2400 RPM Stall TQ?

[Rider90]

-POST DELETED-

[MERCMAN]

Jason, I am fairly sure that no one will flame you for your lack of knowledge or understanding on this board. There are members here that can answer your question with detail that would amaze an IRS auditor. Unfortunatly, I am not one of them :)

[BillyGman]

What are you some kind of IDIOT???!!! What the :censor: is wrong with you???!!!!!! .......


..uhmm, okay, now for a real answer:D ...... I've seen our stall speed as being listed in the Ford manual as 2,500, but something tells me that's just some kind of guess on their part. I'm sure that it isn't any higher than that though. I used to think that having a stal sped at for instance 3,000 RPM would mean that your car isn't even going to move at all until you rev the engine to that RPM and then suddenly as soon as the revs get to 3,000 the car will jump as if you did a nuetral drop into drive with the shifter. but that's not how it is at all.

All that it means is that full torque will not go through the transmission until that RPM is reached. So yes, having a higher stall speed will allow your car to move quicker off the starting line at full throtle (WOT) but it will NOT feel like you just threw the car into gear from nuetral while reving it. And that goes for whether or not you're at part throttle or WOT. I hope this explanation has helped.

[Rider90]

Well I know what it feels like, having driven that Chevelle before, but I don't want my car to scream like that around town. If we have a 2,500 RPM TC in there now, a 2,400 TC would be useless?

Ours is really 2,500 RPM?

[grampaws]

You sound like your on the right Track..But I just don't

have the experience to give you the best option...Being flamed
for asking questions is just Wrong!!:censor: Isn't that the main
purpose of these boards to help others and pass around ideas..
I'm sure someone here can directyou to the info You need :D

[BillyGman]

Well I know what it feels like, having driven that Chevelle before, but I don't want my car to scream like that around town. If we have a 2,500 RPM TC in there now, a 2,400 TC would be useless?

Ours is really 2,500 RPM?a 2,400 RPM stall speed in a Marauder will not make it anny faster. that's for certain unless ofcourse you have a roots supercharger on it which can make some real good low-end torque. but I don't know if there are any Trilogy customers who have actually tried a 2,400 RPM stall speed. but as for N/A Marauders, a 2,400 RPM stall definately will not improve performance.

[SergntMac]

What are you some kind of IDIOT???!!! What the :censor: is wrong with you???!!!!!!
Hehehe...

My spec sheet for my 300A states the OEM stall is 2800 RPM, 11 1/4 " TC. When I installed a PI Stallion TC in my first MM, I bumped it to 3000 RPM, with no noticable loss of power in routine driving. The performance gain was remarkable, cut my ET .50 or better, still N/A. The key here, is to get as close to your powerband as possible for your launch, and my first MM came on strong at 3500 RPM, while most stock N/A MMs don't get hard until 4000. A 3000 stall Stallion is an excellent mod for the N/A Marauder, it's smaller (9") lighter, and almost twice as efficient as the stock TC.

I bought my second MM already supercharged, and with a Stallion triple plate, 3000 stall. I bumped it to 3500 RPM, and OMG, it's an awesome launch. The triple plate has a split second delay in reaction, but once it does, it's all power to the wheels. Even with my new BFG dral radials in 265/35/18, I'm still traction challenged at the tree, my best 60' time this past weekend was 2.0. I have to work on this, but again, no noticable loss of power in routine driving. If there has been, I've become insensitive to that, it's very driveable, even for non-enthuiasts who have no interest in this stuff.

I can't help you with much advice about your Chevelle, I don't know where the power comes on with the 502. However, traditionally, big block bow ties have a lots of grunt at the low end, so, you shouldn't be concerned. Find the stall that matches your powerband, if your 502 comes on strong at 2400, then a 2400 stall will be fine. If it's 2800, get a 2800 stall, either way, you'll learn to drive it in time.

[BillyGman]

My question is, wouldn't the 3000 stall converter have the same effect on my car RPM wise? what about a 2400 stall converter? noticable, better?:confused:MAC's post has me confused. I'm not saying that his statements about torque converters are wrong, but now I'm not sure if you were asking about a proper stall speed for your Marauder or for that 502 equipped Chevelle. I thought your question was about your Marauder, right? not being sarcastic, but just trying to clarify something here. sometimes comminication through the written word can be difficult and breed misunderstandings. but MAC brought up a good point about a 502 engine being a torque monster with plenty of low-end torque. What I want to add to that is it all depends on what the camshaft specs of that engine are.

