Alfa Romeo Forum - View Single Post

Pud237 · 13-05-2008

Originally Posted by ukoldschool

I take it your car has its standard ECU replaced with a MOTEC then? because the standard GTA ECU's fuel setting cannot be changed.

The spark timing can be retarded, so it sparks later, through a remap. (This gives higher M.E.P. per cylinder and more creates more torque at the crank.) This is what OA means by "mapped for 98 octane fuel". Normal 95 octane would detonate before the spark activated if the spark timing was retarded this much, this is why 98 octane is then required. Same case with my V6 running a Dastek Unichip.

13-05-2008	#43 (Post Link)
Pud237 AO Platinum Member Join Date: Apr 2006 Location: North Yorkshire Posts: 14,572 Member car: Alfa 156	Re: Rolling Road last night. Originally Posted by ukoldschool I take it your car has its standard ECU replaced with a MOTEC then? because the standard GTA ECU's fuel setting cannot be changed. The spark timing can be retarded, so it sparks later, through a remap. (This gives higher M.E.P. per cylinder and more creates more torque at the crank.) This is what OA means by "mapped for 98 octane fuel". Normal 95 octane would detonate before the spark activated if the spark timing was retarded this much, this is why 98 octane is then required. Same case with my V6 running a Dastek Unichip.