Is the HF ecu the same as an SI? If not, what is the difference between the two?

 

Its an MPFI Ecu... but I believe it is programmed for fuel mileage and stuff as to where the S is more for performance... but you can always use it as a temp. if your Si ECU dies.

 

whats the difference performance wise?

 

Well. there is a 5500 RPM fuel cutoff, and the fuel maps are for a small 8 valve motor with a tiny IM, and throtle bodie. Plus it will be loking for an EGR valve. You could use it, but I think it will throw a code.

 

so for a MPFI swap I should go with the Si ecu huh? What other ecus can I use?

 

OBD-O Integra (will run really rich, and if you do do this you'd want 88-89)

 

so then I should just get a Si ecu?

 

get a 90-91 Si ECU. It has the best fuel maps. Sould go for anywhere between 50-100 bux. I think I PMed you about 2 weeks ago about trading some of your audio equipment for my 89 Si ecu, once i get my OBD1 swap done. But you are gonna probobly want a 90-91.

 

not a problem. I'd love to do the trade but I need this stuff ASAP.