ready to send in two of mine for to you to mod, can you pm me your address.

[Paul]

Received mine Friday. Thanks Bill, looking forward to running with it. :)

[RacerX]

http://www.mercurymarauder.net/gallery/data/727/medium/Modifying_FPDMs.jpg

http://www.mercurymarauder.net/gallery/data/727/medium/Modifying_FPDMs_2.jpg

[nh muscle]

Do you have one to control the wife??

[RacerX]

Do you have one to control the wife??

http://gripshot.net/shop/images/704/taser_x26c.jpg

[nh muscle]

Lol when can you ship it?

[screamn]

I'm interested & you have a PM sir.

[parker]

I am interested and sent a PM with no response.
Also anyone know what the "I" and the "R" means on the cover? I see all have an "I" except one that has an "R".


Sent from my iPhone using Tapatalk

[RacerX]

All PMs replied to. The internal electronics and circuit boards are exactly the same no matter what is on the covers for labels. FLM used these on a broad array of vehicles. :beer:

[sexygomer]

Woohoo! I remembered seeing this post a while ago, and hoped I wasn't raising the dead. Is it too late to add my name as a potential client?

[RacerX]

Woohoo! I remembered seeing this post a while ago, and hoped I wasn't raising the dead. Is it too late to add my name as a potential client?

Any time! I have them ready to ship. :beer: I have them in 20+ Marauders and a few Ponies.

[Vortech347]

Would this benefit my Terminator? I'm running stock pumps with a 40amp BAP and an 8 gauge wired relay pre-FPDM. I don't necessarily have any issues with the current setup but if I decide to get brave and throw a 4lb lower on obviously I'll be taxing things further.

[martyo]

I sent you a PM.

[RacerX]

Would this benefit my Terminator? I'm running stock pumps with a 40amp BAP and an 8 gauge wired relay pre-FPDM. I don't necessarily have any issues with the current setup but if I decide to get brave and throw a 4lb lower on obviously I'll be taxing things further.

Yes! These modified FPDMs are more efficient and will actually lower the voltage necessary to drive the fuel pumps. In conjunction with the wiring upgrade, you'll find you have more safety overhead on fuel pump duty cycle. These are actually better than Black306s!


I sent you a PM.

Thank you once again Marty!

[martyo]

Yes!



Thank you once again Marty!

Always happy to give you the business.

[tbone]

Subscribing. PM sent.

[RacerX]

Back at you!

[tbone]

Thanks Bill!

[lifespeed]

PM sent, need one of these.

[Lowndex]

My father and I. He's a highly qualified EE. Worked on many govt weapons programs and lots of civi stuff. Some in space. ;)
Price should be around $60 with core or $90 without. That's not set in stone yet. This is still in testing phase.

I am interest in buy a new one from you, please.

[RacerX]

PM sent, need one of these.

Back at ya!


I am interest in buy a new one from you, please.

PM'd!

[tbone]

Yes! These modified FPDMs are more efficient and will actually lower the voltage necessary to drive the fuel pumps. In conjunction with the wiring upgrade, you'll find you have more safety overhead on fuel pump duty cycle. These are actually better than Black306s!


I missed this part. Do you recommend upgrading the wiring with a single Aeromotive 340 and your mod? Or, if I went back to my Walbro 255 and turned on my Boost-a-Pump, would I need it? I had a couple burps in my fuel delivery a few days ago. Been fine since. May have had a little water in the tank. Not sure what happened.

[RacerX]

Doing the wiring upgrade allows more current/less resistance to run the pump. It will help no matter what you run. A 340, modified FPDM and wiring upgrade is a really good combo. That's what my buddy Ken (nh muscle) is running right now in his SB Marauder. He just hit over 550rwhp on the rollers.

[parker]

Doing the wiring upgrade allows more current/less resistance to run the pump. It will help no matter what you run. A 340, modified FPDM and wiring upgrade is a really good combo. That's what my buddy Ken (nh muscle) is running right now in his SB Marauder. He just hit over 550rwhp on the rollers.