For instance, if the cam duration is in the 220-225 degrees( @.050 lift) neighborhood, then that engine is making some fantastic low-end torque and is well served by a lower stall speed than any N/A Marauder would be.But if the cam duration @ .050 lift is in the neighborhood of 240-250 degrees, then it would be better served with a 2,800+RPM stall speed.

As far as the stock stall speed of the 2003 Marauders, the Ford manual says 2,500-3,000 but that's such a broad range that I doubt that they have that correct.

[Rider90]

So get the MM on the Dyno and see when the power band begins to pick up?

[Rider90]

Yes, I am asking about the Marauder but I used the Chevelle as comparison since that is my experience with TC, the Chevelle.

If the stock TC is at 2800 RPM, why would a 3000 make night/day to equal .50 off the 1/4?

[BillyGman]

If the stock TC is at 2800 RPM, why would a 3000 make night/day to equal .50 off the 1/4?I don't think that it would, and that's one reason why I don't belive the Ford manual when it says that our stock stall speed is 2,500-3,000 RPM's. I have a 2003 manual from Ford which is the same one that the Ford dealer service departments use, and that's what it says.

But another possible factor with the Stallion torque converters that many of us Marauder owners opt for, is the claim of the manufacture (Precision Industries) which states that stock converters have a "Torque multiplication ratio" of 1.91:1 while their converters all have a torque multiplication ratio of 2.52:1

So if that's true, then it's possible that increased ratio is also contributing to better launches. that might sound like sales hype, but in light of the fact that my car was .70 seconds faster with the addition of their Stallion Torque converter alone (and that was BEFORE it was supercharged) and their claim is that it will make your car atleast .50 seconds faster, I'm inclined to believe their claims. but you can read it for youself on their website www.converter.com (http://www.converter.com)

from talking with engine tuners, I've learned that stall speeds aren't an exact science. they're simply an estimation. that's due atleast in part to the fact that with any stall speed that you choose, and with any torque converter, the more power you put into it, the higher up in the RPM scale the stall will be. So you can start off with a 3,000 RPM stall speed with an engine churning out 320 FT/LBS of torque, and if you modify that engine w/out touching the torque converter at all, and the engine then is puting out 400 FT/LBS of torque, it will increase the stall speed.

[Bradley G]

I read that a stock MM has a stall speed of 1900 and change.I did a hard hole shot and it seemed that the tack moved to about this(just before 2000RPM)before launching.I was warned by Lidio yesterday that a Stallionconverter is not only not necessary,but will affect daily driveability.He said our converters are good to more power than we would be able to get safely out of our stock internals.He is running a stock converter with a shift kit and of course lots of tuning to make it behave civilized.:twocents:
Bradley G

[Rider90]

I don't think that it would, and that's one reason why I don't belive the Ford manual when it says that our stock stall speed is 2,500-3,000 RPM's. I have a 2003 manual from Ford which is the same one that the Ford dealer service departments use, and that's what it says.

But another possible factor with the Stallion torque converters that many of us Marauder owners opt for, is the claim of the manufacture (Precision Industries) which states that stock converters have a "Torque multiplication ratio" of 1.91:1 while their converters all have a torque multiplication ratio of 2.52:1

So if that's true, then it's possible that increased ratio is also contributing to better launches. that might sound like sales hype, but in light of the fact that my car was .70 seconds faster with the addition of their Stallion Torque converter alone (and that was BEFORE it was supercharged) and their claim is that it will make your car atleast .50 seconds faster, I'm inclined to believe their claims. but you can read it for youself on their website www.converter.com (http://www.converter.com/)

Billy, thank you for your replies. You've been of excellent assistance to my questions. I think the best way to figure this one out is to get a ride in a N/A MM with a stall of 3000 or 3500 to make up my mind. This is something I hope to do "Down the road" when I rack up a couple more paychecks.

If anyone else has valuable info regarding this thread, PLEASE SHARE!!

[BillyGman]

I just edited my [revios post to add to it, so check it out. In addition to that, the Precision Industries tech guy specifically told me over the phone at the time I purchased their stallion converter directly from them (which was about a year and a half ago) that they recommend a 3,000 RPM stall speed for Marauders, and they also told me that if you go any higher than that, you can increase the chances of your transmission runing hotter and decreasing it's life.So that's why I didn't go higher than 3,000 RPM's.(I didn't have the supercharger yet either).


