Burned a piston BAD!!! BIG pics (long)

[11secGLH]

Hi great site here, I plan to be a regular. The car is an 85 GLH, just converted it to T2 (fresh chrysler reman long block) and 88 electronics. It has a ported +1mm G head, 1 piece intake I modified heavily, and a ported exhaust manifold. T2 Roller cam, TU S60 turbo, 3" swingvalve and exhaust, A555. For fuel I have the 255 pump, AFPR, +40's, 3 bar map, MP S60 computer (just until TU cals come up again). I have a cheap but good ebay intercooler, 2.5" piping and Turbonetics BOV. I also did the #4 coolant mod.

I have worked at Dodge dealerships since 1986, built literally thousands of engines so I know these cars and what they will and won't take pretty good. This wasn't it. It started and ran great, I had my Innovate LM1 and snap on scanner on it and everything looked good. My A/F was 13.5 at light throttle/cruise, 15.0 on decel and 11.5 part throttle, 10 psi. I was driving it pretty easy for about 30 miles and then gave it a few short light throttle 10psi shots. After about 6 of those it developed a miss which got worse real quick so I pulled it apart. This is what I found:
http://www.pix8.net/pro/pic/17716kNIl5/759810.jpg
http://www.pix8.net/pro/pic/17716kNIl5/759811.jpg
http://www.pix8.net/pro/pic/17716kNIl5/759812.jpg

To me, it doesn't look like detonation it is TORCHED like no fuel. So I send out the injectors to get tested and they are good (118cc!!!) If the computer didn't fire the injector, there would have been 2 cylinders with problems because of the batch fire setup. I tested all the injector wires and they are good.The only other thing I can think of is the G head doesnt like the timing of the S60 computer? I'm sure there was no vac leaks as it idled well with good vacuum.

There is metal transfer to the block so it is toast. Not the end of the world but I want to make sure this doesn't happen again. I bought Wiseco forged pistons for some extra insurance and an EGT guage. Any thoughts or suggestions are appreciated.

I cut the top and elbow off the intake and the front half of the runners were milled down an inch or so. The center between 2&3 was milled out and inverted. We welded a 3" tube across the top, capping one end flat and a 3" cast elbow on the other end, blending everything in first. Here are the pics:http://www.pix8.net/pro/pic/17716kNIl5/759818.jpg
http://www.pix8.net/pro/pic/17716kNIl5/759819.jpg
http://www.pix8.net/pro/pic/17716kNIl5/759821.jpg
http://www.pix8.net/pro/pic/17716kNIl5/759822.jpg

[John B]

The cutting torch effect is clasic pre-ignition. You may have had a clogged injector. Been there.:( Nice work on the intake!:thumb:

[GLHSKEN]

Also.. The broken land is classic detonation. The torch would not have taken out the lands so effectivle.

Fuel pump getting weak??

[glhs875]

I don't know what the timing curve is on the S60 computer, but the 88 electronics was set up for the swirl head and has less total timing under boost than a cal designed for a swirl head or even an 86 cal. My stock cal on my 88 Daytona had a total advance of 22 degrees by 10 to 12 psi of boost (12deg. base + 10deg from the computer). The 86 cal has around 27 degrees total at the same boost level. What Iam getting at is with a G head that needs more timing advance than a swirl to work properly, the EGT's may have gotten to high due to not enough timing advance under boost, which could have led to a destructive process. I know for a fact that only a couple of degrees of timing can affect EGT's alot. Seen it with my own eyes using datalogging equipment. And if the timing is the cause of the problem, adding fuel will only make the problem worse and raise EGT's even higher. You'll just be adding fuel to the fire so to speak.

[GLHSKEN]

S60 must be agressive as heck.. It's a race gas only cal. Also, The 86 cals were for swirl heads.

Yes, A "G" headed car needs more timing. Which CYL went?? Did it have an EGT in it?? Is it possible there is uneven airflow through the intake causing a lean condition in a cyl??

[glhs875]

S60 must be agressive as heck.. It's a race gas only cal. Also, The 86 cals were for swirl heads.

