OK...After reading through all the threads on 9 bolt to 1LE swaps, LS1 brake installs, etc, I couldn't find the answer I was looking for.

I've got a complete 89 GTA 9-bolt rear, and I want to put it under my 87 GTA. Will the brake lines be a perfect change? I'm betting they will, since they are the same rears, even the same gear ratios! So, I won't even hafta mess with my speedometer.

I just wanted to make sure the threads on the brake lines were the same.

Any master cylinders differences? Autozone.com is calling for different units. Is there really a difference? Can the 87 unit get by, until the 89 unit can be put in? I have the 89 unit also. I have thhe complete donor car, actually.

 

Should be a direct swap. The 89-92 rear disc cars call for a J50 (drum) master, but...

https://www.thirdgen.org/forums/susp...fferences.html

JamesC

 

Yeah, I read that too, but it talks about 82-84s, not 87s or 89s.

Any ideas on the fronts? Same size, correct?

 

Brake lines will be a direct fit but to be correct you do need to swap masters. Get one for an '90 on up, they're all the same in these years.

If you have the complete donor car, swap out the master and prop/combo valve as one assembly, then you'll be good to go.

Ed

 

Thanks Ed! I figured as much. I guess it'll just hafta wait until I can enlist help. The rear by itself would have been quite a stretch for my to bigin with, the master and prop would be impossible.

Oh well, no hurry anyways.

 

If you have time now, soak the hell out of all the threaded fittings in penetrant so they won't make you mad when you do get around to pulling the parts off.

Ed

 

Will do.

After the rear for free, it'll be time to LS1 brake the fronts.