But they have since then changed their advice, and now they state that 3,500 RPM's is okay. I can only guess as to why that is, and I best not speculate here. But that's just the facts according to my telephone conversations with them. You might want to keep that in mind.

[cyclone03]

I'll take a shot at this one......
If your talking about a converter in a Marauder.

I have a PI converter in my MM.
3.55 gears,Kooks and CPU tune.
The stall speed I've seen is about 3500 on launch at the track,on the street the tire just spin.

In 3rd with the converter unlocked at 40mph just holding that speed I see 2000-2200 rpm yes the converter is slipping at that speed and I can see an increase in trans temp too.At 43mph the converter locks and the rpm drops to about 1500.

The WORST slipage I had was with the stock trans programming unlocking the converter in OD at 45 or so MPH. With light throttle the rpm would go to stall (3500) and the car would not pick up any noticable speed.Switching off OD would drop the rpm by 500-700 rpm and the car would excellerate.

With the trans reprogrammed I do not unlock the converter in OD,it shifts to 3rd unlocked then takes off.

[GA-Marauder]

Billy, thank you for your replies. You've been of excellent assistance to my questions. I think the best way to figure this one out is to get a ride in a N/A MM with a stall of 3000 or 3500 to make up my mind. This is something I hope to do "Down the road" when I rack up a couple more paychecks.

If anyone else has valuable info regarding this thread, PLEASE SHARE!!

I have drive TAF's MM, with a 3000 PI converter, and it is a tremendous improvement. Immediate acceleration when demanded, non-intrusive otherwise. I'm having it done to mine in the next couple of weeks, by the guys at Team Ford. They also recommended, as they did with Todd's car, that the transmission be beefed up (shift kit). I'm certainly not an expert, but IMMEDIATELY when I drove Todd's car, I knew that would be my next mod. He is one of the pioneers of mods for our cars, so I trust his choices.

Hope this helps. You might PM him for more info, or maybe he'll chime in here. I believe Marty had the same mod at some point before his supercharger.

[Rider90]

Sure Tony, I'm always looking for more opinions. Thank you

[GA-Marauder]

With the trans reprogrammed I do not unlock the converter in OD,it shifts to 3rd unlocked then takes off.[/QUOTE]

Good point. You will definitely need a tune (chip or flash) to properly manage a new converter.

[Mike M]

Well I know what it feels like, having driven that Chevelle before, but I don't want my car to scream like that around town. If we have a 2,500 RPM TC in there now, a 2,400 TC would be useless?

Ours is really 2,500 RPM?
How are the "second generation" tires as far as traction is concerned? Any difference????

[Rider90]

How are the "second generation" tires as far as traction is concerned? Any difference????

Much better dry traction, and I've just been telling everyone else that the wet traction is "iffy" but keep in mind I only have the rears changed with the OEM fronts - that may contribute to poor wet traction.

[BillyGman]

Good point. You will definitely need a tune (chip or flash) to properly manage a new converter.I don't mean to be argumentative, but just to share my Marauder experience with you, I already had a chip when I bought the Stallion converter, and I was told by the tuner that I didn't need anything differnt done to the chip because of the converter installation. But it might be only because that vendor also sells the Stallion converter too, so he might have already had programming changes for the lock-up burned into the chip to begin with. I dunno.

[SergntMac]

Looks like this is a hot thread today, let's keep it on topic?

I want to address one point of confusion early on. This is a direct quote from Mercury material given to salesmen when the car was released to the public in 2002. Obviously it means to give salesmen sporty answers to questions they may encounter, but it's what I have at my fingertip right now. The document I have is dated "final draft, 02/02/02", maybe something changed?

"Mercury Marauder powertrain engineers have no scruples. They used the transmission from a police car and then improved it further. The transmission is known as 4R70W plus, and features a special brazed turbine/impeller, 11 1/4", 2800 RPM high stall torque converter with a heavy duty truck 1" one way clutch. The plus transmission has the heavy duty gear set from a 5.4L 2V truck".

Okay, moving on.

Yes, I am asking about the Marauder but I used the Chevelle as comparison since that is my experience with TC, the Chevelle. if the stock TC is at 2800 RPM, why would a 3000 make night/day to equal .50 off the 1/4?
Seems Billy and I were both confused, no harm done. If this discussion stays on torque convertors, the tech stuff is the same.