Yes, A "G" headed car needs more timing. Which CYL went?? Did it have an EGT in it?? Is it possible there is uneven airflow through the intake causing a lean condition in a cyl??

I know the 86 cal is for a swirl head that was part of my point. Too little timing would be more apt to burn a piston rather than just crack it. Although too little or too much timing could both cause cracking of pistons due to the high EGT temps heating something up and acting like a torch igniting the fuel to soon from the timing being too low. I'm not familar at all with the S60 cal, but would like to know what total timing it has under different boost levels. I agree the intake could be a problem if has a wide enough air distribution problem. I don't know his whole set up, so Iam only putting out SOME possibilties to try and help.

[GLHSKEN]

LOL... I think we've given him plenty... One thing I've learned with these cars.. just when you think you have it covered.. oops...

Reeves is running about 15^ base in his 2.5L tII piston G head car. His egt's are 1700+... No matter what the fuel. But if we add any more timing right now, it knocks.

I'm really thinking your sds set-up might be the way to go... Then we control it all.

[John B]

I would think that the large plenum would even out air delivery more if anything.

[11secGLH]

The fuel pump (and almost everything else) is brand new. I use premium (94) gas. The S60 cal has 2 settings, the low setting and a race only setting. It was #4 that went. I didnt have an EGT guage then but I have one now. Thanks for the replies, keep em coming, Chris.

[turbovanman²]

Looking at the pics, I would say detonation killed it. You can see the cracks at the ring lands, which would make sense as the added heat would go by the cracks and melt the piston. I have melted a few motors and no cracked lands. Also, what kind of pistons did the block have? Stock Cast Mahles or Hypers? I would agree with Ken, the S60 is supposed to have an aggressive spark curve, what did you set the base timing at and what octane fuel were you running? Oh, what cylinder was that?

[glhs875]

LOL... I think we've given him plenty... One thing I've learned with these cars.. just when you think you have it covered.. oops...

Reeves is running about 15^ base in his 2.5L tII piston G head car. His egt's are 1700+... No matter what the fuel. But if we add any more timing right now, it knocks.

I'm really thinking your sds set-up might be the way to go... Then we control it all.


Is that 15deg. base or 15deg. total timing?

[glhs875]

I'm really thinking your sds set-up might be the way to go... Then we control it all.[/QUOTE]

A person can definitely squeeze out more & safer power out of a programable set up. Unless you get lucky and have a cal that is dead on for a certain combo. That would be rare! Although if a cal was done at a dyno or at the track, it could be dialed in alot better.

[11secGLH]

They were stock cast Mahle's, #4. Was using 94 octane. I'd like to stress that the engine was driven very easy, and it made 10psi at part throttle. The timing I had was 12 base.

[cordes]

I am not sure about the S60 cals, but aren't most of the stock cals supplying verry little fuel at part throttle?

I think Una would be able to give a better run down, but 10 PSI part throttle with the agressive timing of the S60 cal could cause a problem for sure.

[turbovanman²]

94 octane sounds too low. I stand my my detonation that killed it. I would redo it and give it less base timing.

[11secGLH]

If detonation killed it because of low octane, all the cylinders would show signs. The rest are all perfect. I'm not saying it wasn't detonation, but detonation due to low octane, the car would've run real bad, knocked and took out more than one cylinder.Don't you think?

[turbovanman²]

If detonation killed it because of low octane, all the cylinders would show signs. The rest are all perfect. I'm not saying it wasn't detonation, but detonation due to low octane, the car would've run real bad, knocked and took out more than one cylinder.Don't you think?

Not really, I cracked one piston in my van and I didn't hear the rap until it was too late.

I know you said you bought a reman Mopar engine but it could have hyper pistons, or some inferior quality ones, you just never know!

[GLHSKEN]

+1... not every cylinder will be affected at the same time. Eventually there is a good possibilty. And the part throttle issue brought up was a good one...

[8valves]

It's the part throttle that killed it more than likely. I'm guessing you didn't get to see the LM1 readings when you were under the "spiritied part throttle" if you will. Chances are they leaned out pretty bad. Part throttle is one of the toughest obstacles to overcome when you start cranking up the performance here.

