I originally made a post back on 10/11/04 trying to figure what was going on with my setup-->

https://honda-tech.com/zerothread?id=1019952

Well, the good news is that the GT35E did go bad for some reason, and good ole' Arturbo sent it in for me. After about a week Precision got back to Art informing him that they were going to warranty the turbo and replace the wheel. They really didn't go into any details as too what happened to it, but did mention that there was some contamination found, but didn't state what. So, I should have a freshly built GT35E back within the next week and a half or so.

After finally getting the time to tearing down the block here is what we found-->
http://pg.photos.yahoo.com/ph/...iew=t (posted link incase pics don't work)







The top rings were trashed like we had suspected, but surprisingly found the pistons were damaged. What I was told was that since the turbo went bad it caused the motor to run **** rich. See my wastegate spring is a .7 bar spring therefore only allowing us to tune for 10lbs and higher. Since the turbo went, and I was only hitting 6-8lbs around 7000Rpm, there was an excessive amount of fuel being dumped since we were never able to tune for it. All the excess fuel caused my rings to wash, and the excess fuel burned off causing the motor to run hot thus melting the pistons.

The actual block made it's way to the machine shop late this afternoon, and we will know the official cause of damage by tomorrow.


Modified by Bulldogg83 at 11:48 PM 11/1/2004

 

OUCH!

looks to me like that thing detonated.

sorry to hear about your troubles...


good luck with the rebuild.

 

Damn, that blows. Sorry to here that. And trust me, know the feeling.

P.S.
What machine shop are using? I have one in mind, but it never hurts to check.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mase &raquo;</TD></TR><TR><TD CLASS="quote">OUCH!

looks to me like that thing detonated.

sorry to hear about your troubles...


good luck with the rebuild. </TD></TR></TABLE>

No signs of detonation on the walls, but I will know more tomorrow when I talk to the machinest after he has gotten the pistons out of the block and can look at everything.

 

from what ive been told the areas around the intake valve reliefs are usually prone to detonation.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18cx &raquo;</TD></TR><TR><TD CLASS="quote">Damn, that blows. Sorry to here that. And trust me, know the feeling.

P.S.
What machine shop are using? I have one in mind, but it never hurts to check. </TD></TR></TABLE>

Using Stoid's.....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Bulldogg83 &raquo;</TD></TR><TR><TD CLASS="quote">

What I was told was that since the turbo went bad it caused the motor to run **** rich. See my wastegate spring is a .7 bar spring therefore only allowing us to tune for 10lbs and higher. Since the turbo went, and I was only hitting 6-8lbs around 7000Rpm, there was an excessive amount of fuel being dumped since we were never able to tune for it. All the excess fuel caused my rings to wash, and the excess fuel burned off causing the motor to run hot thus melting the pistons. </TD></TR></TABLE>

Uh, whoever told you that, i wouldnt listen to them....

lean conditions cause things to melt. heat heat heat is bad..... rich mixtures absorb heat.

if it melted, it would look different than that.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mase &raquo;</TD></TR><TR><TD CLASS="quote">

Uh, whoever told you that, i wouldnt listen to them....

lean conditions cause things to melt. heat heat heat is bad..... rich mixtures absorb heat.

if it melted, it would look different than that. </TD></TR></TABLE>

So more fuel would cool the motor rather than heat it? What would cause, and I quote, "heat heat heat?"

 

yes, if you took a motor, say ran it at 12:1 afr, lets say it ran 700 degrees C of EGTs. if you dumped a lot of fuel, made it run 10:1 afr the egts might drop to 500. while it could foul plugs, even wash piston rings, you arent gonna melt anything.


heat is caused by lots of things. running too lean is the easiest that comes to mind, the extra fuel we use on FI cars is to help absorb the heat within the combustion process.


detonation destroys **** on the other hand. lemme try to find a picture of a melted piston....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mase &raquo;</TD></TR><TR><TD CLASS="quote">yes, if you took a motor, say ran it at 12:1 afr, lets say it ran 700 degrees C of EGTs. if you dumped a lot of fuel, made it run 10:1 afr the egts might drop to 500. while it could foul plugs, even wash piston rings, you arent gonna melt anything.


heat is caused by lots of things. running too lean is the easiest that comes to mind, the extra fuel we use on FI cars is to help absorb the heat within the combustion process.


detonation destroys **** on the other hand. lemme try to find a picture of a melted piston....</TD></TR></TABLE>

Now that you mention it my EGT's would only get to around 650 on my Greddy 52mm Boost Gauge under full throttle. Cruising EGT's were around 550-600. Does that help explain anything? Well I know the car wasn't lean because at idle AF was around 10.2-10.4:1. I believe the last time we dynoed it with the bad turbo AF was around 11:3-11.5:1.

 

just another reason to add to the probability that it detonated, if your sure it was running 11.5:1 in boost or richer.

a lot of times when pistons get too hot or melt, it will make piston to wall contact, and u said that it didnt do that.

maybe another experienced engine builder can chime in about it...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mase &raquo;</TD></TR><TR><TD CLASS="quote">just another reason to add to the probability that it detonated, if your sure it was running 11.5:1 in boost or richer.

a lot of times when pistons get too hot or melt, it will make piston to wall contact, and u said that it didnt do that.

maybe another experienced engine builder can chime in about it...</TD></TR></TABLE>

do you think the pics are clear enough to see the cylinder walls?


Modified by Bulldogg83 at 12:38 AM 11/2/2004

 

i thought boost fuel maps react to boost? so how could you be running .. 10 psi fuel set up when the cars only making 7 psi?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by project dc2 &raquo;</TD></TR><TR><TD CLASS="quote">i thought boost fuel maps react to boost? so how could you be running .. 10 psi fuel set up when the cars only making 7 psi? </TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by project dc2 &raquo;</TD></TR><TR><TD CLASS="quote">i thought boost fuel maps react to boost? so how could you be running .. 10 psi fuel set up when the cars only making 7 psi? </TD></TR></TABLE>

He basically tuned the car for 10lbs and was unable to tune the car for 7lbs...thus not sure what the AF is actually at aronud 7lbs. From what I have been told even if tuned for 10lbs the map should adjust itself accordingly for lower boost levels.


Modified by Bulldogg83 at 1:07 AM 11/2/2004

 

yeah running rich wouldn't cause anything to melt.

 

I am not sure why those valve relief's are so large on that 84mm piston. my wiseco 84mm's easily have 2 more mm's of piston material around the edge. If I were to speculate, i'd say the thin part of the piston created a hot spot that was prone to pre-ignition.

 

all my 81 mm pistons that have ate **** like that were in motors that went lean and detonated.maybe you got some bad gas.

 

yeah the valve relief areas are real weak, JE's are known for that.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by espanol &raquo;</TD></TR><TR><TD CLASS="quote">all my 81 mm pistons that have ate **** like that were in motors that went lean and detonated.maybe you got some bad gas.</TD></TR></TABLE>

well I know it didn't go lean, but bad gas could be a possibility.

 

dang man ...

 

even if you had a 10lbs spring the 7 lbs part of the map was tuned to 7psi

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vaporboy12 &raquo;</TD></TR><TR><TD CLASS="quote">even if you had a 10lbs spring the 7 lbs part of the map was tuned to 7psi</TD></TR></TABLE>

that's what I am starting to think. I downloader the Hondata ROM Editor Demo and have been playing around with the demo maps on there to get a better understanding of everything.

 

Damn bulldogg you just cant catch a break

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 92SleepyHB &raquo;</TD></TR><TR><TD CLASS="quote">Damn bulldogg you just cant catch a break </TD></TR></TABLE>

tell me about it