Are EA81 and EA82 flywheels the same, or relatively?

Some differences...

 

Bolt pattern is the same. You can change back and fourth (like to put a d/r 5 speed in an EA81 car).

 

Timing marks are in different places, and the EA81 flywheel is beveled on the front (in relation to the car) side, while the EA82 one is not.

 

I don't know how they compare as far as clutch/PP compatibility.

I think the ea82 flywheel uses larger bolts?

the bolt hole sizes are different, so if you are using an EA-81 motor with a 5spd D/R keep the EA-81 flywheel, but use the EA-82 pressure plate and clutch at least i'm pretty sure thats what i did.

 

 

EA-82 clutch, EA-81 flywheel and pressure plate, thats what i did.

an ea82 flywheel will bolt onto an ea81 motor, but to use an ea81 flywheel on an ea82 you will have to drill out the holes for the ea82's larger bolts

CCR was very much against using the EA-82 flywheel with the EA-81, because despite the fact that it bolt up, it can still move, if ever so slightly, which could at an inopportune clutch dump could shear your bolts.

CCR was very much against using the EA-82 flywheel with the EA-81, because despite the fact that it bolt up, it can still move, if ever so slightly, which could at an inopportune clutch dump could shear your bolts.

 

Those bolts shouldn't take any shear if they are done up correctly - they are supposed to provide a friction joint, where the bolts are only in tension.

I wouldn't be worried about that at all, just makes sure the mating faces are clean (not oily).