need to change chip for headers with motronic?

[pjh69911]

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

[brianlay]

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

[pjh69911]

Originally Posted by brianlay

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

Thanks, i figured that might be needed.

[175K911]

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.

[wildcat077]

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 !

[darrin]

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?

[Canada Kev]

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.