So get the MM on the Dyno and see when the power band begins to pick up?
I would say at this point, save your money on a base line dyno, unless you plan to document every mod for your scrap book. It's been done so much, and with very little variety in results. As you probably know from your dash tach, a stock MM comes on hard and strong around 4000 RPM. A 4000 stall is not the answer here, but other mods can help you pull your power "front door" a bit closer, or, down in RPMs, and then a higher stall will get you closer to that door in your launch. Without tring to turn this into "mods 101", one way is to reduce parasitic drag in the drive line and underdrive pulleys, and a smaller (9") and lighter (by almost 30 pounds) TC contributes to this goal. Help the engine wind up faster and raise your stall, and you'll see major performance gains in your launch.

Billy has covered the internal specs ^ there, the Stallion is a mod that works on the street and track, but you won't see any remarkable improvement on a dyno, because you're not actually pushing the car down the road. I tested both UDPs and the single plate Stallion individually on a dyno, and both produced single digit changes in RWHP and RWTQ. This was disappointing, until I learned more about it, and saw the difference in my ET. The Stallion works, if you want a faster car, this is one way to get there.

the Precision Industries tech guy specifically told me over the phone at the time I purchased their stallion converter directly from them (which was about a year and a half ago) that they recommend a 3,000 RPM stall speed for Marauders, and they also told me that if you go any higher than that, you can increase the chances of your transmission runing hotter and decreasing it's life. So that's why I didn't go higher than 3,000 RPM's.(I didn't have the supercharger yet either). But they have since then changed their advice, and now they state that 3,500 RPM's is okay. I don't know why that is. But that's just the facts according to my telephone conversations with them. You might want to keep that in mind.
You're not wrong, Billy, two years ago, this was their advice. Kenny Brown worked closely with PI while building the Marauder S, and a lot has come to the surface in the background since then.

First, my #1x has the first triple plate TC made by PI. It was an experiment after their single plate failed in testing, running hot and slipping. Back in '02, PI's advice was to not use a single plate on a supercharged application, and they designed the triple plate in it's place. Even then, they had to work out some bugs until things smoothed out, which is why it gets mentioned in Car and Driver's review of my MM, April 2003. Just late last year when I had engine apart for inspection, I sent the triple plate back for a stall change. After 20K of brutal supercharged punishment, the triple plate was in "new, nearly perfect" shape, in Jack's words. I bumped the stall to 3500, and I'm glad I have.

Bradley, I noted you comments from Lidio, and he surely know what he's talking about too. However, so many here have gone the Stallion route with either a stock 2800 stall, or, the 3000, and it has earned it's praise. Like a lot of other mods we discuss, it's a personal choice, and no should shy of having their own opinion on it's value.

I've had both single and triple plate TCs in two cars, one N/A and one S/C. I know the difference in the seat of my pants, on a dyno, and at the track. The Stallion works, if you feel you need to move in that direction. No one has to do anything.

Billy, I don't think you're being argumentive at all. You have been very helpful, I hope you don't think I am disagreeing with you. Paging through my scrapbook, if you bought a chip from Reinhart before the TC, there were no programming changes to lock-up. If you bought the TC first, then a chip, it should have been programmed to lock up after the 2-3 shift, at least as I recall it. But, this was back in '02 when lot's of ideas were being tried, and many did not like the difference in lock-up, so, it's just an option to consider. Personally, I liked it the first option, after the 2-3 shift, Lidio's settings are killing my MPG.

[HwyCruiser]

Hmmm, now that I have a Diablo tune, where the only time the locks is after the OD shift + 2 mph (about 47 mph), I'm starting to wish I had Jerry W.'s converter lockup schedule back. Dennis had fixed this for me right after I had the PI Stallion installed and discovered I had the 2nd gear WOT pause while the old program was locking the converter so I didn't have much experience with what it is doing now.

With the converter unlocked in 1st, 2nd, & 3rd gear and lifting off the throttle, the rpm drops around 800-1000 and dips and bobs a couple of times until it finds some sort of equilibrium. With Jerry W.'s converter lockup schedule, the converter would lock up at approx 40 mph in 3rd and stay locked until the rpms dropped enough to cause a downshift or you got into the pedal enough to cause it to unlock. The transitions just felt right.

Once the TC was locked, lifting off the gas caused very little rpm drop but the speed would reduce by engine braking. Some have discribed it as driving a manual transmission and lifting your foot off the gas with the clutch still engaged. I liked that quite a bit since most of my driving in the city took advantage of this cycle.

The only negative was the feeling of an extra "shift" when the converter locked at 40 mph, but now I feel that its a good trade to get rid of the rpm fluctuations. I always wondered what Dave (MI2QWK4U) was talking about with weird idle flucuations with a "loose" torque converter and now I know.

