need to change chip for headers with motronic?
 

I have a 1986 with 3.2 punched to 3.6 with motronic. It was remapped. I have SSI and would like to go to less restrictive exhaust with headers. Can motronic adjust to the change or will the chip need to be remapped? Thanks

Motronic with O2 sensor will adjust to part throttle but full throttle needs to be re-mapped.

Thanks, i figured that might be needed.

Definitely need a remap. Many years ago when I switched from SSI to George’s 1-5/8 headers on a 3.2 converted to 3.4, the custom mapping for the SSI caused a major flat spot in the torque curve on the dyno when bolting on the headers. Ran both back to back, big flat spot in the 3500-4800 range.

I have a 3.6 in my 89 with Fabspeed 1 5/8 headers , you are choking your engine with the SSI's which are basically suited for a 3.0 engine ...
Had Steve Wong come up with a custom chip for my application , happy so far !

how did you get to 3.6? bored and stroked? thought 3.5 was as big as one could go using a stock 3.2 crank?

I believe 3.7 is possible (102mm bore should do it I think with the 74.4 stroke of the 3.2 crank) as LN Engineering makes cylinders of an appropriate size. However, and I don't know the numbers and other specific data, but I suspect the meat left in the case between cylinders might be getting pretty small after machining for the cylinder bore, not to mention the stud clearance.