What do you mean by wiring upgrade?

[RacerX]

What do you mean by wiring upgrade?
You literally upgrade the wiring to the FPDM and FP with larger gauge wiring.
Here's a writeup/instuctions from Lethal Performance on it:

http://www.lethalperformance.com/downloads/dl/file/id/77/lethal_performance_bap_fpdm_wi re_upgrade_kit_instructions.pd f

Wiring kits (or you can just do your own):

http://www.lethalperformance.com/lethal-performance-fpdm-bap-wiring-upgrade-kit.html

http://www.wmsracing.com/wmsweb/wms-fpdm-dual-fuel-pump-driver.html

http://www.lastcallracing.com/z5-fpdm-stage2.html

[parker]

You literally upgrade the wiring to the FPDM and FP with larger gauge wiring.
Here's a writeup/instuctions from Lethal Performance on it:

http://www.lethalperformance.com/downloads/dl/file/id/77/lethal_performance_bap_fpdm_wi re_upgrade_kit_instructions.pd f

Wiring kits (or you can just do your own):

http://www.lethalperformance.com/lethal-performance-fpdm-bap-wiring-upgrade-kit.html

http://www.wmsracing.com/wmsweb/wms-fpdm-dual-fuel-pump-driver.html

http://www.lastcallracing.com/z5-fpdm-stage2.html



Thanks bud

[lifespeed]

You literally upgrade the wiring to the FPDM and FP with larger gauge wiring.

What gauge is the stock wire?

[RacerX]

What gauge is the stock wire?

Errrr... lol, I don't remember exactly. I do know it's pretty light gauge for the higher current draw on the bigger pumps. I went with 8 gauge when I did mine. I also have it changed in my tune to NOT turn off the alternator at WOT. :D

[lifespeed]

Errrr... lol, I don't remember exactly. I do know it's pretty light gauge for the higher current draw on the bigger pumps. I went with 8 gauge when I did mine. I also have it changed in my tune to NOT turn off the alternator at WOT. :D

Does this include the wire from FPDM to the pump as well? It is shorter, so less voltage drop. Might still exceed the temperature rating of the insulation.

20' of 10G wire drops 0.7V at 17A (Walbro 400) so 8G is not wasted effort. If the pump has margin against the fuel requirement a little voltage drop may not hurt, but if you're going to run the wire anyway . . .

It is difficult to move power in a 12V system. Eventually cars will have 48V electrical.

[tbone]

Bill - Remember when I first got your modded FPDM, the pump went dead soon after and you had me switch relays 201 and 203? Well, today I got stranded again. Pump was dead and I had to switch the relays around several times until I found one that finally fired up the pump. I went over to O'Reillys and got a new relay and it seems to be ok. I thought these relays were 20 amp, but after research it looks like they are all 30 amp. Do they simply get weak over time? Not blaming you at all, but I had no issues with relays until I got the modded FPDM and I need some insight into what may be going on here.
Thanks!

[fastblackmerc]

Bill - Remember when I first got your modded FPDM, the pump went dead soon after and you had me switch relays 201 and 203? Well, today I got stranded again. Pump was dead and I had to switch the relays around several times until I found one that finally fired up the pump. I went over to O'Reillys and got a new relay and it seems to be ok. I thought these relays were 20 amp, but after research it looks like they are all 30 amp. Do they simply get weak over time? Not blaming you at all, but I had no issues with relays until I got the modded FPDM and I need some insight into what may be going on here.
Thanks!

Relays do get weak over time and the contacts get pitted, just like the relay in the LCM.

I replaced all mine with the 40A relay I use in my LCM upgrade / fix. You can get the same relay in 50/60 & 80A.

[tbone]

Is a new 30 amp sufficient or should I go even higher?

Where did you get yours? Best price? I paid $15.99 at O'Reillys. I wouldn't mind replacing them all after reading your post.

[RacerX]

The wiring upgrade will get rid of this issue!

[tbone]

Are you saying if I don't do the wiring upgrade it will be a persistent issue?