More times than not, more damage can be done by babying your car (when under boost) then just giving it everything it has.

Aaron Miller

[turbovanman²]

+1... not every cylinder will be affected at the same time. Eventually there is a good possibilty. And the part throttle issue brought up was a good one...

He posted his part throttle air/fuel ratio's, they looked pretty good.

[glhs875]

With proper timing and air/fuel ratio 94 octane will support an 18 to 1 effective compression ratio with no problems. So unless the static compression was really high, with no more boost then he said he was running the octane level should be fine.

[8valves]

With proper timing and air/fuel ratio 94 octane will support an 18 to 1 effective compression ratio with no problems. So unless the static compression was really high, with no more boost then he said he was running the octane level should be fine.

According to compression alone though! Now heat on the other hand... part throttle mid boost level runs won't achieve that cylinder pressure limit, but it might have surpassed a safe heat level, espescially being at part throttle, which = part fuel. Ya see where I'm going with this? That's some bad wording by me, which I usually pride myself on better gramatics online.

Aaron Miller

[11secGLH]

The Chevron 94 we have here is very good fuel. I drag race a 68 dart that does low 10's (555HP on the dyno) and I've run it on 94 only for years and never had a problem. I ran 12.70's in this GLH in 92,93 on it at 18lbs boost, made 300 runs and drove 80,000 miles on that combo.You cant tell me it was the fuel. As soon as it went into boost I had 11.5 A/F.

[Dave]

Not to hijack, but why must you run more timing on a G-head??

[GLHSKEN]

Lower compression ratio

[turbovanman²]

The Chevron 94 we have here is very good fuel. I drag race a 68 dart that does low 10's (555HP on the dyno) and I've run it on 94 only for years and never had a problem. I ran 12.70's in this GLH in 92,93 on it at 18lbs boost, made 300 runs and drove 80,000 miles on that combo.You cant tell me it was the fuel. As soon as it went into boost I had 11.5 A/F.


Maybe but gas was a 1000 times better back in 92. Also, what combo did you have back then?



With proper timing and air/fuel ratio 94 octane will support an 18 to 1 effective compression ratio with no problems. So unless the static compression was really high, with no more boost then he said he was running the octane level should be fine.


Maybe but boost vs compression are 2 different animals, has been very well documented that each has its own needs. I have ran 18 psi on 94 and it pinged like a motherf@cker.

[glhs875]

Not to hijack, but why must you run more timing on a G-head??


Mainly due to the slower burn rate/flame travel of the fuel.

[glhs875]

Maybe but gas was a 1000 times better back in 92. Also, what combo did you have back then?





Maybe but boost vs compression are 2 different animals, has been very well documented that each has its own needs. I have ran 18 psi on 94 and it pinged like a motherf@cker.

With the right combo, much higher boost levels can be run on 93 or 94octane. I was successfully running 26psi on 93 octane in a daily driver on stock Mahles and with a stock cal. Was pretty much bullet proof. I can't remember how many runs I had on it, but it was alot. I didn't crack a piston until I tried going higher with the boost on 93 octane. Did fine with 28+ psi and race gas.

[glhs875]

Since it only took out one cylinder, I would suspect an injector or harness problem on that cylinder. Injectors have been known to flow test fine when cold, but then fizzle out when they get hot.

[glhs875]

According to compression alone though! Now heat on the other hand... part throttle mid boost level runs won't achieve that cylinder pressure limit, but it might have surpassed a safe heat level, espescially being at part throttle, which = part fuel. Ya see where I'm going with this? That's some bad wording by me, which I usually pride myself on better gramatics online.

Aaron Miller

I agree, and that falls in the proper tuning department.

[glhs875]

With the right combo, much higher boost levels can be run on 93 or 94octane. I was successfully running 26psi on 93 octane in a daily driver on stock Mahles and with a stock cal. Was pretty much bullet proof. I can't remember how many runs I had on it, but it was alot. I didn't crack a piston until I tried going higher with the boost on 93 octane. Did fine with 28+ psi and race gas.