I think there's a lot of personal preference involved in the TC lockup behavior especially noticeable with a loose converter such as the Stallion. This is something I plan on working on with a local Diablo tuner to get squared away for my own personal preference.

[Bradley G]

Thanks Mac,

As usual, you get into the nuts and bolts on topic.
I guess like our new Prez,I need to drive one maybe at the low end 2400stall and up if the opportunity presents itself.
My only hesisation besides the expense(got to be real)is the driveability.
My wife drives it daily( for now at least)I have already had comments with my modest modslike,"what did you do to the car?"
Especially when it was geared lower and no tune was done
I like to cruise regular a lot of the time and really enjoy the well manered behavior that I have now.
The other, is the last thing you mention is MPG .As I said earlier I get real close to 25 MPG highway and this makes for a good Range for trips(usually the bladder goes first:rolleyes: )And with age I see this only getting worse! LOL
enough of my rambleings.Carry on.
Bradley G

[Rider90]

Thanks Mac,

As usual, you get into the nuts and bolts on topic.
I guess like our new Prez,I need to drive one maybe at the low end 2400stall and up if the opportunity presents itself.
My only hesisation besides the expense(got to be real)is the driveability.
My wife drives it daily( for now at least)I have already had comments with my modest modslike,"what did you do to the car?"
Especially when it was geared lower and no tune was done
I like to cruise regular a lot of the time and really enjoy the well manered behavior that I have now.
The other, is the last thing you mention is MPG .As I said earlier I get real close to 25 MPG highway and this makes for a good Range for trips(usually the bladder goes first:rolleyes: )And with age I see this only getting worse! LOL
enough of my rambleings.Carry on.
Bradley G

Brad, in the Chicken Run thread I asked any N/A 3000 stall MMs if I could get a ride...we'll see if there are any in the first place too :D

[Bradley G]

Thanks for those comments,

This is exactly what Lidio was eluding to when he gave me advice yesterday.
I rarely notice the lockup all of you guys talk about.He claimed with the triple plate you may not be happy with this alone with out more tweaking/tuning.
I am not sure it is because of Lidio's prefrences with his stock (performance) tune, or wether I am not understanding how the car performs in relation to what the trans is doing.
Maybe I should drive with someone that fully understands, by the cars behavior what exactly lockup is and how it feels .
I am very pleased with the tune except the quick 1-2 shift at part throttle and sometimes it does not want to downshift 2-1 at certain Tweener speeds and appears to lug in the higher gear for a bit.
Thanks for you feedback
Bradley G
Hmmm, now that I have a Diablo tune, where the only time the locks is after the OD shift + 2 mph (about 47 mph), I'm starting to wish I had Jerry W.'s converter lockup schedule back. Dennis had fixed this for me right after I had the PI Stallion installed and discovered I had the 2nd gear WOT pause while the old program was locking the converter so I didn't have much experience with what it is doing now.

With the converter unlocked in 1st, 2nd, & 3rd gear and lifting off the throttle, the rpm drops around 800-1000 and dips and bobs a couple of times until it finds some sort of equilibrium. With Jerry W.'s converter lockup schedule, the converter would lock up at approx 40 mph in 3rd and stay locked until the rpms dropped enough to cause a downshift or you got into the pedal enough to cause it to unlock. The transitions just felt right.

Once the TC was locked, lifting off the gas caused very little rpm drop but the speed would reduce by engine braking. Some have discribed it as driving a manual transmission and lifting your foot off the gas with the clutch still engaged. I liked that quite a bit since most of my driving in the city took advantage of this cycle.

The only negative was the feeling of an extra "shift" when the converter locked at 40 mph, but now I feel that its a good trade to get rid of the rpm fluctuations. I always wondered what Dave (MI2QWK4U) was talking about with weird idle flucuations with a "loose" torque converter and now I know.

I think there's a lot of personal preference involved in the TC lockup behavior especially noticeable with a loose converter such as the Stallion. This is something I plan on working on with a local Diablo tuner to get squared away for my own personal preference.