I can get 6 relays for $28 shipped on ebay. Not sure of the quality......

[fastblackmerc]

Is a new 30 amp sufficient or should I go even higher?

Where did you get yours? Best price? I paid $15.99 at O'Reillys. I wouldn't mind replacing them all after reading your post.

They are just a Bosch-style relay, nothing special. You may have to cut the mounting tab off or remove the tab if it's metal.

I can get 60A relays for $5.50 each.

[lifespeed]

Are you saying if I don't do the wiring upgrade it will be a persistent issue?

I can get 6 relays for $28 shipped on ebay. Not sure of the quality......

The wiring upgrade bypasses the high current supply around the factory relay using a heavy gauge wire and a dedicated relay installed in the trunk, triggered by the OEM fuel pump relay. So yeah, it will keep the factory fuel pump relay from burning out because it only carries enough current to drive the auxiliary relay you added.

I wouldn't shop for relays on fleabay, don't know why so many people are enamored of that site. Good place to get counterfeit Chinese garbage. Use Mouser or Digi-key.

I'm not sure how much current the OEM fuel pump circuit is intended to carry, but with a constant power device like a fuel pump it will draw more current as the voltage drops. So if the factory wiring is dropping significant voltage it would increase the current draw. It is conceivable you could overload the circuit this way. Want to check? Put a voltmeter at the input to the FPDM and measure the voltage. The problem is you need to do this check when the fuel pump is running hard, so this is a slightly awkward full throttle test. Unless there is a way to command the pump to full on using tuning software.

[tbone]

They are just a Bosch-style relay, nothing special. You may have to cut the mounting tab off or remove the tab if it's metal.

I can get 60A relays for $5.50 each.


Where do you get them?

[tbone]

The wiring upgrade bypasses the high current supply around the factory relay using a heavy gauge wire and a dedicated relay installed in the trunk, triggered by the OEM fuel pump relay. So yeah, it will keep the factory fuel pump relay from burning out because it only carries enough current to drive the auxiliary relay you added.

I wouldn't shop for relays on fleabay, don't know why so many people are enamored of that site. Good place to get counterfeit Chinese garbage. Use Mouser or Digi-key.

I'm not sure how much current the OEM fuel pump circuit is intended to carry, but with a constant power device like a fuel pump it will draw more current as the voltage drops. So if the factory wiring is dropping significant voltage it would increase the current draw. It is conceivable you could overload the circuit this way. Want to check? Put a voltmeter at the input to the FPDM and measure the voltage. The problem is you need to do this check when the fuel pump is running hard, so this is a slightly awkward full throttle test. Unless there is a way to command the pump to full on using tuning software.

Thanks for the explanation. :)

The factory relays aren't really "burned out". When I switched 201 and 203 per Bill's instructions after my fuel pump went down, the horn still worked. It burped a couple times the other day, then the complete shutdown again today. IDK

[tbone]

The relays I found on ebay for $4.67 each shipped are the same exact ones on Amazon for $15.95 each, which is what I paid today at O'Reillys for a 30 amp. I Googled Ford's part number and not much variety to choose from shows up. Not even OEM Ford. Everything is made in China.

The 5 pin mini relays on RockAuto for instance are all 20 amp. What is the amperage of the stock relays? They don't say on them or in the owner's manual. I'm betting 20 amp. I upgraded the mini fuse from 20 to 30 amp when I supercharged per instructions from the group. Therefore the stock relay would be the weak link, no?

I remember a highly respected member on here emphatically stating that the wiring upgrade is a waste of money, so I cancelled my order from Lethal a while back.

[tbone]

The Airtex/Wells 20 amp on RockAuto lists for $3.65.

https://www.rockauto.com/en/catalog/mercury,2003,marauder,4.6l+v8, 1387829,electrical-switch+&+relay,fuel+pump+/+circuit+opening+relay,3380

[lifespeed]

Thanks for the explanation. :)

The factory relays aren't really "burned out". When I switched 201 and 203 per Bill's instructions after my fuel pump went down, the horn still worked. It burped a couple times the other day, then the complete shutdown again today. IDK

Relays can be intermittent, and the contacts can burn. I wouldn't necessarily conclude the relay is OK.