I just wanted to add with proper tuning as well. And that combo was running low 8.20's @ 91 to 93mph on DOT's #2850 raceweight - 60's were in low 2.'s I also had to stage the boost lower in first gear to aid in traction. All I would do is drive it to the track, sometimes three hours away, pull to staging, clean off the tires(no burnout), stage while bringing the R's up to 2800rpm with about 5in. of vacum against the auto, then let her rip. I liked that combo so well that Iam building that same basic combo plus a little better breathing ability for my GLHS which is 500 to 600lbs lighter than my Daytona was. Should be interesting.

[cordes]

This is a really good thread with a ton of info in it. I think it really shows just how many factors there are that can add up and cause a failure.

It has brought up some interesting quetsions in my mind though, and in the end I am not sure we will be able to narrow it down to one item.

I still wonder what the advance is like on that S60 cal, and what the fueling is like at part throttle. Even if the A/F was at 11.6

[11secGLH]

There was a big change in Chevron gas when they went to unleaded, around 89 I think. Remember the red Chevron 94? Awesome stuff and admittedly the new stuff is not as good. But I've made over 1200 10.20 second runs in this car with Chevron 94 straight from the pump:
http://www.pix8.net/pro/pic/17716kNIl5/584996.jpg

As for my combo in 92, This is the car:
http://www.pix8.net/pro/pic/17716kNIl5/703628.jpg
http://www.pix8.net/pro/pic/17716kNIl5/703629.jpg
I ran a 85 T1 setup, lightweight rods even!!! It had the turbocity over the valvecover intercooler which I lengthened and mounted in front of the rad. I made a plate and welded a tube to it and mounted a 52mm throttle body on it. The tube got shoved in the hose in place of the draw thru 32mm unit. Electronics were handled by a MP intercooled logic. Had the same +1mm MP G head I have now with a MP cam. The only trick stuff I had was the 5th injector setup. A555, car was gutted, best run 12.76@108, best 60' of 1.70! I made 300 runs with this combo and it took alot of abuse on the street as well. I did try some higher boost and rattled it pretty good a few times. Usually took out the turbo first though. The one time I did break a piston I was doing about 125MPH for 5 mins (I used to be nuts, lol) and then I booted it. I figure from the sustained rpm the tops of the pistons got very hot and when I put the boost to it the tops of the pistons all blew into the pan.

[turbovanman²]

^^^^^Sweet, Mission raceway, I am going to try to be there lots this summer, :amen:


Yeah, that red Chevron 94 was good stuff, my dirtbikes loved it.:thumb:

[11secGLH]

I've been there every summer since they opened in 92 and I've rarely missed a weekend yet. I raced the omni in 92&93 and I started racing the dart in 94 and been there ever since. I sold my GLH in 95 to a young kid so I could buy a car trailer and I just bought it back off him last year. He didn't drive it much and it actually had the same tires on it! The plan was to build up the omni better than ever and use it for friday nite street legals.

[turbovanman²]

I've been there every summer since they opened in 92 and I've rarely missed a weekend yet. I raced the omni in 92&93 and I started racing the dart in 94 and been there ever since. I sold my GLH in 95 to a young kid so I could buy a car trailer and I just bought it back off him last year. He didn't drive it much and it actually had the same tires on it! The plan was to build up the omni better than ever and use it for friday nite street legals.

I haven't seen you out there the last 2 years so maybe this year, you'll be there and we can race heads up, I'm aiming for 12's :eyebrows:

[11secGLH]

I think I may have figured this out. The pistons that were installed by Chrysler reman were the cheapies, not even Mahle's. (was supposed to be a T2 long block but had a cast crank too) So after looking at the parts and checking everything over again and again, I've come to the conclusion it had a weak piston and saw just enough detonation in that one cylinder to cause a small crack the first nite I drove it. Then as I drove it more and it got the 10psi blasts, with all the fuel the +40's give, it had the fuel and the air (boost) leaking past the piston (because of the crack) to torch it out the way it did. Thats my story and Im stickin to it.Thanks for the help/replies, much appreciated. Chris.

[johnl]

GLHS875 - This part has me really confused -

"What I am getting at is with a G head that needs more timing advance than a swirl to work properly, the EGT's may have gotten to high due to not enough timing advance under boost, which could have led to a destructive process."

