Ive got the 2.2l motor in my shadow, ive got a 2.5l motor in the garage that Im getting ready to rebuild. Question is can I drop the 2.5l motor in my car without swaping the ecu? the blocks are the same, head/TB are the same only diff is the stroke of the pistons. I would assume that I dont need to swap the ECU out (plus I dont really want to find one to swap it with) Just gotta find out soon so I know what to do, the motor was planned to go into my 91 shadow which also had the 2.2 and never thought about this til now...the motor in my 93 is starting to knock worse (rod bearings) and the piston rings are about shot in it...New plan as of right now is going to be - drop the 2.5 in my 93, then rebuild the 2.2 and drop it in the 91 (2.5 has a bit nicer performance anyhow). Otherwise I will just drop the 2.5 in the 91, put insurance and plates on it, drive it while i rebuild the 2.2 and finish the bodywork/paint the car. So if anyone knows, or has done this please let me know what i need to change (if anything) to swap from a 2.2 to a 2.5

 

You will need to swap out the SBEC unit with the 2.5 SBEC. The 2.5 SBEC are calibrated for more fuel delivery and spark curve. I'm not saying the 2.2 SBEC won't work, but it won't work properly...

 

Whats a SBEC unit? lol *googles it*

 

The SBEC (ECU) unit is located on the left side inner fender, beside the battery.....Crono: 84-87-logic module and power modulle; 88-SMEC; 89-95-SBEC

1989-1995 (2.2 & 2.5)

New Common block 2.5- same rods & block as 2.2, larger crank snout

2.5 still equipped with balance shafts, unique crank and pistons

89 SMEC electronics and 4 wire O2, 90-up SBEC electronics and wiring

2.2 only used in Sundance/Shadow after 91

PFI Flex Fuel 2.5 1993-1995