Why the double post? No need to ask us twice

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I've fitted an EA82 carby motor into one of my MY's, and an EJ20 turbo into another, so apart from EA82T wiring I think I can cover the rest.
First question, is the car fitted with a lift kit?
At the very least the chassis rails will need to be cut/shut or "reshaped" to clear the cam covers. This is more extensive on an EA82 than on an EJ motor as the EA82's are wider. In particular the passenger side rail will need to be widened from the timing cover all the way back to the distributor.
I'm not 100% but I beleive the stock output of an EA82T is in the region of 100kw, but there are variants with differing outputs (JDM higher maybe?).
The conversion would be possible into an MY, I wouldn't say it would be overly easy though. My EA82 carby swap was a bit of a challenge, and there was no fuel / cooling / wiring mods to be made! I'd say it would be a little easier than the EJ20 turbo swap, the radiator doesn't need modification and I can't see the wiring being as hard.
An overview of the tricky points:
-Chassis rail modification to clear cam covers
-Crossmember modification to clear up-pipe for turbo (or sourcing and swapping to an EA81T crossmember)
-Fuel system upgrade to EFI, all hoses replaced, return line fitted, high pressure pump and most likely a surge tank too
-Wiring in the ECU, fitting wiring to car
-Custom radiator hoses to suit new engine
-Exhaust fabrication to suit new downpipe and most likely larger diameter (1 3/4 is a little restrictive for the EA82T!)
There are a few other small things that slip my mind at the moment. You will need to turn the oil filler pipe around to clear the battery for instance.
You also need to consider what gearbox you're running, and from this what clutch (the bigger the better).
As for the differences between the EA81 and the EA82... well I'll try and describe this without sparking an argument here

The EA81 is a 1781cc pushrod flat four producing around 55kw in standard form. The timing gear is run on a chain and it normally has solid lifters. It has a single inlet port and a single exhaust port per head, not a huge amount of power upgrade potential but it is an extremely reliable beast that will literally drive into the ground.
The EA82 is also a 1781cc flat four however it's an OHC motor with varying outputs depending on the specific model. They have two timing belts, one for each head and usually have hydraulic lifters. The carby motors are really just an OHC EA81, the real differences are in the MPFI and the turbo motors. These motors have twin port heads and higher power outputs. The reliability of these motors is often a subject of debate, although its fair to say in many cases they are a tad less reliable than their pushrod siblings.
Apart from that I feel its all much of a much. They are both only EA motors after all :P