I remember a highly respected member on here emphatically stating that the wiring upgrade is a waste of money, so I cancelled my order from Lethal a while back.

Some things are only learned through experience and the school of hard knocks. Some things can be calculated. Fuel required per horsepower, for example. Then there are the gray areas.

But voltage drop you should be able to calculate (http://www.calculator.net/voltage-drop-calculator.html?material=coppe r&wiresize=5.211&voltage=12&phase=dc&noofconductor=1&distance=20&distanceunit=feet&amperes=17&x=32&y=14) and measure. The question is what gauge wire do we have? Some fuel pumps specify their performance at 13.5V and 12V, giving you an idea of how they'll perform with some wiring losses.

If you're on the hairy edge of pump performance the wiring upgrade may put you in the safe zone. If you have plenty of margin, some voltage drop probably won't hurt.

[tbone]

I ordered 6 - 20amp Airtex from RockAuto. Since I had to hunt for a relay to get my car running it's time to just replace them all.

The ebay specials were only 10 amp. I'm glad I emailed the vendor before I ordered.
So I saved a couple bucks and got twice the service rating and a 3 year warranty.

If I have another issue with my 30 amp relay, I will upgrade the wiring fosho.

[RacerX]

Are you saying if I don't do the wiring upgrade it will be a persistent issue?

I can get 6 relays for $28 shipped on ebay. Not sure of the quality......

You're the third person to have this issue out of thirty marauders and a few ponies with my FPDM. It may be that yours and the others have a dirty connection somewhere causing the issues. The wiring upgrade totally bypasses this relay.

[lifespeed]

I think I'll change the fuel pump relay as well. No need to find out about it when the engine quits.

[tbone]

You're the third person to have this issue out of thirty marauders and a few ponies with my FPDM. It may be that yours and the others have a dirty connection somewhere causing the issues. The wiring upgrade totally bypasses this relay.

I think my old, worn out 20 amp relay(s) is the culprit. My new 30 amp should fix it. I'm going to put it through its paces today. What's the point of switching the fuse from 20 to 30 amp if you leave the relay at 20?

[tbone]

I think I'll change the fuel pump relay as well. No need to find out about it when the engine quits.

The worst part is that I had just shown a Subaru WRX driver the pure awesomeness of my Marauder's supercharger and Magnaflows. He was then behind me at the light and I hit it.....limped about 100 feet and I had to pull over. He blew by me with his fart can sputtering. GDI :mad2:

[fastblackmerc]

I think my old, worn out 20 amp relay(s) is the culprit. My new 30 amp should fix it. I'm going to put it through its paces today.

As these cars age the relays will become weaker and weaker as they are electro-mechanical. The contacts will also degrade. Easy and cheap fix is to replace them all occasionally. Just like doing preventative maintenance on other parts and systems.

[tbone]

As these cars age the relays will become weaker and weaker as they are electro-mechanical. Easy and cheap fix is to replace them all occasionally. Just like doing preventative maintenance on other parts and systems.

I think the proof is in the fact that I had to switch around the relays 3 or 4 times before I finally found one that would fire up the pump.

My 6 replacements shipped from RockAuto this am.

[Spectragod]

I think my old, worn out 20 amp relay(s) is the culprit. My new 30 amp should fix it. I'm going to put it through its paces today. What's the point of switching the fuse from 20 to 30 amp if you leave the relay at 20?



So your going to use a 30 amp relay on a 20 amp circuit? I'll wait for the "my car caught on fire" post.

If your going to up the amperage of the relays, the wiring should correspond with the mod. Or you could just say **** it and bypass all the fuses and relays. Your call.....

[lifespeed]

So your going to use a 30 amp relay on a 20 amp circuit? I'll wait for the "my car caught on fire" post.

If your going to up the amperage of the relays, the wiring should correspond with the mod. Or you could just say **** it and bypass all the fuses and relays. Your call.....

