Here is a little fyi on the motor, Cp 9:1 pistons, Benson 83mm block, Carrillo rods, dpr stage 5 head oversize valves. 1000cc injectors, fuel pressure at 40psi, walbro 255hp pump Full race T67 H.O. my manifold and all pipes..
Tuned on Neptune by suprdave on 110 octane gas.

YES the timing is conservative
YES the car was running low 11’s for afr’s

Both Suprdave and if you would like Hrtuning (JR from Neptune) can verify this…

All I want to know is what could have caused this since apparently the tuning didn’t do it.
If you look at the pistons they all cracked in the same spot, the sleeve in #1 is almost at 84mm now (from the original 83) and it’s pretty fucked. You can move pistons 1 and 3 around so I’m betting the skirts are gone as well.
Please give me your feedback so I can maybe figure out wtf happen to this thing.

This has really set me back bad; I just got the motor together and in the car last Friday and Sunday (yesterday) It took a **** on me... $, time, sleep is gone and so so is my passion to fix this car anymore…. I don’t have the urge or the drive to expletive with it anymore 5g’s in paperweight just doesn’t do it for me…..

All I’m asking for is your professional opinions on the pics I have provided below.

Thank you,
Regards,
Adi Radoncic






















Modified by Adi Radoncic at 8:33 PM 10/21/2005


Modified by Adi Radoncic at 6:41 AM 12/30/2005

 

man not cool to hear

looks like a little melting? Maybe an injector went a little lean on you, but at the same time the spark plugs look ok. How did it blow? On a pull or DD'ing it?

Also it's not too clear as to what blew. I see piston #1 did.....did #3 also go?

 

OOOOOUUUUCCCHHHHHHH!!!!!!!! damn, sorry dude.
looks like, too little fuel, too much heat. (****!!! grimacing in pain and sympathy)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by abnaasefmb &raquo;</TD></TR><TR><TD CLASS="quote">OOOOOUUUUCCCHHHHHHH!!!!!!!! damn, sorry dude.
looks like, too little fuel, too much heat. (****!!! grimacing in pain and sympathy)</TD></TR></TABLE>

Definitely sorry to hear about this. Glad I could at least show you the maps to clear up the idea that it might have been tuning related. Hopefully you can find what caused this and prevent it next time around.

 

i would check the O2 sensor! then maybe the fuel system.

 

That is a classic example of high cylinder pressure on stock sleeves with 2mm of precious wall thickness removed.

In other words, your sleeves deformed under high cylinder pressure permitting ring seal to be lost. The escapeing hot combustion gases slipping through the deformation in the bore caused this damage.

You will note that the burns all occur on the stress receiving side of the major thrust axis of the engine. This also happened to be the side which the poorly designed CP intake valve reliefs are in the piston. These things played against eachother.

If you post some useful pics of the plugs, I can fully confirm that this engine was tuned perfectly and failed from mechanical design reasons.

From the pics you have shown, this appears to have been a very well managed engine that was built to fail.

-Luke

PS, Next time you are considdering pistons, perticularly for a FI purpose, you may considder something designed with post 1950s face design incorporateing squish/quench pad usage. Perhaps something with a non-onesizefitsall valve relief wouldnt hurt either. I have seen some pretty poor piston designs, but those CP units are in a league of there own.

 

i dont know, but i see you got the credit card on the table ready for next build lol

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mchuang &raquo;</TD></TR><TR><TD CLASS="quote">i dont know, but i see you got the credit card on the table ready for next build lol</TD></TR></TABLE>

lol damn people dont miss a thing do they?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LFP &raquo;</TD></TR><TR><TD CLASS="quote">That is a classic example of high cylinder pressure on stock sleeves with 2mm of precious wall thickness removed.
.</TD></TR></TABLE>

reading owns you!

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Adi Raaa &raquo;</TD></TR><TR><TD CLASS="quote">Here is a little fyi on the motor, Cp 9:1 pistons, Benson 83mm block</TD></TR></TABLE>

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

PS, Next time you are considdering pistons, perticularly for a FI purpose, you may considder something designed with post 1950s face design incorporateing squish/quench pad usage. Perhaps something with a non-onesizefitsall valve relief wouldnt hurt either. I have seen some pretty poor piston designs, but those CP units are in a league of there own.</TD></TR></TABLE>

funny how most people have no issues with them at all..I run CP's that are 81.5mm and have never had a issue at all..if you look close at the pistons and plugs you will the plugs are missing the straps and with the way the piston is melted/cracked it was detonation that killed the engine! most likely got some shitty gas and thats the cause or some how the timing got advanced.

*edit*

after seeing this pic you can see spots of aluminum from the piston on the valve and camber..DETONATION!



can also see specs of aluminum on the melted plugs..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LFP &raquo;</TD></TR><TR><TD CLASS="quote">That is a classic example of high cylinder pressure on stock sleeves with 2mm of precious wall thickness removed.

In other words, your sleeves deformed under high cylinder pressure permitting ring seal to be lost. The escapeing hot combustion gases slipping through the deformation in the bore caused this damage.

You will note that the burns all occur on the stress receiving side of the major thrust axis of the engine. This also happened to be the side which the poorly designed CP intake valve reliefs are in the piston. These things played against eachother.

If you post some useful pics of the plugs, I can fully confirm that this engine was tuned perfectly and failed from mechanical design reasons.