[Bradley G]

Thanks for those comments,

This is exactly what Lidio was eluding to when he gave me advice yesterday.
I rarely notice the lockup all of you guys talk about.I am not sure it is because of Lidio's prefrences with his stock (performance) tune, or wether I am not understanding how the car performs in relation to what the trans is doing.Maybe I should drive with someone that fully understands, by the cars behavior what exactly lockup is and how it feels .I am very pleased with the tune except the quick 1-2 shift at part throttle and sometimes it does not want to downshift 2-1 at certain Tweener speeds and appears to lug in the higher gear for a bit Thanks for you feedback
Bradley GPS good luck on getting squared away with your tune HwyCruiser!

[GA-Marauder]

I don't mean to be argumentative, but just to share my Marauder experience with you, I already had a chip when I bought the Stallion converter, and I was told by the tuner that I didn't need anything differnt done to the chip because of the converter installation. But it might be only because that vendor also sells the Stallion converter too, so he might have already had programming changes for the lock-up burned into the chip to begin with. I dunno.
Naw, that's ok. I'm really just passing along the advise I was given by the Team Ford transmission guys. I'm already chipped, and they mentioned I would need to get together with Aric (our local tuner) to remap my current program. I'm just going with exactly the same tune he gave to TAF, who has the same setup that I will in the next couple of weeks. I'm just learning this stuff, so any info in very valuable to me.
Thanks:up:

[SergntMac]

With the converter unlocked in 1st, 2nd, & 3rd gear and lifting off the throttle, the rpm drops around 800-1000 and dips and bobs a couple of times until it finds some sort of equilibrium.

With Jerry W.'s converter lockup schedule, the converter would lock up at approx 40 mph in 3rd and stay locked until the rpms dropped enough to cause a downshift or you got into the pedal enough to cause it to unlock. The transitions just felt right.

Once the TC was locked, lifting off the gas caused very little rpm drop but the speed would reduce by engine braking. Some have discribed it as driving a manual transmission and lifting your foot off the gas with the clutch still engaged. I liked that quite a bit since most of my driving in the city took advantage of this cycle.
Yep...What I had a few tunes ago, and I wish I could get it back. Easier on gas, brake pads, and the exhaust rumble was neat too.

Bradley, when you find a Marauder with a 2400 stall, call me? I'd love to test drive it too.

[Gagfish]

Per Ford, the stock converter is a 2300 RPM unit manufactured for Ford by B & M. Ironically, before my Marauder I bought one to swap into my 2v T-Bird. Now I have the 3000 RPM PI in the Marauder.

3000 in the Marauder is great for launches and does not effect around town drivability with the exception of less "creep".

[Bradley G]

I spoke to Five O last weekend at Cedar Falls.He is S/C'ed you probably know Trilogys' kit small pulley(2.8) Stallion triple plate, MT slicks.
I race in the other lane from him, for my first run of the evening.
I had him, till the tree turned Green:o :D His car was already warmed up!
Bradley G
Yep...What I had a few tunes ago, and I wish I could get it back. Easier on gas, brake pads, and the exhaust rumble was neat too.

Bradley, when you find a Marauder with a 2400 stall, call me? I'd love to test drive it too.

[Bradley G]

Ya! That creep you mention keeps me from rolling up close to someone at a light or stop sign.

Bradley G


Per Ford, the stock converter is a 2300 RPM unit manufactured for Ford by B & M. Ironically, before my Marauder I bought one to swap into my 2v T-Bird. Now I have the 3000 RPM PI in the Marauder.

3000 in the Marauder is great for launches and does not effect around town drivability with the exception of less "creep".

[SergntMac]

Per Ford, the stock converter is a 2300 RPM unit manufactured for Ford by B & M. Ironically, before my Marauder I bought one to swap into my 2v T-Bird. Now I have the 3000 RPM PI in the Marauder.
Can you reveal a bit more about what "Per Ford" means? Who said so, or, how you learned this...Website with specs maybe? I ask only because I have documentation here from L/M, with a publication date. I'd like to know if it's changed, I don't like sharing stale data, it doesn't help anyone. Please tell me more?

[Gagfish]

Dan Newman is my Ford parts guy and he really knows his parts. When I got my 4v 11" 2300 stall converter for my T-Bird from him it was $140. So when I saw that the PI was $700 I called Dan to look into it a bit to see if there was a comprable Ford unit. Ford does not offer a 3000 stall unit, the highest they make is the 2300 which is what is stock on the Marauder and what I put in the T-Bird. He also checked in his B & M catalog as he told me they manufactur the Ford converters but they do not mke one either.

2800 may have been the "planned" stall speed but what they actually produced was less. There would not be much of a difference in 2800 vs. 3000.

[Rider90]

Thank you for sharing gagfish

[Captain Steve]

This thread got me interested in how the TC and automatic transmission in our cars work.

