1991 n/a. Engine internals are stock. Added an HKS air cleaner. Am about to add a high flow cat/ apexi N1 exhaust combo.

Is the increased flow going to cause my N/A to run lean? If so is an S-AFC the answer?

If I do go with an S-AFC, how difficult is it to install and tune?

Advice/opinions appreciated!

TIA,
Nick

 

You will not make an N/A run lean with just bolt ons. You can pretty much do whatever you want, short of a huge BP , or PP engine, and be fine with stock injectors. Also, an S-AFC doesnt really let you add more fuel than thestock fuel system can do by itself, it allows to to fine tune the delivery. With a N/A and a S-AFC, you get gains by leaning out the mixture, because it is programed to run fairly rich from the ECU.

 

Cool.
So would an S-AFC be a good perfomance upgrade? Is it difficult to install and tune?

 

Install is pretty stright forward. The "norm" gain on a lightly modded N/A is somewhere around 10RWHP from a proper S-AFC tune.