Anyone else notice the 800 pound gorilla?
#16
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My bet is that there will be more HG failures if people continue to run their SCer with the stock ignition maps.
Originally Posted by ErnestSw
3 Engine designers have universally reduced the compression ratios in supercharged cars to deal with these facts.
Originally Posted by ErnestSw
4 Andrew's is the SECOND supercharged car to experience head gasket failure in the last year (the other one was in Australia). That's 2 out of 60 or 3.3%.
Originally Posted by ErnestSw
5 I said DISCUSS, not defend. Everything has its price, including supercharging. I'm NOT saying supercharging is bad, just that there are known and predictable risks and that ignoring them is stupid.
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Or it could just be a bad head gasket. Jim Page up here in Green Bay has a very large collection of worn out head gaskets that came out of stock (not even high mileage) 928's. They simply failed.
With the Shark Tuner, too much timing is no longer an issue.
Hell, most of the 60 supercharged sharks are pre-shark tuner anyway. They are running just fine. Rick Carter is tracking his supercharged 928, drove it from Ohio to Elkhart Lake and back. His clutch did fail, so I guess that's the fault of the supercharger to?
Tim Murphy's battery died last week on one of his cars. Was that due to the supercharger?
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Andrew,
was the kit marketed as a "preproduction prototype" with a discount? Were you warned that it would blow your head gasket unless it was Sharktuned? Was detonation measured in the test car?
Seems to me that your post confirms the proposition that your supercharger caused detonation and therefore your head gasket failure.
Speed Racer,
was the kit marketed as a "preproduction prototype" with a discount? Were you warned that it would blow your head gasket unless it was Sharktuned? Was detonation measured in the test car?
Seems to me that your post confirms the proposition that your supercharger caused detonation and therefore your head gasket failure.
Speed Racer,
No. The kit was not presented as a pre-production kit. However, I had recently put a smaller pulley on the SCer to increase my RWHP (boost is addictive). DR, to his credit, warned me that he had not tried this setup and that I was venturing into uncharted territory. However, I felt confident the motor could handle it given the number of people that are running much higher levels of boost on their stock cars. Guess I was wrong.
Again, the SCer did not cause the detonation per se. It was the fallacy that using the stock ignition map along with the stock knock sensors would provide a wide-enough safety margin. It did not. With the advent of the STer for the EZK, I was able to design a chip that brought it down to a reasonable safety level (in my opinion).
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"Again, the SCer did not cause the detonation per se."
Wouldn't it be more correct to say that it was your decision to ignore the detonation caused by the supercharger that caused the head gasket failure?
My point, by the way, is that you can't JUST "plug and play" a supercharger without some serious risk. It seems that those who already have them would be well advised to use a sharktuner.
BTW, Andrew and Gretch, it seems to me, are at both ends of the spectrum as far as frequency of getting into the boost is concerned.
Wouldn't it be more correct to say that it was your decision to ignore the detonation caused by the supercharger that caused the head gasket failure?
My point, by the way, is that you can't JUST "plug and play" a supercharger without some serious risk. It seems that those who already have them would be well advised to use a sharktuner.
BTW, Andrew and Gretch, it seems to me, are at both ends of the spectrum as far as frequency of getting into the boost is concerned.
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Originally Posted by Enzo
Detonation will kill a head gasket. Even N/A cars detonate.
On the dyno we (Murph, Z, etc..) have logged knock on a 100% stock 928's.
On the dyno we (Murph, Z, etc..) have logged knock on a 100% stock 928's.
I'm sorry, mis-information like this drive me nuts. Any car not properly tuned will blow stuff or melt parts.
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This is mis-information:
This is the explanation:
I also mentioned this:
This is the explanation:
Originally Posted by Enzo
Too much timing and / or running lean caused detonation. It's that simple. Hell, he could have a bad injector.
Or it could just be a bad head gasket. Jim Page up here in Green Bay has a very large collection of worn out head gaskets that came out of stock (not even high mileage) 928's.
Or it could just be a bad head gasket. Jim Page up here in Green Bay has a very large collection of worn out head gaskets that came out of stock (not even high mileage) 928's.