Motor #2

[MarauderMark]

Well since i posted in that other thread everyone keeps pm-ing me asking what happended.Wasn't going to say anything but here it is:
Motor #2's 5000 mile life.Well it was running great for a while there until i took it to the track. Now i have read here that some run there cars below 1/4 tank of gas for more tenths gains.Ok so i asked Dennis about this theroy and he says never run run it below a 1/4 tank.Thats why i asked this question previuosly in this thread::http://www.mercurymarauder.net/forums/showthread.php?t=24936&highlight=low+fuel
So i went to the track with 1/3 tankful of 93 sunoco which is still in the tank and the gauge still reads just above a 1/4 tank and meet Defyant and his friends there for some fun.everything was good went down the first time racing some mustang and turned a 12.6 to the mustangs 13-somethin. Car ran good except for tire spinning on launch and spinning while moving which caused me to let off the go pedal 2 times.Video of the run that did the damage!!! (http://videos.streetfire.net/video/F505D8B6-9459-47F8-8402-A0A623C56797.htm)Car started out great *Clicky here for timeslip* (http://www.mercurymarauder.net/forums/attachment.php?attachmentid=79 73&d=1131764433)Until i got halfway down detonation sat in off went the key until drifted to the end and got towed off the track.Called Dennis as i always do when theres a problem and he said lets get it out and send it back to ron.so Ron calls and says I fried 6 pistons , 2 rods , scored the block and the heads have to have a going over again(all new long block) and all this due to WOT running to lean.so i called Dennis as this was like greek to me and he explained that when on take off the gas rushed to the back of the tank which caused the fuel pumps to run dry since i have an upgraded fuel system(from tank to injectors) therefor to due what it did..Motor was sent out in january and i paid again in full and it seems it going to take another 8 or 9 months to get it back(which was not Dennis's fault the first time ).So this what happened .This is what i'm facing. and whats going on heck , i dont know.Heres my story

[Blackened300a]

So Sorry to hear about your string of bad luck!
Are you 100% sure that letting off the gas and getting back on it would lean it out ot the point of detonation?? Also being that the pump is electric and especially since yours is upgraded and puts out more pressure, Wouldnt that prevent such a disaster?

[HwyCruiser]

Mark, what fuel pump(s) are you running?

EDIT: Nevermind, I checked your link and you list Cobra pumps.

Is there more of a concern with the Cobra pumps? I was talking to a speed shop mechanic and they recommended a modified fuel tank or make sure I had over 1/4 tank of gas too. The Cobra tank is meant to sit flat, where ours sits upright no?

[Joe Walsh]

Mark, What 'tune' were you running and had the new engine combo been tuned on a dyno (with an A/F reading)??

[Hotrauder]

Man, tough Mark. If you were getting detonation before you let off it seems to me to be a tuning problem. I am not a expert by any means but I would be asking some serious questions of people who are. Good luck. Dennis

[snowbird]

Gee, i'm speechless. That's really a bad luck.

Our cars are so complex, it doesn't take much sometimes, to make the worse nightmare come true.

I hope you'll find all answers on what exactly had happened.

[merc]

You could be on to something. You can read the tune and compare the tables, but don't forget to inspect the 02 sensers also.

[MarauderMark]

So Sorry to hear about your string of bad luck!
Are you 100% sure that letting off the gas and getting back on it would lean it out ot the point of detonation?? Also being that the pump is electric and especially since yours is upgraded and puts out more pressure, Wouldnt that prevent such a disaster?
The letting off the gas was on the first run and i did that because the car was spinning tires:burn:
and for your second part i do not know:dunno:





Mark, what fuel pump(s) are you running?

EDIT: Nevermind, I checked your link and you list Cobra pumps.

Is there more of a concern with the Cobra pumps? I was talking to a speed shop mechanic and they recommended a modified fuel tank or make sure I had over 1/4 tank of gas too. The Cobra tank is meant to sit flat, where ours sits upright no?

I have twin focus pumps .I have that answer in the thread link.






Mark, What 'tune' were you running and had the new engine combo been tuned on a dyno (with an A/F reading)??
Here ya go Joe mah bro:up:
http://memimage.cardomain.net/member_images/7/web/487000-487999/487512_93_full.jpg

[MarauderMark]

You could be on to something. You can read the tune and compare the tables, but don't forget to inspect the 02 sensers also.
Ya know i dont have anyone around here to trust touching this car , a bunch money grubbing backwoods types around here so i dont know who could check these things to find out exactly what haapened..

[Blackened300a]

http://memimage.cardomain.net/member_images/7/web/487000-487999/487512_93_full.jpg

May its different on S/Ced engine's then us N/A guys, but my A/F was 13.0 across the board and it was a steady straight line through the entire run. I have seen 2 other N/A Marauders dynoed with the same result. I have no idea what a S/Ced line would look like so yours looks odd to me.

[FordNut]

Now we have more clues...

The fact that the fuel was close to 1/4 tank was probably not the problem.

My car put two rods thru the block during a burnout. I was feathering the throttle. My tuner told me that most likely caused it to go in-and-out of the WOT fuel table. As I have seen on my AFR gauge, when you come out of the WOT fuel table the PCM goes into closed loop control and adjusts for 14.7:1 AFR using the O2 sensor readings. When first letting off the throttle, it commonly goes into "coast" mode and turns off the injectors, in which case I see 18:1 AFR. Getting in and out of the throttle rapidly with a supercharger can put a heavy load on the engine during a lean condition.

I still try to never get on mine hard when lower than 1/4 tank.

