yea the flange is different,yo will need to weld an mr2 flange onto the celi exhaust...but all the other info we gave you is also valid,you can't just pull one engine out and put the other in,one has a power steering pump,alternator on opposite side,different intercooler setup,different wiring harness,different resistor pack,turbo or n/a fuel pump(5sfe to turbo),if you are talking about turbocharging the 5sfe i wouldn't recommend it because the compression is too high and you would only be able to run a few pounds of boost or risk blowing your motor with detonation,you would also need some way to tune the thing like emanage or a safc,more power = more fuel and air and you have to do these things to your engine deliberately,they don't just happen...i hope that answered your question