jess

Friends

Just purchased a 90 engine with 51k
miles on the clock. It is a TPI engine
as was the one in my 87 chassis.
Were there any subtle differences
between the two engines that I need
to be aware of. Thanks in advance.

PatternDayTrader

I can't think of any but I'm not an expert on those model years. That being said, if it were me I would just verify that all the sensors will connect properly to the harness in the car and I would verify the belt driven accessories all bolt up properly. Once that is all done I would install it and hope that it runs the way it should.

pologreen1

late 86-91 were almost the same. Very minor internal differences.

c4cruiser

The 90 used a different A/C compressor but you should be able to use the mounting bracket and bolts from the '87. The water pumps are the same. Distributors should interchange too. Check the fuel line attaching points, you may have to keep the '87 fuel rails.

The 90 engine used a smaller Hitachi-style starter but the '87 wiring should attach with no problems.

It would be a good time to replace the knock sensors in the block and the O2 sensor in the exhaust pipe.

The '87 had a cold start injector and I don't believe it was used on the 90. It may be a good idea to simply keep the '87 intake manifold and the runners and put on the later engine. That way everything on that '87 manifold will connect to the car such as. EGR, vacuum lines, injectors, fuel lines, rails, FP regulator, etc. I would check with local machine shops to see what it would cost to do port-matching on the intake runners.

WVZR-1

I would think that an ECU/ECM change would be considered timely and most valuable in the install. It's quite well documented for a modified upgrade, you're only adding the "engine" it was engineered to control. It would require some reads. If the rest of the chassis is "local" there would be much you could use from the shell I'd think.

I doubt the '90 "clock" displayed miles, you could assume it's maybe 26+ years old but miles?

KYC4

The '87 has a MAF system whereas the '90 will be a Speed Density system. So make sure that you use the proper ECM and other related hardware and sensors. Otherwise the rest has been covered in depth.

Later,

Lee

pologreen1

You need to describe more of what you have. I assumed you only needed the engine itself put in and everything else is there.

Don't go changing anything if you have it there. again 86-81 are the same. Roller style cam and aluminumm heads, and small internal things that don't matter.

All of your parts will go on the '90 block just fine.