Most of the dyno graphs we see are done at WOT and the WOT fuel tables (or MAF transfer functions) are adjusted for 11:1 supercharged or 13:1 naturally aspirated. If the dyno pulls were done at part throttle we would see 14.7:1 AFR. Most dyno graphs show the AFR up close to 14:1 or 15:1 at the beginning, that is when the throttle is stomped and the car transitions to the open loop WOT fuel table.

[MarauderMarc]

Sorry to hear about all this Mark. Youre being a really good sport about it. Id be a wreck if it was me. I hope all works out for ya.

[TooManyFords]

Here ya go Joe mah bro:up:
http://memimage.cardomain.net/member_images/7/web/487000-487999/487512_93_full.jpg

That is a truly ugly A/F tune. When I had mind done, it was absolutely flat at 11.5. And I mean FLAT. However, I still managed to grenade mine too. Turns out the SCT manual recommend cars like ours to run an 11.0 max when running high rwhp numbers.

I am on my second motor and wiser for it.

John

[DEFYANT]

Ok, now that this is done and the secret is out. Lemme add my part.

Mark, FWIW - I want to appologize to you if my "Fastest Marauder yadda yadda yadda" bull***** (dont want to go there) caused you to run the car hard sooner or take the risk of running the car before it was time.

I will keep my opinions to myself since I really have no frikin clue as to what went wrong.

The Race:
You were on your way to an 11 second run though. Folks, When the lights turned green, I had him! Yup! On the green light, I eased into the throttle, that ole supercharger kicked in screamin, headers and exhaust roaring, Nittos clawing for traction, and MarauderMark was in my rear view.

I was all cocky :cool: "Yeah, I got him" and "Wahooo, I'm goin to win"

But at mid track, Mark was back - with vengence. His car walked up along side, and kept walkin. I checked the go pedel.... yup, still on the floor.

Mark passed me by about 3/4 of a car length.

Then he goes and slows down??? I'm thinkin WTF is he doin, he had me. The rear view revealed what was up - smoke! :mad: SMOKE?:bs:

This was a solid 11 second pass! He crossed the finish line slowing down as I was playin catch up - and still won the race!

I am glad you go the car sorted out and passed the info on to the group. Now when are we goin racin again? :burnout:

[bigslim]

I am a firm believer that it was a bad tune, not low fuel that blew your engine. Sorry about the mishap Mark. Hope you have it running soon.

[Rider90]

Sorry to hear of your loss Mark. I noticed you mentioned all this engine stuff was "Like greek to you" IMHO I think it's time to hit the books, or ask around, and learn about it. It's your money, but by now it's one very large investment that I would want to follow around and understand.

Was this a Reinhart tune or did he have someone else do it?

[Blackened300a]

Was this a Reinhart tune or did he have someone else do it?

According to the dyno sheet, It was a Reinhart tune.

[MarauderMark]

Sorry to hear of your loss Mark. I noticed you mentioned all this engine stuff was "Like greek to you" IMHO I think it's time to hit the books, or ask around, and learn about it. It's your money, but by now it's one very large investment that I would want to follow around and understand.
You ain't kiddin.Well since i got this car i have learned alotta things and since this :bs: i am learning more and more.The only poeple i can trust to help me form any opnions are you guys and Dennis as i have no one else.Like i said i don't trust these backwoods workshops around here to touch an expensive car like this let alone ask fer thir informashun abutit.
i laid everything that i know and what happened on the line here to see what ya'll think.:o

[Bluerauder]

Ok, now that this is done and the secret is out. Lemme add my part.

I am glad you go the car sorted out and passed the info on to the group. Now when are we goin racin again? :burnout:
Dang Mark .... I had absolutely no clue about this !!! :( Best of luck in getting this sorted out and fixed. If you need help .... just holler !!!

[MarauderMark]

Ok, now that this is done and the secret is out. Lemme add my part.

Mark, FWIW - I want to appologize to you if my "Fastest Marauder yadda yadda yadda" bull*****

I am glad you go the car sorted out and passed the info on to the group. Now when are we goin racin again? :burnout:
Charlie it was alotta fun just being there with another a$$ kikin Marauderer there .we we're gettin all the looks and talk heck it dont get no better than that:beer:.I may be down and out but i'm commin back with vengence and even more power so keep that title nice and shiney for me:lol: j/k you good people thanks for being there.:up:



Dang Mark .... I had absolutely no clue about this !!! :( Best of luck in getting this sorted out and fixed. If you need help .... just holler !!!
Charlie my ancient brutha :geezer::lol:j/p.Thank you..

[Bluerauder]

Charlie my ancient brutha :geezer::lol:j/p.Thank you..
Man, I went from old to ancient in a week .... :rofl: I gotta go lay down ... :D

[MyTMerc]

Man, I went from old to ancient in a week .... :rofl: I gotta go lay down ... :D

Hasn't Bernie sold that couch yet?

[Smokie]

You ain't kiddin.Well since i got this car i have learned alotta things and since this :bs: i am learning more and more.The only poeple i can trust to help me form any opnions are you guys and Dennis as i have no one else.Like i said i don't trust these backwoods workshops around here to touch an expensive car like this let alone ask fer thir informashun abutit.
i laid everything that i know and what happened on the line here to see what ya'll think.:o

I'm very sorry you went thru this Mark, I looked at your dyno from August/2005 and see nothing really wrong with the A/F ratio, the fluctuations are common when a Wideband sensor is used, it averaged 11.4 across the range, sometimes 11; at about 6k at leaned a bit to about 11.8-11.9, not enough in my opinion to cause a problem.

I looked at the timeslip and I agree with Charlie you were headed to an 11 sec run...that is a fact. I hope everything goes well with rebuild and the reason for the failure can be identified so it can be avoided in the future.