There is nothing wrong with increasing the size of the relay, it is the fuse and wire gauge that have to match.

But you are right to pay attention to these details.

[Spectragod]

There is nothing wrong with increasing the size of the relay, it is the fuse and wire gauge that have to match.

But you are right to pay attention to these details.



There's -0- point to having a 30 amp relay on a circuit that is fused and wired for 20 amp operation.

[lifespeed]

What's the point of switching the fuse from 20 to 30 amp if you leave the relay at 20?

Are you blowing 20A fuses? Which fuel pump? That doesn't sound right. It is unsafe to put a 30A fuse on wiring designed for 20A.

[lifespeed]

There's -0- point to having a 30 amp relay on a circuit that is fused and wired for 20 amp operation.

If the 20A relay were built correctly with design margin, sure. But there is a lot of crap out there, and putting in a larger relay will generally provide more durable contacts and a longer lifespan when the circuit is operating close to the rated limit. I'll bet those LCM relays are rated for the design current, but they didn't last.

I think it is reasonable to use a larger relay.

[Spectragod]

Are you blowing 20A fuses? Which fuel pump? That doesn't sound right. It is unsafe to put a 30A fuse on wiring designed for 20A.



He didn't say he was blowing fuses, but, there is no electrical benefit to go to a bigger relay if the wiring hasn't been upgraded, and the fuse size.

Personally, I'd wire a stand alone relay in, triggered by the OE 20 amp unit.

[Spectragod]

If the 20A relay were built correctly with design margin, sure. But there is a lot of crap out there, and putting in a larger relay will generally provide more durable contacts and a longer lifespan when the circuit is operating close to the rated limit. I'll bet those LCM relays are rated for the design current, but they didn't last.

I think it is reasonable to use a larger relay.



I have pictures of cars/houses that have burnt to the ground because someone thought that exact way. More current and not supporting wiring and/or fuses.

I say go for it, what can go wrong?

[lifespeed]

He didn't say he was blowing fuses, but, there is no electrical benefit to go to a bigger relay if the wiring hasn't been upgraded, and the fuse size.

Personally, I'd wire a stand alone relay in, triggered by the OE 20 amp unit.

If the 20A relay burned, by definition it has an issue and isn't doing the job well. A larger relay would have more margin.

I would measure voltage at the FPDM input. A current measurement is probably not necessary if the 20A fuse isn't blown. Whether larger wiring is needed can be objectively determined.

[tbone]

If you look at the Kenne Bell instructions, it specifically states to upgrade the 20 amp fuse to a 30 amp. No problems with that in 2 years.

I just got back from driving around for an hour with about 15 full throttle passes and no issues at all. Believe me, I thought about the wiring issue and possible fire. But again, why would it be recommended to upgrade the FUSE to 30 amp if it were such a dangerous proposition?

[lifespeed]

I have pictures of cars/houses that have burnt to the ground because someone thought that exact way. More current and not supporting wiring and/or fuses.

I say go for it, what can go wrong?

What? Where did I say to run the circuit beyond it's rating? Installing a larger relay has nothing to do with the current in the circuit. You're mixing up circuit protection with electromechanical switches.

There is never a downside or safety issue with oversizing wiring, relays, switches, etc. The danger comes with installing a larger fuse or circuit breaker on an undersized circuit.

[lifespeed]

If you look at the Eaton swap instructions, it specifically states to upgrade the 20 amp fuse to a 30 amp. No problems with that in 2 years.

I just got back from driving around for an hour with about 15 full throttle passes and no issues at all. Believe me, I thought about the wiring issue and possible fire. But again, why would it be recommended to upgrade the FUSE to 30 amp if it were such a dangerous proposition?

It may not be dangerous. That wire looked like it was either 10G or 12G. One can't easily tell because insulation thickness is uncertain, so how thick is the wire? I didn't want to strip off the insulation to find out.

12G wire is safe at 30A, it won't melt. The circuit was probably fused for a reasonable pump max current, not to keep the (10G, 12G?) wire from melting. With 12V systems the wire needs to be sized larger for voltage drop reasons, which puts it well above the safety rating for temperature vs current.

