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Unfortunately my 7mge blew. I need a new motor and was planning just to swap in another 7mge but started reading that the 2jzge is more reliable/ overall better. Is the 2jzge swap into a 87 n/a much harder than swapping in another 7m? I'm not into turbos so don't bother telling me to get a gte. Also could I use the 7m harness on a 2jzge? Thanks for the help
 

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Unfortunately my 7mge blew. I need a new motor and was planning just to swap in another 7mge but started reading that the 2jzge is more reliable/ overall better. Is the 2jzge swap into a 87 n/a much harder than swapping in another 7m? I'm not into turbos so don't bother telling me to get a gte. Also could I use the 7m harness on a 2jzge? Thanks for the help
Yes, the 2JZ-GE is an overall better and more reliable engine.
Yes, a complete and properly executed 2JZ-GE will generally be 'better' (~20hp more, slightly better mpg, more reliable) than a 7M-GE in equivalent condition. Generally.

Yes, you can use the 7M-GE electronics on a 2JZ-GE but some changes needed to be made. Also, part of the reason why a 2JZ-GE is better is because of the 2JZ-GE's superior ECU and better wiring etc, and keeping the old 7M-GE wiring and ECU is introducing a pretty big wildcard into the 2JZ-GE's 'better'-ness.

And then the ultimate truth is that the newest Non VVTi 2JZ-GE is almost 20 years old and the newest 7M-GE is over 30 years old. They're old engines, and that means any given 'new' engine you find is a wildcard unless you go through the whole thing.

Having messed with these cars since the late 90's, what I would do in your position is rebuild the 7M-GE you have, or find another 7M-GE engine and rebuild that one to swap in.

Start by familiarizing yourself with the MK3 Supra TSRM aka 'Toyota Supra Repair Manual' MK3 TSRM On-Line

Tear it all down to the bare shortblock. New rings, new bearings, all that good stuff. If your crankshaft has bearing journal damage, try to source another crank, any clean 6M or 7M crank will work. Most earlier MK3's have 6M cranks in their 7M's anyway.
Get a new oil pump and a nice gasket set and of course a new timing belt kit. Have the cylinder head gone through and install new valve stem seals and new valve springs at the least, and do a valve job & lash reset if needed.
Have the block deck and cylinder head deck both machined to 40RA or smoother and use an MLS (Multi-Layer-Steel) headgasket and torque the headbolts to 75ft lbs in at least 6 passes. Make sure you have the aluminum timing cover bolted to the front of the block when the block gets decked for this process.
For a 7M-GE I'd go with a 1.0mm thickness for a headgasket. Any thicker and you'll just lose some of the higher compression the 7M-GE needs as an NA engine. Be generous as hell with assembly lube when reassembling everything.
New distributor cap and rotor, new wires, new spark plugs, filters, etc, the usual suspects.

The end result will be vastly better than rolling the dice with a junkyard 2JZ-GE.

Good luck.
 

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I agree with C Cowboy, if you have the rebuilding skills down to the machinists level. Lots of tolerances need to be taken into consideration for a reliable rebuild.
 

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To play devil's advocate for a moment... if I wanted to stay NA with a Supra, a 1UZ makes a mighty fine engine for a heavy car, but such a swap might not be the best candidate for a first dive into the waters of engine swaps / rebuilds.
 

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To play devil's advocate for a moment... if I wanted to stay NA with a Supra, a 1UZ makes a mighty fine engine for a heavy car, but such a swap might not be the best candidate for a first dive into the waters of engine swaps / rebuilds.
thats a bad idea.... i like the idea but thats a bad idea ..... thats just soo much awesonness
 

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thats a bad idea.... i like the idea but thats a bad idea ..... thats just soo much awesonness
A 1uz is such a fine engine for sooooo many applications. I'll reserve my right to change my opinion when I do the timing belt here in the next couple years, but I'm a big fan so far.

If I had the budget for needless tinkering I'd put one with ITB's and lightened internals into the Miata. ;)
 
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