From the pics you have shown, this appears to have been a very well managed engine that was built to fail.

-Luke

PS, Next time you are considdering pistons, perticularly for a FI purpose, you may considder something designed with post 1950s face design incorporateing squish/quench pad usage. Perhaps something with a non-onesizefitsall valve relief wouldnt hurt either. I have seen some pre
tty poor piston designs, but those CP units are in a league of there own.</TD></TR></TABLE>

umm definatelly benson sleved

 

that suck, a little of topic, i didnt know cps made 83mm pistons, they didnt have any listings on there site

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by adseguy &raquo;</TD></TR><TR><TD CLASS="quote">man not cool to hear

looks like a little melting? Maybe an injector went a little lean on you, but at the same time the spark plugs look ok. How did it blow? On a pull or DD'ing it?

Also it's not too clear as to what blew. I see piston #1 did.....did #3 also go?</TD></TR></TABLE>

All 4 pistons are cracked. This was at the track while doing a pull.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ninesecteg &raquo;</TD></TR><TR><TD CLASS="quote">i would check the O2 sensor! then maybe the fuel system.</TD></TR></TABLE>

The car was tuned on Daves Motec sensor that he had just priorly used on 3 other cars that ran fine, I also have a fjo in the car at all times that would have confirmed it.

 

Wow! Some interesting comments in here

If those plugs look good, I'd like to know what looks bad Perhaps down to the ceramic on the neck???

I got a chance to see the motor first hand. Does anyone else notice how each piston (from #4 --&gt; #1) get progressivly worse? Could this be due to lack of fuel volume in the rail? Since I guess, in my mind, as you move down the cyl bank row you'd deprive them of more and more fuel. Could it be a weak or overwhelmed pump, maybe a FPR that isnt rising 1:1 like it should (happens all the time) ... who knows.

Just trying to toss some ideas out on an expensive and mysterious problem.

 

bad gas + high boost?

 

Heres my CP destroyed from prolonged detonation.


Yours looks like it melted from over heating.

 

y do you guys keep saying the plugs look good?

looks to me like at least one of them has the groundstrap completely broken off.
yeah its tuff to tell cuz the pic sux.. but i think i can c it.

also it looks like a shitload of detonation went on in here..
i think(and this is just a guess) that you can't see much of that peppering effect
on the pistons mainly cuz they're forged not cast..


I think something must have happened to lean you out..
or ur ignition timing went to **** somehow?? though i'm not sure how that would happen..

hmm, i'm suprized ppl don't hook up warning buzzers to their widebands, or EGT sensors.. let you know to let off before stuff like this happens..
then you could trouble shoot before all ur pistons melt

 

I am very proud of CP Pistons. They have invented a piston that can melt spark plugs now.
No matter how, who or what tuned this motor, something failed in the tune-up.

 

A good example for everybody spending alot of money on your Honda engine.... This person was prepared and spent alot to build a bulletproof engine that should have lasted, even had a wb02 in the car at all times and look what happened. It was even tuned By a reputable tuner. Sometimes **** happens.

 

since it's obvious it ran extremley lean in all 4 cylinders im going to put the blaim on the fuel pump. kinda hard to belive that 4 injectors would go bad at the same time so the only other thing left would be the fuel supply to the injectors---&gt;fuel pump

 

if you know the a/f was good, and the map showed the timing conservative, then either the physical timing wasn't synced with the map timing, a fuel pump failed, or you got some bad gas. that is detonation, nothing else causes damage that looks like that. the melted ground straps should have been the first sign.

 

I feel your pain...mine blew 2weeks ago. I dont know if i want to fix my paperweight either.

 

What was the actual timing this motor was running at what boost when it exploded?

 

DAMN! that sucks. seems like detonation maybe you went lean. did you check the injectors to see if they are still good.

 

could even be that the gas was not actually what he thought it was.

I remember reading about some FD rx7guy filling up on what he THOUGHT was premium, only to have his motor melt that day.

turned out it was some shady little gas station and they were just pumping regular **** gas and trying to pass it off as premium!!!!

fawk, who knows..

as I said before, warning buzzer connected to ur wb02 or EGT sensor would be a lifesaver for a situation like this..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by non-VTEC &raquo;</TD></TR><TR><TD CLASS="quote">since it's obvious it ran extremley lean in all 4 cylinders im going to put the blaim on the fuel pump. kinda hard to belive that 4 injectors would go bad at the same time so the only other thing left would be the fuel supply to the injectors---&gt;fuel pump</TD></TR></TABLE>

The fuel pump is a possibility if it dropped pressure which could have happen..

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Jared &raquo;</TD></TR><TR><TD CLASS="quote">if you know the a/f was good, and the map showed the timing conservative, then either the physical timing wasn't synced with the map timing, a fuel pump failed, or you got some bad gas. that is detonation, nothing else causes damage that looks like that. the melted ground straps should have been the first sign.</TD></TR></TABLE>

The 110 oct was fresh and I had a full tank of it, i pulled the plugs before this pass and after the tuning and they looked fine.
It was after the blow up run when they were burnt up like that but its definitely detonation that killed it.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mase &raquo;</TD></TR><TR><TD CLASS="quote">What was the actual timing this motor was running at what boost when it exploded?</TD></TR></TABLE>

21deg at 23psi

I personally think this motor ran too hot and created very high pressures in the combustion chamber, thats why all the pistons cracked and all the plugs tips melted off.