Upsizing the wiring to the fuel pump is done to reduce voltage drop and get more power to the pump, not because the wire is in danger of melting. If you drive your pump with 12.3V instead of 13.5V you have made your pump "smaller".

[tbone]

It's not like the pump is pulling 30 amps the entire time the car is running. And if it gets over 20, it is only for a short time under heavy load.

The Kenne Bell Boost-a-pump instructions advise to upgrade the fuse from 20 to 30 amp. I highly doubt these expert custom car parts builders/suppliers would advise that if there was even the slightest chance of "burning a car to the ground". They can't afford the liability. Besides, once the relay simply completes the circuit, the fuse it what protects the wiring from overload.

Read instruction #10. Replace 20 amp fuel pump fuse with 30 amp.

[tbone]

There's -0- point to having a 30 amp relay on a circuit that is fused and wired for 20 amp operation.

But it's not so that's the point. See above.

I appreciate your input but sarcasm is not necessary. (Post 98, 104)

[Spectragod]

But it's not so that's the point. See above.

I appreciate your input but sarcasm is not necessary. (Post 98, 104)



That wasn't sarcasm, it's your car, do as you choose. As I said, I would run a separate circuit and switch that relay with the output of the OE relay.

[fastblackmerc]

Installing a higher amperage relay will not cause any harm. The relay will still pass whatever voltage / amperage is passed to it. The higher amperage relay will last longer due to the heavier duty parts inside. Your circuit will still be protected by whatever circuit breaker or fuses in installed.

Never ever install a higher amperage fuse in a circuit designed for a smaller amperage fuse.

[Spectragod]

Installing a higher amperage relay will not cause any harm. The relay will still pass whatever voltage / amperage is passed to it. The higher amperage relay will last longer due to the heavier duty parts inside. Your circuit will still be protected by whatever circuit breaker or fuses in installed.



Never ever install a higher amperage fuse in a circuit designed for a smaller amperage fuse.



You are correct. But. It is a useless upgrade unless you can guarantee that the cheap relay you just bought off Amazon or eBay is better than what your replacing.

And. If your trying to do an upgrade, then the whole circuit needs the attention, not just the relay.

It would be like using race fuel in a car with a 93 tune, pointless.

[fastblackmerc]

You are correct. But. It is a useless upgrade unless you can guarantee that the cheap relay you just bought off Amazon or eBay is better than what your replacing.

And. If your trying to do an upgrade, then the whole circuit needs the attention, not just the relay.

It would be like using race fuel in a car with a 93 tune, pointless.

I'm replacing mine with Tyco relays.

[lifespeed]

I'm replacing mine with Tyco relays.

Would you post a link?

[Spectragod]

I'm replacing mine with Tyco relays.



Those will work......

[tbone]

You are correct. But. It is a useless upgrade unless you can guarantee that the cheap relay you just bought off Amazon or eBay is better than what your replacing.

And. If your trying to do an upgrade, then the whole circuit needs the attention, not just the relay.

It would be like using race fuel in a car with a 93 tune, pointless.

I replaced the 30 amp fuel pump relay with a fine quality MasterPro from O'Reillys. The rest are 20 amp Airtex/Wells from RockAuto. If my a/c compressor or fog lights stop working I'll be sure and let you know.....

I notice you choose to ignore my post quoting Kenne Bell about upgrading the pump fuse to 30 amp. Interesting. I guess you know more than one of the most highly regarded high performance parts builders in the business.

[tbone]

Never ever install a higher amperage fuse in a circuit designed for a smaller amperage fuse.

Unless Kenne Bell says it's ok. ;)

[RacerX]

Never ever install a higher amperage fuse in a circuit designed for a smaller amperage fuse.

This applies to all electrical circuits in anything. Unless of course you're working on circuitry for an Iranian nuclear facility, then it's ok! :P

[Spectragod]

I replaced the 30 amp fuel pump relay with a fine quality MasterPro from O'Reillys. The rest are 20 amp Airtex/Wells from RockAuto. If my a/c compressor or fog lights stop working I'll be sure and let you know.....

