you need to run at least 93 octane in that beast with all those mods,, you are way too lean by the looks of those pistons. throw in a little ethanol and its toast.... jet up on mains and raise the needles or your in for a bad ride!joehunt said:
OK I have some more info, I talk to the original owner and asked him to have a look at this forum to see what he thought. He said there is not any distortion on the top centre of the piston where lean burn is mostly noticed. He also told my to say that it has 140main 4000 to 5000ft when it blow and it has two layers of head gasket removed. And he rode the sled for 5 hours the week before I bought it, doubling his daughter.
bluerocket
New member
joehunt said:
further confirming the detonation diagnosis.....
Like I said though if the fuel was the cause would there not be sign on the other piston?bluerocket said:
joehunt said:
My 97 is set up similar to you - Bender pipes, porting, single layer head gasket, etc... and I run 140's at 8000+. 155's here at home in the flatlands. Based on this I'm thinking you might have been a touch lean at 5000'. I've never used SLP's and our porting is probably different, but ........
mopar1rules
Active member
140 mains sounds lean, even at your 5000ft altitude. also, that rod looks bent in the pic. did you use a hammer to pound out the wristpin? please be honest. my bud hammered his wristpin out on another friends viper, and bent the rod doing so.
Question what octance of gas where you using ? second they alway run great when they are going to blow that a sign. I still stand on why she blow up you had bad gas if you did not have 91 in the tank you had E gas which in turns will dry out the cycl. Also i would like to know what size jets are in there because it went lean ckeck out all seals & boots hope this helps.
I didn't pull it apart so don't know and the guy that did knows what he is doing so.mopar1rules said:
mopar1rules
Active member
joehunt said:
you should ask him, cause like i said it looks bent. you will have problems down the road if you put it back together and the rod is indeed bent. you don't want to have to tear it back apart and spend more $$$ now do you?
we are putting a new crank in anyway, but he said it was bent from the garbage in the top endmopar1rules said:
Devilin AblueDress!
New member
Heres my 2 cents. If setup on sled (jetting/needles) we set up even in the sweet spot by previous owner running premium. If the half tank of gas in sled was stale at all (promoting det) and then topping off with reg (promoting det) and then any lil air leak/piece of crud in center carb(promoting lean) or even if the fuel screw on center carb was in a lil more than the rest. There is so many variables that can add up to what happened. Or it is completely possible sled had ben ran out of oil which "hurt" engine and guy sold sled before it came unglued. Unfortunately we all can speculate on what happened, None of us on here (even you) know what sled ran like a month ago. There is no "smoking gun" as to what happened. All I can strongly advise is go through any thing you are reusing, ESPEICALLY carbs,boots. I would check with manufacturer as far as altitude/jetting needles.
That could be the case but I don't think that this guy sold it becuase he thought it was going to blow up, he has been way to helpfull for that.
joehunt said:
Could be you ride different then him and kept it at a throttle opening he didn't and since folks here seem to think you're close with jetting combined with unknown fuel, where are the needles... deto rattled and cracked a worn piston skirt?
How do the other pistons measure?
Just a guess, but then I didn't notice the rod until Mopar pointed it out either so what do I know.
Ain't redheads purdy??