Has Anyone Lost His Engine to 8 PSI?
08-21-2006, 03:49 PM
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Has Anyone Lost His Engine to 8 PSI? From my research, I've found that 8 PSI seems to be considered a safe amount of boost for a stock bottom-end LS1. I'm curious, though, if anyone has ever lost an engine running 8 PSI with the proper supporting mods and a safe tune. If so, could you please provide details of what went wrong?
Thanks,
Josh
Thanks,
Josh
08-21-2006, 05:49 PM
#4
i lost an engine to 0 boost :/
look at it differently, look at airflow and effective compression, not pressure. while usually pressure does relate to airflow, it doens't do it necessairly. torque/cylinder pressures is what puts stress on parts. that depends on efficiency, and you'll find that to differ quite a bit on FI systems. not all 8psi was created equal so to speak. things like cams, intercoolers, well installed valvetrain can have huge influence on efficiency, thus how much stress the setup creates on the motor. I wouldn't do FI setup on a non-forged bottom end, unless it's like 5psi, intercooled, and you got heads with dropped compression.
look at it differently, look at airflow and effective compression, not pressure. while usually pressure does relate to airflow, it doens't do it necessairly. torque/cylinder pressures is what puts stress on parts. that depends on efficiency, and you'll find that to differ quite a bit on FI systems. not all 8psi was created equal so to speak. things like cams, intercoolers, well installed valvetrain can have huge influence on efficiency, thus how much stress the setup creates on the motor. I wouldn't do FI setup on a non-forged bottom end, unless it's like 5psi, intercooled, and you got heads with dropped compression.
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08-21-2006, 10:53 PM
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Strong on 10.5 psi for 2 years running....i'd say close to 16-20k miles.
It depends on who tuned it, and what other factors are involved, ie heads, cam, etc. Cylinder pressures (as mentioned before) play a large part in any motor, and more-so on a stock bottom end.
It depends on who tuned it, and what other factors are involved, ie heads, cam, etc. Cylinder pressures (as mentioned before) play a large part in any motor, and more-so on a stock bottom end.
08-21-2006, 11:39 PM
#12
BAscily.. you never know if your motor is going to go.
You dont know if you have a weak piston or not. Generly with a safe tune your safe (go figure). But you never know if one of those pistons is weak and cant take the extra cylinder pressures.
My motor is brand new (well 10k new). It is a stock LT1. So im taking a big gamble putting boost to it. But if it blows, im gunna pull the motor and give it back to the dealership and say i want a new one. LoL... (motor is warrented. hopefully they dont call me on my "boost" lol)
You dont know if you have a weak piston or not. Generly with a safe tune your safe (go figure). But you never know if one of those pistons is weak and cant take the extra cylinder pressures.
My motor is brand new (well 10k new). It is a stock LT1. So im taking a big gamble putting boost to it. But if it blows, im gunna pull the motor and give it back to the dealership and say i want a new one. LoL... (motor is warrented. hopefully they dont call me on my "boost" lol)
08-22-2006, 06:56 PM
#13
Originally Posted by bowtieman81
So what caused you guys to lose the engine? Fuel pressure drop, bad tune, too much timing?
I drove mine a good month real hard with no issues
But was running late to meet some friends fk arpund and stop at race track for gas and she went that night 
9 people file complaints against them but I guess is use at your own risk gas 
08-23-2006, 09:31 AM
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I've been running 7# on my stock Z06 with an STS kit. I tuned it on the safe side. The leanest it sees under boost is 11.5:1 As it approaches redline I have the a/f dip to just below 11.0:1. I'm hoping the extra fuel will keep things together longer. And no more than 14 degrees of timing at high RPM/WOT. I have no doubt I can squeeze more power out of it, but I don't feel it is worth the extra risk. It has been working flawlessly for 10 months.
However, I do realize it could grenade at any moment. You have to be prepared for that...
Tommy
However, I do realize it could grenade at any moment. You have to be prepared for that...
Tommy
08-23-2006, 11:28 AM
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lost mine to 10 lbs. I'm sure it was the tune. The guy that tuned the car is an azzclown.
Sux cause the car was running great too, running 11.2's on drag radials full weight shifting at only 6 grand.
I'm sure it was the tune. The guy that tuned the car is an azzclown. Sux cause the car was running great too, running 11.2's on drag radials full weight shifting at only 6 grand.
08-23-2006, 11:42 AM
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Originally Posted by TaTommyWS6
I've been running 7# on my stock Z06 with an STS kit. I tuned it on the safe side. The leanest it sees under boost is 11.5:1 As it approaches redline I have the a/f dip to just below 11.0:1. I'm hoping the extra fuel will keep things together longer. And no more than 14 degrees of timing at high RPM/WOT. I have no doubt I can squeeze more power out of it, but I don't feel it is worth the extra risk. It has been working flawlessly for 10 months.
However, I do realize it could grenade at any moment. You have to be prepared for that...
Tommy
However, I do realize it could grenade at any moment. You have to be prepared for that...
Tommy
)But I'm running strong this year on stock internals... might try to squeeze one more summer before taking the forged plunge
I have seen 12 psi hold up for quite some time on a procharged set-up, never really "blew" just started with a lot of blowby...
08-23-2006, 12:06 PM
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stock motor over here, 5psi rear mount turbo...still strong (even tho' its only been a couple weeks lol) but yea my AFR was set to around 11.2 all around so thats pretty safe to me, hope it holds FoReVeRRRRRRRR lol jk im getting some 6.0L heads soon just so i can sleep well at night lol
08-23-2006, 01:41 PM
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5 psi? Oh, you're fine. 
Word to the wise... People are selling their stock LS1 longblocks minus accessories for around $1k...
I know, I know... Most people say, "Oh, I can't wait to blow my motor so I can get a new one." Now, unless you're rebuilding your particular block or depending on your money situation, think about this: I have been treating my car nicely MOST of the time on 8 psi with a great tune and HAVE NOT blown anything. I've just sold my stock 30k mile motor and it will help ALOT with my 8.5 CR 346 H/C turbo LS1 expenses... Just something to think about for some of you.
Word to the wise... People are selling their stock LS1 longblocks minus accessories for around $1k...
I know, I know... Most people say, "Oh, I can't wait to blow my motor so I can get a new one." Now, unless you're rebuilding your particular block or depending on your money situation, think about this: I have been treating my car nicely MOST of the time on 8 psi with a great tune and HAVE NOT blown anything. I've just sold my stock 30k mile motor and it will help ALOT with my 8.5 CR 346 H/C turbo LS1 expenses... Just something to think about for some of you.
08-23-2006, 05:35 PM
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Originally Posted by bowtieman81
So what caused you guys to lose the engine? Fuel pressure drop, bad tune, too much timing?