I notice you choose to ignore my post quoting Kenne Bell about upgrading the pump fuse to 30 amp. Interesting. I guess you know more than one of the most highly regarded high performance parts builders in the business.



I didn't choose to ignore it, I posted between things while at work. My honest opinion, I wouldn't do it because kenne bell says to. Just because he says to do it doesn't make it right, ohms law is all that matters in this case. You can do what ever you want, it is your car, I merely made a recommendation.

The bottom line, if FOMOCO didn't factor in the additional load and make the circuit capable of handling the additional draw, then you will have a problem. The main reason there is a voltage drop front to rear is because the wire being used is already incapable of supporting the draw you are placing on it, so by putting in a bigger fuse and relay, what would you suppose the outcome will be?

I can tell you, it will work for a while. And cheap China made relays are not going to make things better.

[BigCars4Ever]

I don't know what you changed in your upgraded FPDM but if the cap got bigger and the inductor got smaller (lower inductance and lower resistance) then ther initial current through the relay when the contacts first close could have increased significantly which would stress an older relay. Just a thought.

[lifespeed]

I don't know what you changed in your upgraded FPDM but if the cap got bigger and the inductor got smaller (lower inductance and lower resistance) then ther initial current through the relay when the contacts first close could have increased significantly which would stress an older relay. Just a thought.

Yes, it could surge more at startup and will be a little harder on the relay. Some PWM circuits have a soft-start function, don't know about the modded FPDM.

Bigger relay can't hurt.

[tbone]

I didn't choose to ignore it, I posted between things while at work. My honest opinion, I wouldn't do it because kenne bell says to. Just because he says to do it doesn't make it right, ohms law is all that matters in this case. You can do what ever you want, it is your car, I merely made a recommendation.

The bottom line, if FOMOCO didn't factor in the additional load and make the circuit capable of handling the additional draw, then you will have a problem. The main reason there is a voltage drop front to rear is because the wire being used is already incapable of supporting the draw you are placing on it, so by putting in a bigger fuse and relay, what would you suppose the outcome will be?

I can tell you, it will work for a while. And cheap China made relays are not going to make things better.

1. I haven't had a problem in 2 years with a 30 amp pump fuse as recommended by KB.

2. You don't draw a constant 30 amp from the pump.

3. I trust Kenne Bell recommendations over yours any day.

4. We have all already told you that the relay size doesn't matter, the fuse size does. So that reasoning has been made invalid numerous times.

5. Do you really think the relays made for Ford in 2003 weren't already "Made in China". That excuse is getting really, really old.

6. You didn't just make a recommendation. You implied I would burn my car to the ground in a sarcastic manner if I didn't follow your opinions.

7. If you don't have the time at work to read the posts completely and make thoughtful posts, don't do it.

8. I'm willing to bet that the parts RacerX uses to do his FPDM mods are "Made in China". He will correct me if I am wrong.

9. Have a nice day. :)

[Spectragod]

1. I haven't had a problem in 2 years with a 30 amp pump fuse as recommended by KB.

2. You don't draw a constant 30 amp from the pump.

3. I trust Kenne Bell recommendations over yours any day.

4. We have all already told you that the relay size doesn't matter, the fuse size does. So that reasoning has been made invalid numerous times.

5. Do you really think the relays made for Ford in 2003 weren't already "Made in China". That excuse is getting really, really old.

6. You didn't just make a recommendation. You implied I would burn my car to the ground in a sarcastic manner if I didn't follow your opinions.

7. If you don't have the time at work to read the posts completely and make thoughtful posts, don't do it.

8. I'm willing to bet that the parts RacerX uses to do his FPDM mods are "Made in China". He will correct me if I am wrong.

9. Have a nice day. :)



You clearly know more about car, electrical and reading my mind knowing that what I posted was sarcasm instead of advice.

I'm done, as I said, it's your car do as you please.

