SKREMEN: It isnt a hi-jack. We have MORE in common then u actually think. As far as i can tell, id say u had the same problem as me.... i wonder who built both our heads?
PS. Ur damage is usually associated with a snapped timing belt or a jumped belt or keyway. But only because i know the history i think otherwise...
so the mech's at fault...did u go back to him?
weq,
after reading your entire posts, you mentioned piston to valve contact, but thats what I 1st thought after seeing them pics. notice how the pistons broke in the valve recesses only.
I suggest you have your head leak tested and I dont think thoes valves will seal as well as they once did,
from looking at the pics of the piston crowns and chamber in the head, there is no sign of lean mixtures or detonation.
Yeh everything is being checked and replaced if needed (i have a doner head). Thanks for the advice :)Quote:
Originally Posted by ECU-MAN
Re lean: Everyone keeps telling me it was knocking. I cant see it, i didnt hear it (always boosted with windows down cause of the heat) alot of ppl cant show me it, but everyone keeps saying it happened.. Like i said, i had a wideband on it the whole time, A/F was tuned to 10.9 in boost and it held strong throughout the rev range..
Cheers for taking the time to look :)
micheal: He was at fault in a sense, but the engineer said my case would be very weak. He does this for a living (professional witness) and said its not a 'compulsary' part of building and engine, its rather an optional extra which is worth while - in the sense of the law.
My big case would of been against the builder of the head. Alas due to the timeframes involved (the reason why i have told the entire story, it spans over a year) there is no way i could really prove that he was souly at fault.
Weq
how do you then explain the cylinders cracking?
Did you say you SHAVE your Cilinder HEAD??? by how many mm?
IF you say that is so called a "reputational" tuner or builder, i think, yea, reputational, Good in talking SxxT...bad luck dude...is either you fried the thing yourself, or they fried it for you...and i guess, you can't have any claim from them for sure. and surely, they would not be responsible for the thing, if they do, i think you're lucky..but i doubt that...
one more thing, go and get yourself a set of Darton's Dry sleeves, and changed the cilinder head if i were you...a shaved head will never be good...
What compression are you running at the moment? 10.2:1? 10:1? 9.5:1? 9.0:1?
IF you want a good builder, find someone that does over 50 Vtec turbo's..or really good in Vtec..does like over 100 mods internally on vtec. Reputation doesn't really count if they have only ONE CAR to promote their name, if you get what i mean.
Ive been in his car, seen it go nearly right thru the rev range, the a/f was always a nice and consistent figure.
Let me recommend some reading for you and your builders... here! If you we're running the CP 85mm pistons you should have bored to about 85.09mm-85.1154mm (.004”-.005” over). They aren't a perfect circle piston. See aluminum has a pattern. It expands more in one direction than the other, all metals do, just aluminum does it more. So you have to take that in to consideration. That's why the piston it out of round, once it heats up it comes to a perfect circle, or close to one. I don’t know if the builder took that in to consideration but thought I’d mention it. Once you deck the head and block you have to make sure you get the proper stroke and gasket. The rod, crank and piston makers don't know what you are decking to so they make it for a stock height, then you have to get the proper gasket thickness. Now factory deck height is high enough to deck it a few times to make it flat but if there was significant warpage or nicks you might only get one or two passes. The head also needs reliefs put in to the valve seats so they don’t hit. Make sure you got the right size valves, Crower does have over sized valves and it’s easy to order the wrong set, I have before.
I know who tuned the car and have absolute faith in his ability.
But at what PSI what this demonstation.Quote:
Originally Posted by LVNIT
I have an inclination it was overboosted. Weq trying to sell a stock radiator in the FS section.. it appears he's bought something more up to the task.
I am of the opinion it was also overboosted.
the fact that 3 different builders were used leads to:
block was decked
+
head was shaved
+
piston to valve was not checked in VTEC
pretty simple equation = likely hood of piston to valve contact very high
but i ask why this did not show up on the dyno/driving?
plus - was overheating from too tight piston to cyl. wall clearance?
very good point - wouldn't the pistons and valves have hit each other the FIRST time u hit vtec?Quote:
Originally Posted by tinkerbell
Time to ditch the d and swop in a b then turbo it!