90 GSX compared to 91-94 GSX:Pro's/Con's?

[TwoLiterV8Eater]

My FWD '90 ran 14.9@94mph bone stock. So I would have to say, No, the 90s are not slower than the 91-94's. The only bad thing about the 90's that I have seen is that they are a bit harder to tune than a 91-94. I swapped out my shifter with a Mofugus one meant for a GVR4. Works great and the throw is greatly reduced.

 

[boost_junky2000]

I have a 90, and i love it. One problem i have noticed is the damn ISC MOTOR. 90's are different then all other years and need an isc from a 90.

 

[neuralracing]

What is an ISC motor and what is the 4 bolt rear that everyone is referring to? ...... Differential?

 

[Cirus_93TSI]

90 cars have a weaker trans and i believe a milder cam, 90-91 cars have a 6 bolt engine and a 3 bolt rear, 92-94 cars have a 7 bolt motor and a 4 bolt rear
3 bolt rear ends are weaker, a 4 bolt is stronger and wolnt break or seperate on u as easily, switching from a 3 bolt to a 4 bolt rear is a popular upgrade for any car with a weak 3 bolt
as for an early 92 with a 6 bolt/4 bolt combo, good luck finding one, u will be looking and waiting for a long time, there are very few of these cars out there, and anyone who knows what they have isnt going to sell it, there are probally more running gvr4s out there then running early 92s with a stock 6 bolt/4bolt

 

[AndrewD5418]

90 cars have a weaker trans and i believe a milder cam, 90-91 cars have a 6 bolt engine and a 3 bolt rear, 92-94 cars have a 7 bolt motor and a 4 bolt rear
3 bolt rear ends are weaker, a 4 bolt is stronger and wolnt break or seperate on u as easily, switching from a 3 bolt to a 4 bolt rear is a popular upgrade for any car with a weak 3 bolt
as for an early 92 with a 6 bolt/4 bolt combo, good luck finding one, u will be looking and waiting for a long time, there are very few of these cars out there, and anyone who knows what they have isnt going to sell it, there are probally more running gvr4s out there then running early 92s with a stock 6 bolt/4bolt

What really makes it considerably weaker is it not being LSD. I'd bet any money you'd break a non LSD 4 bolt quicker than a LSD 3 bolt.
I'd go for a 90 and upgrade whatever you want to from a 91+. When the trans breaks, get a 91 trans, shifter linkage, and shifter base/assembly. I would ditch the 90 sensors right away though and go to a 91 CAS, Fuel Rail, ISC, ThrottleBody, etc... But that's just me.