Why would EGTs go higher because the timing is too retarded?

My experience, admittedly NOT with turbos, says that the more advance the higher the EGT, and the more advance the more detonation.

Could we be dealing with pre-ignition in a fuel rich environment?

I don't know, I am too new to turbos and ignition/fuel maps that can turn conventional thinking upside down.

[turbovanman²]

I think I may have figured this out. The pistons that were installed by Chrysler reman were the cheapies, not even Mahle's. (was supposed to be a T2 long block but had a cast crank too) So after looking at the parts and checking everything over again and again, I've come to the conclusion it had a weak piston and saw just enough detonation in that one cylinder to cause a small crack the first nite I drove it. Then as I drove it more and it got the 10psi blasts, with all the fuel the +40's give, it had the fuel and the air (boost) leaking past the piston (because of the crack) to torch it out the way it did. Thats my story and Im stickin to it.Thanks for the help/replies, much appreciated. Chris.

Damn, I am getting good at guessing over the internet, :amen:

[8valves]

Glad you found your problem, sorry about the loss though. Both cars look damn cool. I need an old school Mopar, I just have to. Wheelstands are just a dream of mine! :D

Aaron Miller

[GLHNSLHT2]

yep the MP pistons are even Hypers. They just didn't rebuild them like they did in the initial cars. what'd hte plugs look like?

[GLHSKEN]

Glad you found your problem, sorry about the loss though. Both cars look damn cool. I need an old school Mopar, I just have to. Wheelstands are just a dream of mine! :D

Aaron Miller


Drive yours in reverse:thumb:

[87csx2.4]

With proper timing and air/fuel ratio 94 octane will support an 18 to 1 effective compression ratio with no problems. This is true to a point what I have found is that 93 octane is good to 10.5 effective comp.ratio at 35 degrees total timing and every pound of boost you go that takes you higher than that you either go 2 to 3 octane point per pound of boost or pull 2 degrees of timing per every pound of boost.When you get in the area of 13 or 14 degrees total timing you are pretty much done with pump gas in my opinion,unless you are injecting with alcohol.

[87csx2.4]

I still wonder what the advance is like on that S60 cal, and what the fueling is like at part throttle. Even if the A/F was at 11.6
If you run a s-60 cal with a swirl head and pump gas and cast pistons you're going to be doing a lot of rebuild work.The s-60 cal was designed for the bathtub head with a slower burn rate like brian said.The timing is way to aggressive for a fast burn head which doesnt need the timing because its more efficient.

[87csx2.4]

GLHS875 - This part has me really confused -

"What I am getting at is with a G head that needs more timing advance than a swirl to work properly, the EGT's may have gotten to high due to not enough timing advance under boost, which could have led to a destructive process."

Why would EGTs go higher because the timing is too retarded?

My experience, admittedly NOT with turbos, says that the more advance the higher the EGT, and the more advance the more detonation.

Could we be dealing with pre-ignition in a fuel rich environment?

I don't know, I am too new to turbos and ignition/fuel maps that can turn conventional thinking upside down.Some good questions here egt's will give a false reading if there is not enough advance to properly burn the mixture.This wil cause fuel to be burned in the exhaust manifold which gives the false high egt,it usually just burns the exhaust valves though.If you are on the rich side of optimum fuel tuning and egt's are high I have seen 150 degree temp drop with just 2 to 3 degrees advance.

[glhs875]

This is true to a point what I have found is that 93 octane is good to 10.5 effective comp.ratio at 35 degrees total timing and every pound of boost you go that takes you higher than that you either go 2 to 3 octane point per pound of boost or pull 2 degrees of timing per every pound of boost.When you get in the area of 13 or 14 degrees total timing you are pretty much done with pump gas in my opinion,unless you are injecting with alcohol.

