I have read just about all there is to read about an LS1 conversion and I swear I am more confused than when I started. I currently have a 91 RS 5.0 with rear drums. I am looking to convert to 4-wheel LS1 disc brakes. "89 Iroc Z" has some posts/websites that have been a tremendous amount of help but I am still a bit confused...

FRONT:
From what I am reading, it seems that all I need is to grab some calipers of a 98-02 f-body and rotors from tirerack or wherever. But can use my pre-existing spindles and just modify them or should I take them off the donor car? I have the drawings for the brackets and am an engineer, we have a machine shop here at work so that will not be a problem. And what else am I going to need for the front swap?

REAR:
Think I know what I am doing here. Gona go with LT1 rears, much easire to find in the boneyard.

Thanks
Dave

 

fronts, you can modify what you have, but if the car is a DD, not a good idea. A spare set of spindles would be a good idea.

You need ot modify the spindle, cut off the stock caliper mount, drill and tap 2 of the dust shield holes, turn the stock rotor down into a hub that fits inside the ls1 rotor, install longer wheel studs. New bearings too while your at it.

Swap the prop valve for the brakes to a 1le unit, leave the booster alone. Maybe even swap the brake master for a ls1 unit too, its pretty much a bolt in deal.

 

It is my understanding, that the 93-97s, used the same PBR calipers, as the 89-92s. Meaning you'd want LS1 rears.

 

I just want to get rid of my rear drums. You may be right but I thought that the LT1 rears were equivalent to the 1LE rears, not the regular discs although I may be wrong. Theres a boneyard a couple miles from me that has about 15-20 fbodys there, mainlt LT1's, so Im just gona grab some parts off those

 

And for a spare set of spindles, am I better off with a 3rd gen set or LS1 set?

 

LS1 spindles won't bolt up to a 3rd gen, so that pretty much settles that option.

 

You're correct, the LT1 and the 1LE PBR calipers are virtually the same.

JamesC

 

I think I know just about everything I need to other than:

1) where should I get my prop valve (off of a thirdgen or LT1... recommend new or used...) since im going from drums to discs. I thought mounting it in the rear of the car wouldn't be a bad idea.

2) And exactly which type of parking brake lines should I get (can I get them new from an autoparts store or is it more complicated than that), I was under the assumption that the stock drum parking brake lines will not fit.

3) And should I bother grabbing a master cylinder off an LT1/LS1 or can my stock one be sufficient for now. (could always upgrade later)

Thanks
Dave

 

With the exception of the mounting question, which seems like a ton of work for no real benefit, you'll find the answers to all your questions in the following link:

https://www.thirdgen.org/forums/tran...-10-bolts.html

JamesC