Originally Posted by bgoodsoil
Hey thanks for that! I'm learning a lot in this thread already.
I guess the question is this: where does that Siebenrock kit fall on this? Is it the 'expendable racer' '100 octane' piston or can we run US pump gas (93 octane is the good stuff) and still keep the longevity?
Anybody know if Siebenrock's pistons are coated? The cylinders are Nicasil. I guess Stagehand'll have to test this one out for us.
edit: from their site:
Here's your homework Stagehand: fill up on 87 and see if you hear a tink tink noise.
the pistons in the pictures at the top of the thread are coated, thats the black bits, just a friction reducer more than anything. but worthwhile. Friction is basically heat thats not making you faster.
If you hear the noise its to late tbh. Knock sensors on EFI engines are excellent at detecting knock which happens around 15Khz in most SI engines. They can hear it a lot better than any of us and react far quicker.
Knock can always usually be sorted out without the detrimental way of just pulling back timing. But to do so usually involves effort and money, thus its usually done by pulling back timing.