[Bradley G]

I have this one now, I will need another if more than 450 rwhp. is achievable.
http://www.blueovalchips.com/index.php?l=product_detail&p=270
Since Just bob diagnosed my stock pump at almost max duty cycle, back in the day, I went to this pump^^that is the only fuel issue I have ever had.

[RacerX]

^^This is why I went on this endevour. I had two GT40 FPs and a KB BAP installed. My FPDM would kick into thermal shutdown at the track in the summer. We did a lot of research and found we could make a modified FPDM that was better than what was out there and inexpensive. :beer:

[Bradley G]

I do whatever Lonnie says, not that I think in anyway, that you would do different.
I do remember him telling me the next step in power, was going to require quite a bit, due to being close to the threshold now.
I guessing, if I want over 450 RWHP ,I'll need one.


^^This is why I went on this endevour. I had two GT40 FPs and a KB BAP installed. My FPDM would kick into thermal shutdown at the track in the summer. We did a lot of research and found we could make a modified FPDM that was better than what was out there and inexpensive. :beer:

[fastblackmerc]

Would you post a link?

http://www.parts-express.com/te-connectivity-tyco-electronics-12-vdc-5-pin-relay-spdt-20-30a-%28formerly-bosch%29--330-070

http://www.amazon.com/Metra-Install-123-Bay-Relay/dp/B000P61E36

You will have to cut the tab off and shave down the bosses on the side.

[Spectragod]

Here's a couple of sources that require tolerances on the parts they resell, not cheap like eBay and Amazon, but you get what you pay for. Tessco even sells a 50 amp relay, gotta be better, it's rated at more amperage....

https://www.tessco.com/products/displayProductInfo.do?sku=3610 57

http://www.ctwinc.com/relays.htm

[RacerX]

All right, enough. The relay size can be one that's rated equal to or above the circuit it's opening and closing. Installing a larger relay just allows it to pass a larger current through it. The important part is keeping the correct fuse in said circuit. That's critical! The relay manufacturer is important also. There is a lot of cheap crap out there that does not stand up to normal use or wear. I had one on my heat exchanger pump circuit that rotted out in less than a year. Get quality and make sure it's sealed if it's exposed to the elements. These mods can be great when done right. For twin pumps, an upgraded FPDM and the wiring upgrade are fantastic. This mod has been done for years successfully in the high hp pony community that wanted to stay returnless.

[Spectragod]

All right, enough. The relay size can be one that's rated equal to or above the circuit it's opening and closing. Installing a larger relay just allows it to pass a larger current through it. The important part is keeping the correct fuse in said circuit. That's critical! The relay manufacturer is important also. There is a lot of cheap crap out there that does not stand up to normal use or wear. I had one on my heat exchanger pump circuit that rotted out in less than a year. Get quality and make sure it's sealed if it's exposed to the elements. These mods can be great when done right. For twin pumps, an upgraded FPDM and the wiring upgrade are fantastic. This mod has been done for years successfully in the high hp pony community that wanted to stay returnless.

Sorry for the derail, but I have seen the result of not upgrading ALL components, and tried to enlighten some, but I hit a brick wall.

While a larger relay will pass more current, i.e. amperage, in order for there to be more amperage, there has to be a larger fuse or breaker, hence the problem, if the rating of the wire is less than adequate. While a car built by an individual or customizer may be overbuilt, from the factory, they are built to be as cost effective for the manufacturer as possible, read barely adequate in this spot.


Your enhanced driver is a great upgrade, well built and cost effective, certainly a good mod for boosted vehicles.

[RacerX]

Anyhoo... Entertainment aside, I'm doing two more Marauder FPDMs this weekend.

[cer0413]

Long shot but I need one.

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[Spectragod]

Long shot but I need one.

Sent from my SM-G930P using Tapatalk



I have one


Sent from my iPhone while doing a big ole' smokey burnout in my wife's Prius.

[cer0413]

I have one


Sent from my iPhone while doing a big ole' smokey burnout in my wife's Prius.
Check your pm

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