New to brake line work, did a search and want to make sure i have the correct info on this. I have an 87 trans am with drums and am currently doing the ls1 rear disc swap. Are the ls1 caliper flex hoses fittings different from third gens? what are they called? SAE? what type of flare do they use? tubing size? I plan on getting new 3rd gen hardlines from t block to flex hose then modifying the part going into the flex hose. Does this sound like the best option?

Thanks for input
KeithO

 

your just swapping the brakes on, or the whole rear?

if just the brakes, the threads for the flex hose connections are the same. The drum brake hardlines are going to be too long. the need to be either cut and re-flared, metric bubble flare, or creatively re-bent to shorten them.

I did the same swap and i bent tight loops in the brake lines to shorten then enough work with the flex lines. My hardlines were new though, the old lines may be brittle and break.

New lines can be had from Finelines if you need them. And now is a good time to swap out the rubber flex hoses for stainless flex lines, i recommend earls.

 

LS1 hard lines have different flares at the T-block but are the same at the flex line connections. You can reflare your drum lines or just use a set of 3rd gen lines and you'll be fine. LS1 use inverted flare at the T and bubble flares at the flex lines. Each should be a 10mm line nut on a 4mm or so brake line. I'd just use the new lines from Fine Lines, I use them all the time.

Ed

 

well I am glad I posted, the rear is 3rd gen being modified for ls1 brakes. I will just get some 3rdgen prebent and be done with it.

Thanks!