Originally Posted by mdisav

I believe they have different rear end ratios. I know the 87 has a 2.65. The 86 probably 2.88. If you crawl under the car and look at the back of the differential you will find out. Sometimes you have to do some scrubbing. I also believe the 86 may not have had the trap oxidizer. I have known of some that never came with it but I am sure it is possible that some have.