91 4afe to 93 7afe questions... Options

[Punisher]

Ok, bought a 93 corolla DX.. thought for sure it was a 4afe.. it's hard as hell to tell the difference between the 4afe and 7afe sometimes.. I guess I just have to take a peak at the ECU. The VIN says it's a 1.8L... however, checking the VIN both engines use an A as the 4th digit lol.

I got a 91 4afe for a 100 dollars.. was going to pick it up tomorrow.. 115K miles and a new timing belt.

So now my question is... I know I can use the 4AFE but what would I need to change on the motor to run the 4AFE with the 7AFE ecu/harness so this can be as quick and simple of a swap as possible?

The motor in the corolla has a hole in the block directly below the oil filter.. have no idea why.. didn't get to investigate yet. I stuck my fingers in though and I didn't feel a piston rod or anything strange.. lol.

The ever so small amount of power difference between the 2 motors doesn't bother me, this is more about economy and reliability than power.