Nissan 370Z Forum - View Single Post

SG4247 · 07-10-2018, 08:13 PM

Could be a couple of things....

I would look at,

Extra compression from reduced deck height, .020" larger bore diameter, milled heads and larger piston domes will cause detonation with low octane fuel. Prolly need 96-98 octane to be safe for regular driving. I would pump some 100 octane into it when it is nearly out, and then drive it, see what happens. Depends on your tune, as to how much timing the motor will tolerate without detonation. If the sensors see knock signal for very long, that will put the engine in limp mode!

Also,
Piston hitting the head, decking the block, coating the pistons etc... it happens. If the head gasket thickness wasnt increased to offset the other changed dimensions, then interference can happen. Seen it.

07-10-2018, 08:13 PM	#12 (permalink)
SG4247 Track Member Join Date: Oct 2016 Location: OKC Posts: 776 Drives: 2010 touring Rep Power: 7841	Could be a couple of things.... I would look at, Extra compression from reduced deck height, .020" larger bore diameter, milled heads and larger piston domes will cause detonation with low octane fuel. Prolly need 96-98 octane to be safe for regular driving. I would pump some 100 octane into it when it is nearly out, and then drive it, see what happens. Depends on your tune, as to how much timing the motor will tolerate without detonation. If the sensors see knock signal for very long, that will put the engine in limp mode! Also, Piston hitting the head, decking the block, coating the pistons etc... it happens. If the head gasket thickness wasnt increased to offset the other changed dimensions, then interference can happen. Seen it. Last edited by SG4247; 07-10-2018 at 08:19 PM.