Quote:
Originally Posted by danhr
agreed, but is the additional timing attributed to the cooling or the octane?
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I believe it's more from octane then cooling with Meth. The thing is with SBE cars running Meth is it cools the Air temp coming in to keep the ECU from pulling timing and the increased octane allows for a lot more timing, but the cylinder temps still get pretty high because there isn't the same level of cylinder cooling on combustion compared to spraying Ethanol through the injection system... and the rings will butt if you try to run the timing up to the point where you see some KR and pull it back a degree or 2. This is why I believe there is a lot of pump gas/meth failures on SBE cars.
I am no expert by a long shot and honestly not sure what is safe on a SBE car with Meth. Need to be able to log EGT's but nobody seems to go that far with them. The normal routine seems to be pull it apart and do rods/pistons/cam instead of seeing how far a SBE LT1 will go on boost. Be cool to see somebody like Brett really push one. Gap the rings, monitor EGT, cold Brisk plug, high octane fuel like C85, and moon boost. But gapping the rings kind of removes it from the SBE conversation.
I know Brett now tunes LT4's on meth to run a bit richer then he use too. And I think it's for the reasons I mention above. They won't live tuning them around .82-.84 because of the increased cylinder temps. On straight E it's no problem but add Meth and you need to get them down into the .77 range.
Either way Meth definitely works, it just needs to be used correctly. If I understood it more, I might give it a shot. But I have it in my mind I want to fuel my engine DI only for simplicity even though it costs a arm and a leg.