Here's a couple of neat links.

http://auto.howstuffworks.com/torque-converter.htm
http://auto.howstuffworks.com/automatic-transmission.htm


When somebody is talking about the TC "locking up" what they are saying is that the clutch in the TC is activated, and the engine is then directly connected to the transmission.. like a manual cars clutch. This is what allows a modern automatic to get decent mileage on the highway.. Overdrive and a locked TC.



After reading the article on automatic transmissions, I finally figured out what people were talking about when they mentioned the "OD band" It's litterally a band of metal that works like an oil wrench, to stop part of the planetary gear from spinning.. producing the OD gear ratio. NEAT STUFF! :banana:

[Glenn]

Save up your money and just go with the S/C. That's exactly what I wish I had done 2 years ago. Your MM only needs ONE mod that is a S/C. I have the benefit of the tremendous accumulated knowledge contained on this net at this point in time, but not when I bought my MM. I installed a great deal of mods including the PI TC 3000 which does indeed reduce your ET by 0.50 second as advertised, but none of these mods are really needed if you have the S/C. Just save your money and go with the S/C your stock TC and gears will work fine.

Glenn

[SergntMac]

Y'all just hang on, more 411 rolling in on this topic.

[mpearce]

I find this thread very interesting, and would like to know alot more on this subject. When everyone mentions "stall" or "stall speed" what inside the torque conv. exactly is stalling? When you all relate the torque conv. stall speed (i.e. 3000, 3500) to your launch, and getting it close to your power band...what exactly is going on? What sort of benefit does this have?

My torque conv. is stock, and this past weekend at the Cleveland meet, I got a chance to drive Cruztakers MM for an extended period of time. The difference off the line was incredible compared to my MM. The car seemed to be able to just jump off the line effortlessly. I know Cruz's got a lot of major mods done, Kooks, etc. but I have a feeling lot of that "jump" had to do with his torque conv. Unfortunately, I don't know what stall he's got.

I was very impressed with the way it felt, and would certianly like to have mine like that as well. What sort of difference is there between a 3000, and 3500 stall torque conv.?

[Captain Steve]

I find this thread very interesting, and would like to know alot more on this subject. When everyone mentions "stall" or "stall speed" what inside the torque conv. exactly is stalling? When you all relate the torque conv. stall speed (i.e. 3000, 3500) to your launch, and getting it close to your power band...what exactly is going on? What sort of benefit does this have?

My torque conv. is stock, and this past weekend at the Cleveland meet, I got a chance to drive Cruztakers MM for an extended period of time. The difference off the line was incredible compared to my MM. The car seemed to be able to just jump off the line effortlessly. I know Cruz's got a lot of major mods done, Kooks, etc. but I have a feeling lot of that "jump" had to do with his torque conv. Unfortunately, I don't know what stall he's got.

I was very impressed with the way it felt, and would certianly like to have mine like that as well. What sort of difference is there between a 3000, and 3500 stall torque conv.?From http://www.converter.com/q1.htm


STALL SPEED
Torque converter stall is a commonly used term and is commonly misunderstood. Stall is the speed at which the converter will hold the engine speed and not allow further gain (i.e., the engine "stalls"). The key word here is engine. The speed at which stall occurs with a given converter is a function of engine peak torque. It is clear that the stall speed on a given converter will not be the same coupled to a tame small block engine when compared to a big block with all of the muscle features added. When comparing stall speeds it is important to account for the engine that drives it. True converter stall can best be determined when a Transbrake is used. Testing for stall value by locking the wheel brakes generally does not produce a true stall value because the engine power can often cause wheel turn by overpowering the brakes. Stall speed determined by this method should be identified as such when discussing stall speed determination. Flash stall is determined by launching at full throttle and observing the peak speed attained at launch. Selection of the right stall speed for your vehicle should be matched to the engine peak torque, engine torque curve shape and vehicle weight. In general, the stall speed selected for your converter would be 500 to 700 rpm below the peak torque. This speed allows the margin for application of the torque reserve on takeoff. When selecting stall speed without having prior experience to go by, it is better to conservatively estimate the engine torque than it is to over estimate it. If you over estimate the torque output you will have a converter with a stall speed too low, making your car slow off the line and have slow ET. A properly selected stall speed will give you better launch and better ET. You can see why it is important to consult with professionals prior to making a stall speed selection. Within the converter, stall speed is balanced off against inefficiency after launch. Getting desired stall at the expense of performance after launch is just as costly as improper stall speed to begin. The optimum converter has careful selection and design of changes to the impeller, turbine and stator.

