Flex fuel sensor on 94 LT1 EE possible?

[Fastmax32168]

Tom, Thanks for the thought, but the car can be driven just fine right now. It is just not operation at optimum, and it obviously wouldn't be with a "compromise tune" designed to allow it to just "operate" on various mixes. The car drives fine on 93
octane I Just need to take about 5 degrees of timing out of it, and that costs quite a bit of power. I am sure it is still over the 400 RWHP mark, so in a 3000 lb package, its not boring. Going to a thicker head gasket would change the quench area for the worst, I am doubtful it would be enough, or do any good. It could easily change the detonation issue for the worse.

[Tom H]

Going to a thicker head gasket would change the quench area for the worst, I am doubtful it would be enough, or do any good. It could easily change the detonation issue for the worse.

I can't see how a thicker head gasket would change the quench area... volume yes but area? I guess the thinner the quench the higher the velocity/better mixing/more power.
Not sure I know enough to post on this thread, so I will watch with interest.

-Tom

[steveo]

The car drives fine on 93
octane I Just need to take about 5 degrees of timing out of it, and that costs quite a bit of power. I am sure it is still over the 400 RWHP mark, so in a 3000 lb package, its not boring. Going to a thicker head gasket would change the quench area for the worst, I am doubtful it would be enough, or do any good. It could easily change the detonation issue for the worse.

it actually sounds like a good tuning challenge to me. you might be surprised what you can achieve on 93 octane if you don't just approach the problem as just dropping 5 degrees of timing. there is a delicate balance between AFR and timing advance that you can play with to get a lot of power back, and spark is really complex, some running areas might not need much help at all. you might have a lot of fun with it.

I can't see how a thicker head gasket would change the quench area... volume yes but area?

you're confusing deck clearance with quench, that's all. lots of people mix those up because even a lot of machinists seem to use the wrong terms and it gets passed around.

[Tom H]

you're confusing deck clearance with quench, that's all. lots of people mix those up because even a lot of machinists seem to use the wrong terms and it gets passed around.

Could you expand your answer and clear this up for me?

Thanks,
-Tom

[In-Tech]

If I am incorrect of what steveo is talking about, please advise.

Basically quench is the distance from the flat parts of the head to the piston. Let's say your engine is assembled with the piston .010" down from the deck(deck clearance). If you use a standard .038" thick gasket, you will have .048" quench. Most hot rod people try for .035" - .040" quench. The desired quench can be done with deck machining or gasket thickness.

[Fastmax32168]

Tom, The quench area is the tight area between the flat portion of the piston and the flat portion of the combustion chamber. Its purpose is to squeeze all of the mixture into the combustion area, so you want it as tight as possible without making contact. If you put a thicker head gasket in, then that area becomes less efficient, holds more mixture, and becomes more prone to detonation.