I agree with you, but I was going by what the total advance is normally under boost with a stock 8V Chrysler cal, which ranges from 22 to 27 total degrees on the ones I have checked including the 12 deg base.. My 88 Daytona had only 10deg computer adv by 10 to 12 psi, and many different 86 cals I checked had 15 deg. computer advance by the same psi levels. I could actually go a little more than the 18 to 1 ratio on my Daytona with the 7.9 static compression and 22 deg total with 93 octane. I was running 26psi succesfully on 93 octane in that car. With my 87 GLHS and around 8.5 static compression along with the 27 deg total timing I started having problems with detonation around 18psi of boost on 93 octane. Having a programable computer alows a person to maybe go farther with a given octane level. That .6 less in compression and 5 deg less total timing made a huge difference in the amount of boost I could run.

[glhs875]

Some good questions here egt's will give a false reading if there is not enough advance to properly burn the mixture.This wil cause fuel to be burned in the exhaust manifold which gives the false high egt,it usually just burns the exhaust valves though.If you are on the rich side of optimum fuel tuning and egt's are high I have seen 150 degree temp drop with just 2 to 3 degrees advance.

Thanks, for your help Kevin!!:thumb:

[John B]

Wheelstands are just a dream of mine! :D

Aaron Miller Try reverse!:p How cool would THAT look!! (I'd angle the side mirrors down a bit first though...)

[cordes]

Try reverse!:p How cool would THAT look!! (I'd angle the side mirrors down a bit first though...)

Having seen the video of the rampage doing it, it looks hilarious.:thumb:

[omnivore]

Looked like a pinging to me too. I used to run a S60 cal, and to keep it together on the street on 94 octane, I had to run timing way back at 5 or 6 degrees. Anything more was like stones in a beer can.

[GLHNSLHT2]

The pistons aren't really that bad :) This is bad. http://pnw-sdac.org/gallery/view_album.php?set_albumName=album55

[turbovanman²]

The pistons aren't really that bad :) This is bad. http://pnw-sdac.org/gallery/view_album.php?set_albumName=album55


Ok, you win on that one, :thumb:

[87csx2.4]

No doubt! Out of all the years Ive ran these cars Ive never broke or melted a piston,ive ran lean knocked the crap out of them from to much timing etc.But then again Ive never ran cast pistons,it just doesnt seem to payoff if you have to keep pulling the head to change pistons out.And let me tell you I run my cars hard ask anyone who has rode with me,cast piston are an accident waiting to happen.

[turbovanman²]

No doubt! Out of all the years Ive ran these cars Ive never broke or melted a piston,ive ran lean knocked the crap out of them from to much timing etc.But then again Ive never ran cast pistons,it just doesnt seem to payoff if you have to keep pulling the head to change pistons out.And let me tell you I run my cars hard ask anyone who has rode with me,cast piston are an accident waiting to happen.

I agree but forged or not, wouldn't have helped THAT motor, :lol: :thumb:

[cordes]

I agree but forged or not, wouldn't have helped THAT motor, :lol: :thumb:

No kidding, that piston wouldn't even be a good ashtray.

[GLHNSLHT2]

That's a bone stock T1 motor that was in a J-yard.

[johnl]

Some good questions here egt's will give a false reading if there is not enough advance to properly burn the mixture.This wil cause fuel to be burned in the exhaust manifold which gives the false high egt,it usually just burns the exhaust valves though.If you are on the rich side of optimum fuel tuning and egt's are high I have seen 150 degree temp drop with just 2 to 3 degrees advance.

Good stuff. Loving turbo-mopar.com already.

Put it the memory bank - rich and retarded can yield dangerous EGT.

How far "on the rich side of optimum fuel tuning" are we talking about?
Will plugs show rich too?

[Putter]

Put it the memory bank - rich and retarded can yield dangerous...

Case in point:

http://www.trulybadfilms.com/blog/archives/chips%20w%20simmons.jpg

[johnl]

Good one Putter

[11secGLH]

Hi thanks for all the help/replies... I got some forged wiseco's and put another engine together with all the same stuff. I've been driving it for 3 days now and it runs pretty good.I have some questions about egt temps but I think I'll start another thread about that. Thanks again, Chris.

[8valves]

Hi thanks for all the help/replies... I got some forged wiseco's and put another engine together with all the same stuff. I've been driving it for 3 days now and it runs pretty good.I have some questions about egt temps but I think I'll start another thread about that. Thanks again, Chris.

