Parts/upgrades, difference between 87-93, 86?

about the engine the 86 have a different cylinder heads, and have a flat top pistons, if you are going to change the heads you need to check very careful the valve piston clearence, about the suspension i think is the same the only diference is both stabilizer bars and the fron brakes disc are bigger in the 87-93 stangs, if you need and specification see the link below:

http://www.jason.fletcher.net/tech/specifications/specs2.htm

The differences in chasis are minor. Just about anything for an 87+ with also work on an 86.

The primary differences (aside form asthetics) are the brakes, struts, and piston/head arrangement in the motor.

Putting 87+ struts and brakes on an 86 is a weekend job. The brake upgrade kits that you see for 87+ will also fit an 86. You'll need to swap over to the 87+ style struts. The bolt spacing at the bottom of the strut is different, is all.

Body bolts on the 86 will be standard, 87-93 will be metric.

pretty much everything is the same, except everything on the 86 performs less.

Yeah that should not be a problem like you said if you change the all engine why you can´t install it in a 86 fox. that are wrong.

I think that what they are referring to with the motor is perhaps the lack of mass air for the crate motors. It only half makes sense though, considering 87 and 88 cars were SD as well. If you decide to run one of those crate motors, you will most certainly need to swap from speed density to mass air. None of the cams (save the E-cam under certain circumstances) are SD friendly.

Otherwise, those crate motors are a drop in fit. There are only subtle differences in the engine bay. None of which, are things that you would notice during an engine swap.

Side note: If you decide to convert to mass air, I've discovered that it's best to convert your SD harness rather than swap in a 16 year old+ mass air harness from another car. PARTICULARLY if your SD harness is in good shape. Strange things happen to old electrical harnesses when yo uremove them from one car and bend, twist, and pull them into another. The other option is buy a brand new harness from someone like Ford Fuel Injection. Just thought I'd toss that out there.