im about to do a huge fuel system upgrade on both my rx7's

fc with 550 primary and 1600 secondary ms2 extra

fb with 550 primary and 750 secondary ms1 extra

im not 100% how to go about entering in the numbers to calculate for my injectors being so different from stock size. can anyone explain the math for doing this correctly? or do i need to do a staged map for the huge gap between the primarys and secondarys?

 

Assuming the FC is going from 550cc pri + 550cc sec to 550cc pri + 1600cc sec.

All you do on that car is change the size of the secondary injectors to 1600cc in the staging page. I would also suggest you stage based on duty being at 85% and then use 5% hysteresis.

If you stage in 1600cc injectors when the primaries alone reach 85% you'll still cut back all the way to a new duty cycle in the 20s or 30s of % duty.

 

On ms2/extra, I would suggest using the table-based staging feature. That'll give you the best staging behavior of all the options (so much so that I'm considering removing the other options for ms3).

Ken