Wow, that was quick work. Let us know how it works out for you, maybe you'll start to run down your other Mopar! :p

Aaron Miller

[turbovanman²]

Wow, that was quick work. Let us know how it works out for you, maybe you'll start to run down your other Mopar! :p

Aaron Miller


Not really, I am the same way, usually stay late after work and fix it. Have done headgaskets after work, replaced broken piston etc, :thumb:

[11secGLH]

Hi all, I was going to start a new post but I thought I would revive this one so its a little familiar to everyone. I've been driving the car for about 2 months now and it runs pretty good. One thing that I don't like is at 1/2 throttle, the thing just screams with 16 or 17 psi, but at WOT the power actually drops off a bit. I'm thinkin its the S60 cal, I just bought it to get me thru until my TU cal gets here, hopefully in the next week or so.The only other possibility is when I put this car together I couldn't find a 52mm T2 throttle body. So I used one from a 3.3L V6 (looks the same). But when I ordered the TPS for the turbo2, the TPS turned the wrong way to be able to mate up with the TB so I had to get a V6 TPS. Follow me? LOL... Has anybody noticed this before? Could that be causing my WOT problem? BTW the TPS shows smooth %values and voltage when I check it with the scanner. thanks for your time, Chris.

[turbovanman²]

Its your cal, I had the same problem with my stock cal, would go like stink at part thottle then at WOT, fall on its face. This also happened with my TU cal but it was for 2 reasons-too rich at WOT due to my small IC, I turned the fuel pressure down to help but replacing my small IC fixed both issues.

As for your TPS problem, yeah, you just need to use one from a 89 and up T1. I believe the older T2's have male terminals, the 89's have female terminals, or vice versa.

Coming out to Mission Frid night if its not raining, I have my trans done so I am soooooooo there, :thumb:

[11secGLH]

Thats what I'm saying, a turbo TPS won't work because it turns the opposite way. I guess the throttle blade opens the other direction(?).

[turbovanman²]

Thats what I'm saying, a turbo TPS won't work because it turns the opposite way. I guess the throttle blade opens the other direction(?).

No, a turbo TPS will work but your using a newer T/B so you must use 89 and up turbo TPS, :thumb:

[11secGLH]

ok that makes sense, thanks. If you're out at Mission swing by and say HI.

[turbovanman²]

ok that makes sense, thanks. If you're out at Mission swing by and say HI.

If your around Friday night and its not raining, come for a laugh and watch the van run, :thumb:

[Putter]

Get video for us this time.

[boost geek]

Count me in!:thumb:

[turbovanman²]

Count me in!:thumb:


Sweet, see you on the grass, same areaish, :thumb:

[11secGLH]

I'll be there with my dart for sure, doesn't look like my TU cal will be here by then for the Omni though.

[DodgeZ]

Hi great site here, I plan to be a regular. The car is an 85 GLH, just converted it to T2 (fresh chrysler reman long block) and 88 electronics. It has a ported +1mm G head, 1 piece intake I modified heavily, and a ported exhaust manifold. T2 Roller cam, TU S60 turbo, 3" swingvalve and exhaust, A555. For fuel I have the 255 pump, AFPR, +40's, 3 bar map, MP S60 computer (just until TU cals come up again). I have a cheap but good ebay intercooler, 2.5" piping and Turbonetics BOV. I also did the #4 coolant mod.

I have worked at Dodge dealerships since 1986, built literally thousands of engines so I know these cars and what they will and won't take pretty good. This wasn't it. It started and ran great, I had my Innovate LM1 and snap on scanner on it and everything looked good. My A/F was 13.5 at light throttle/cruise, 15.0 on decel and 11.5 part throttle, 10 psi. I was driving it pretty easy for about 30 miles and then gave it a few short light throttle 10psi shots. After about 6 of those it developed a miss which got worse real quick so I pulled it apart. This is what I found:
http://www.pix8.net/pro/pic/17716kNIl5/759810.jpg
http://www.pix8.net/pro/pic/17716kNIl5/759811.jpg
http://www.pix8.net/pro/pic/17716kNIl5/759812.jpg

To me, it doesn't look like detonation it is TORCHED like no fuel. So I send out the injectors to get tested and they are good (118cc!!!) If the computer didn't fire the injector, there would have been 2 cylinders with problems because of the batch fire setup. I tested all the injector wires and they are good.The only other thing I can think of is the G head doesnt like the timing of the S60 computer? I'm sure there was no vac leaks as it idled well with good vacuum.

