How to destroy lq9 (pics 56 k NO)
01-14-2007 | 07:19 PM
#11
Based on the pictures it seems like a rod failure. On whats left of the piston for the pictures it doesnt appear to have any spots where it was burned through. Also the locations that the block and cyl. wall were damaged points twards a rod as well. IMO.
01-14-2007 | 07:22 PM
#12
Cant tell **** cause that pistons FUBAR
If you have bad detonation it can break a rod and cause the carnage that you experienced. Detonation is basically pre-ignition of the air/fuel mixture where the cylinder combusts before the piston is at TDC thus the piston is coming up in the cylinder and the combustion gases are trying to make it go back down in the cylinder but all 7 other cylinders are pushing the single piston to TDC causing HUGE amounts of stress on that particular rod/piston, not uncommon to flatten a rod bearing in high hp apps. If I had to guess you had some bad detonation when it popped. A few months back a guy on tech popped a motor just like you did and he had a log showing a huge amount of KR.
If you have bad detonation it can break a rod and cause the carnage that you experienced. Detonation is basically pre-ignition of the air/fuel mixture where the cylinder combusts before the piston is at TDC thus the piston is coming up in the cylinder and the combustion gases are trying to make it go back down in the cylinder but all 7 other cylinders are pushing the single piston to TDC causing HUGE amounts of stress on that particular rod/piston, not uncommon to flatten a rod bearing in high hp apps. If I had to guess you had some bad detonation when it popped. A few months back a guy on tech popped a motor just like you did and he had a log showing a huge amount of KR.
01-14-2007 | 08:12 PM
#13
That sucks. Time for a whole new engine I guess, this one will make a cool table stand or something now.
Weren't you having some tuning issues about a month ago and were planning on getting back to the track ASAP? Is this the trip back to the track since posting about those issues?
Weren't you having some tuning issues about a month ago and were planning on getting back to the track ASAP? Is this the trip back to the track since posting about those issues?
01-14-2007 | 08:41 PM
#18
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From: southern california
Originally Posted by 1slow01Z71
Cant tell **** cause that pistons FUBAR
If you have bad detonation it can break a rod and cause the carnage that you experienced. Detonation is basically pre-ignition of the air/fuel mixture where the cylinder combusts before the piston is at TDC thus the piston is coming up in the cylinder and the combustion gases are trying to make it go back down in the cylinder but all 7 other cylinders are pushing the single piston to TDC causing HUGE amounts of stress on that particular rod/piston, not uncommon to flatten a rod bearing in high hp apps. If I had to guess you had some bad detonation when it popped. A few months back a guy on tech popped a motor just like you did and he had a log showing a huge amount of KR.
If you have bad detonation it can break a rod and cause the carnage that you experienced. Detonation is basically pre-ignition of the air/fuel mixture where the cylinder combusts before the piston is at TDC thus the piston is coming up in the cylinder and the combustion gases are trying to make it go back down in the cylinder but all 7 other cylinders are pushing the single piston to TDC causing HUGE amounts of stress on that particular rod/piston, not uncommon to flatten a rod bearing in high hp apps. If I had to guess you had some bad detonation when it popped. A few months back a guy on tech popped a motor just like you did and he had a log showing a huge amount of KR.
well i know we were tunign the spark table when this happened. we added something like 5 degrees of timing. but it was at lower rpms and this happened at 5000 rpms with 17 degrees of timing.boost was about 10 psi at the time it happened. was on a 1st gear launch. we have the log when it happened and it didnt show any kr what so ever.
01-14-2007 | 08:49 PM
#20
Originally Posted by 02Reaper
wow. looks like the engine was pretty clean though. what kind of oil did you use, and what type of gas did you run?
2004- Im by no means a tuning expert, you may want to post a thread in the tuning section about this. I know enough to screw some **** up really good.