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As the title says,Supercharger claims another motor :headshake: I just got around to dissasembling my original motor from my car that I was running the supercharger on for over 18,000 miles problem free,or so I THOUGHT :doh: My car was formerly equipped with a popular supercharger,which shall remain nameless, and a J&S safeguard. My car consistantly ran 375-389 whp on the average and ran [email protected] on this setup.The car was tuned to a near perfect 11.5 A/F ratio under boost and NEVER once displayed any signs of detonation. Thw Supercharger was removed and sold last August of 2004 and the car ran several thousand miles N/A and never made a sound. The car did smoke but nothing major, but I did notice on my last oil change I only got about 1qt of oil out of the car :doh:
So long story short,I take the motor apart finally after sitting in my garage for a year, and I come to find a piec of piston broken off and GONE..I mean no trace of it...Not melted to the piston,heads,valves..Nowhere to be found. :headshake: However that cylinder wall was not really that bad,just some minor scuffing a .20 overbore will fix.However two other cylinder walls have some fine cracks in them at the bottom of the cylinder wall near the crank shaft. This block needs to be sleeved..Just thought I would share my story with you guys.Ill post pics later my camera batteries died on me while I was photographing..
 

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yikes!! glad to hear it wasnt in use when you made the discoveries. any idea of what might have done it? weak stock internals? or something related that you didnt think about.?
mdzowner
 

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Discussion Starter · #3 ·
yikes!! glad to hear it wasnt in use when you made the discoveries. any idea of what might have done it? weak stock internals? or something related that you didnt think about.?
mdzowner
I think it was detonation..But it never dispayed any audible detonation at the time and ran perfect. I also had the J&S safeguard hooked up which is supposed to pull timing and if it detects knock it pulls more.Guess it doesnt work. :headshake:
 

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I wish the sc wasn't nameless. I suppose I can search and find what you were running before.. but...

I guess I'm not sure why the SC is at fualt and not the equip running it. If the A/f was good like you state, I suppose the timing was too advanced.\

Thanks for the post.
 

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Its starting to seem like stock internals + FI = kaboom. Makes sense. The VQ35DE was not designed for boost. If you want boost, you must redesign everything.
 

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Its starting to seem like stock internals + FI = kaboom. Makes sense. The VQ35DE was not designed for boost. If you want boost, you must redesign everything.
Yep. It sure doesn't help that it wasn't built for it. But ask yourself; what is it lacking?

If you are going to get lucky and get more than 20k miles; you are going to have to run very conservative timing and fat (11:1) on boost. If you keep the intake charge under control, than you should be able to have many happy stock internal boosting miles.

Things will only get better as time and experience grow. But, you can see the trend, and I've tried to educate others about boosting "only" 400whp on stock internals. I'd rather have the car to start in the morning, than chance it and have to rebuild within a few years. (very optimistic)

I'd have to say at this point, it's has to do with the tuning. It's not like the pistons care about what psi is getting crammed into the engine. But the heat that they are having to withstand. Heaven for bid they actually start to experience some detonation and crack themselves into oblivion. When this happens, we're quick to blame the engine.. or the turbo or supercharger kit. But in reality, they are doing the job asked of them.. Whether they last isn't really the fault of the parts, but rather the lack of real world tuning. Perhaps the dyno isn't the best place afterall. But it IS better than nothing at all.

So, again.. I'm sure in years to come, people will start managing the stock internals as they learn the ins and outs of tuning the VQ for power. Once this is accomplished.. I think we'll see a lot more happy stock blocks putting out 400whp. But for now, that's just too much to ask.

Is it the return-less system, or lack of beefy internals? Both? I guess time will tell. One thing is for certain. A built VQ seems to take power a little more seriously. I don't think this has much to do with the oem parts not liking boost.. rather than the new internals being able to withstand the rigors of a less than perfect tune.

Just my 2psi.

<flame suit enabled>


p.s. I wish more kits had oil cooler kits. One thing I like about the HKS SC kit is that is uses it's own oil supply. Doesn't mix with engine oil. Temps = cooler. Engine oil = happier.
 

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Weird, but I thought you had the APS tt kit on your car, not a SC. Or is that the MRC car?
 

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Even with a good tune, things can go wrong, and piston damage can occur. Maybe the car was running hotter than normal. I cant remember if DaKing ran the kit without timing retard for a while...maybe it occured during that period. The stock cast pistons have the tiniest of top ring lands...it doesnt take much to break them. :( It's all speculation, by even with a PERFECT tune...a motor can still break.
 

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you mean the ATI POSCHARGER
ayman...is that really you?

i thought you were all about a supercharger...and TT sucks...and the kinetix was god...and APS sucks....and jullian sucks....etc.

where did the real ayman go???

:lmfao:
 
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