There is metal transfer to the block so it is toast. Not the end of the world but I want to make sure this doesn't happen again. I bought Wiseco forged pistons for some extra insurance and an EGT guage. Any thoughts or suggestions are appreciated.

I cut the top and elbow off the intake and the front half of the runners were milled down an inch or so. The center between 2&3 was milled out and inverted. We welded a 3" tube across the top, capping one end flat and a 3" cast elbow on the other end, blending everything in first. Here are the pics:http://www.pix8.net/pro/pic/17716kNIl5/759818.jpg
http://www.pix8.net/pro/pic/17716kNIl5/759819.jpg
http://www.pix8.net/pro/pic/17716kNIl5/759821.jpg
http://www.pix8.net/pro/pic/17716kNIl5/759822.jpg

where did the pics go?

[11secGLH]

I am about ready for an update on this topic. Those pics are gone. I do have a pic of the second set I burned up but they were wiseco's. Different cylinder though and I'm fairly sure it was the S60 cal on pump gas that was causing the problem:
http://www.pix8.net/pro/pic/17716kNIl5/970880.jpg

Chris W at Turbo's Unleashed went above and beyond the call and persuded Wiseco to send me a replacement set of pistons! Thanks Chris!!! I had Chris coat them and they are in the car now. I did take some pics I will post when I get a chance.

I 've had alot of bad luck with this car in the last year. I put it together last week with the new pistons, I replaced the G head with a mildly ported swirl, and used a cometic to put it all together. I had the injectors checked and I went over every wire going to the computer and verified everything's doing what it should.

I decided to drive it real easy for a while, (not like me lol) and it ran the best it's ever run. Until you put your foot in it. Under boost it would go very rich and start bucking and banging thru the exhaust I carefully leaned it out, same thing. I replaced all my vacuum lines because they were old/unreliable. It was hard to diagnose because it would only do it on the road. It got worse and worse under load and eventually died and would not restart.

I got it back home and figured out that the intermediate shaft and oil pump were munched badly!

[turbovanman²]

Dude, your in the same club as me and Don, :(

[Chris W]

I Chris W at Turbo's Unleashed went above and beyond the call and persuded Wiseco to send me a replacement set of pistons! Thanks Chris!!! I had Chris coat them and they are in the car now. I did take some pics I will post when I get a chance.


Wiseco has always provided OUTSTANDING customer service to our customers even when there is a question about the cause of the failure. That's why it pays to support the TD vendor rather then going direct to the manufacturer. We Hope things turn out better for you this time around. :thumb:

Let us know how things turn out,

Chris-TU

[11secGLH]

Thanks again Chris, I don't give up too easy. You know in 1992/93 I ran this same car, I had cast pistons,crappy 2" muffler pipe for IC piping, no big injectors, no wideband, no fancy cals, a crappy Turbo City over-the-valve-cover intercooler, no 3" swingvalve/exhaust etc.

I made over 300 12 second passes and put 80,000 hard strteet miles on it and never had any problems.I sold the car to a young kid so I could concentrate on the racecar and he had it for 10 years. I bought it back in '05 (still had the same tires on it!) with the intention of having some street legal racing fun with it at the track.

Now I have all the fancy stuff and let me tell ya it hasn't been that fun as you can see in all of my posts. The attitudes of people at the track and on the road toward the car have sure changed. I used to sit in the lanes amongst a sea of open headered, slick tired racecars and people would wonder what I was doing there with this piece of ---- Omni. Until I kicked their asses...(sometimes) Now I go to the track and there's hundreds of Honda's and other sport compacts and I pretty much blend right in.

The other big difference then to now is the tires that are/were available. Used to run on road race tires, they were better than stock tires but still nowhere near as good as you can get now.