[GA-Marauder]

I got a chance to drive Cruztakers MM for an extended period of time. The difference off the line was incredible compared to my MM. The car seemed to be able to just jump off the line effortlessly. I know Cruz's got a lot of major mods done, Kooks, etc. but I have a feeling lot of that "jump" had to do with his torque conv. Unfortunately, I don't know what stall he's got.

I was very impressed with the way it felt, and would certianly like to have mine like that as well.
My impression also after driving TAF's car. It is the torque converter, and it makes the car seem 1000 pounds lighter. Acceleration is instantaneous. I do believe, that next to a S/C, this is probably one of the biggest mods in terms of seat of the pants feel that there is. That's why I'm having it done in the next couple of weeks. T/C is on order. Can't wait!:banana:

[Bradley G]

I have been coresponding with Jack From PI, on this subject.
My objective, is to get a better launch & /ET's without changing drivability(Too Much)
I don't want to sound too much like a weenie,My wife drives the MM over fifty miles stop and go for work.
I cringe when she askes me," What did you do to the car now?"
When I changed to 4:10's and didn't have the tuner changed immediatly,this was the first time I remember her saying this.
After a JLT CAI (cone filter), I heard it again "How come the car is louder now?"
She even asked me,( after installing UD pullies & PHP spacer) a few weeks ago, "The car seems peppier!,What did you do to it now?"
I don't get away with much ,It appears:o .
And back on topic, Jack from PI said, "If you don't want her(wife)to complain,go with a 2800 stall" "She probably won't complain, too much!"
BTW within two years of purchace,PI will change your stall speed for no charge .
Thanks for listening!
Bradley G

[sailsmen]

I had a PI 3,000 for 20+K miles and it does not affect driveability. I now have a 3,500.

Only difference is to back up you got to give it some gas, but of those 40K miles only 1 mile or less has been in reverse! :D

[mpearce]

From http://www.converter.com/q1.htm
Thanks for that reply Captain Steve. I will now quote something from that post...

("In general, the stall speed selected for your converter would be 500 to 700 rpm below the peak torque. This speed allows the margin for application of the torque reserve on takeoff.")

Ok...so would you then look at your cars dyno graph, look for the peak TQ RPM number, and go from there?

Running some numbers off my dyno graph, my MM's peak TQ was at 4200 RPM.

4200 - 500 = 3700

or

4200 - 700 = 3500

So going by this would I select a 3500 stall T/C?

Just curious here, thats all. Just wondering why some go with the 3000 stall, and some go with the 3500 stall.

Also...Ive heard some say that a 3000/3500 stall with a blower isn't needed because of all the extra HP and TQ associated with the blower. Are there cons to having a 3000, or 3500 stall TQ with a blower?

Just curious, no flames meant.

-Mat

[Rider90]

This thread is awesome.

Carry on :popcorn:

[Rider90]

I found an interesting thread searching...

http://www.mercurymarauder.net/forums/showthread.php?t=15484&page=1

[SergntMac]

Dan Newman is my Ford parts guy and he really knows his parts. When I got my 4v 11" 2300 stall converter for my T-Bird from him it was $140. So when I saw that the PI was $700 I called Dan to look into it a bit to see if there was a comprable Ford unit. Ford does not offer a 3000 stall unit, the highest they make is the 2300 which is what is stock on the Marauder and what I put in the T-Bird. He also checked in his B & M catalog as he told me they manufactur the Ford converters but they do not mke one either. 2800 may have been the "planned" stall speed but what they actually produced was less. There would not be much of a difference in 2800 vs. 3000.B&M is not big enough to supply Ford with torque converters, can you imagine how many TCs this would be, in one year of world wide sales? The supplier of TCs is www.lukusa.com (http://www.lukusa.com), with almost ten production plants world wide. You'll find their brand "LuK" somewhere on your TC. Ford doesn't offer an 11" TC, they only come in 11.25" and 12.0" What ever Dan Neuman sold you for your 4V TBird, must have come from B&M. I agree that 2800 vs 3000 doesn't sound like a lot, but that not the reason to buy a PI in the first place. The rational is first, higher torque conversion and efficiency, and second, 9.5" TC vs 11.25 " TC, loosing about 30 pounds of parasitic drag from the drive line. Those two factors alone, justify the PI. Pick any stall you want.