A9L2 - FKARCH and FKARC1
Posted: 2026 May 19, 14:34
Setting up A9L2 from recent download.
When I changed SARCHG to 347, I noticed the comment said to update FKARCH and FKARC1.
FKARCH had 0.99
FKARC1 had 0.20
The comments had instructions to calculate using manifold volume. My intake is Edelbrock Victor Jr part #29215, which is a single plane carb intake with injector bungs welded at every port. I did searches and found manifold volume was 2.7 to 2.8 liters, but in newer strategies it said to use 3.5 liters because this intake behaves like a larger EFI intake.
Honestly I didn't understand what to feed into the equation in the comment. My engine ran quite well on the factory A9L tune. No stumbling or bogging on tip in. So I opened a stock A9L to see what these value are.
FKARCH - 0.2
FKARC1 - 0.25
I entered these values into my A9L2 bin as a starting point. Should I have left those values untouched? How do you properly tune these values?
When I changed SARCHG to 347, I noticed the comment said to update FKARCH and FKARC1.
FKARCH had 0.99
FKARC1 had 0.20
The comments had instructions to calculate using manifold volume. My intake is Edelbrock Victor Jr part #29215, which is a single plane carb intake with injector bungs welded at every port. I did searches and found manifold volume was 2.7 to 2.8 liters, but in newer strategies it said to use 3.5 liters because this intake behaves like a larger EFI intake.
Honestly I didn't understand what to feed into the equation in the comment. My engine ran quite well on the factory A9L tune. No stumbling or bogging on tip in. So I opened a stock A9L to see what these value are.
FKARCH - 0.2
FKARC1 - 0.25
I entered these values into my A9L2 bin as a starting point. Should I have left those values untouched? How do you properly tune these values?