I bought a new BW 9 bolt rear end built to handle 500+hp. I have no brakes on the setup right now. It has caliper mounting brackets and thats it. I have a few question as i want to built the rear brakes as strong as possible since they r all going to be new anyway.

What type of brakes r better in the rear portion of im gonna say a 90 IROC 9 bolt.(thats wht this rear end seems to be out of) I ve been told the 1LE brakes r good but are the ls1 better? or is there any style brakes that r even better then that. I know some brake styles have bigger rotors but i dont wanna change the caliper bracket unless its a must.

With the brake systems what kind of vehicle do they come stock? like 1LE brakes came out of what car and year model? I work at a parts store and can get cheap OEM style parts if I know what kind of car to buy them from. Ive also heard that the parking brake cable should be changed when doing this swap? and the Pvalve. should the valve be changed to match the year model calipers?

Im kinda new to this but im just basically looking for a grocery list of parts to order that will match up to my new rear end that would be best for braking and style.

Also, the motor in this car will be pushing 500hp easy so i was going to get new wheels for the rear while i was at it. I have weld prostars all around as it is. What size prostar would fit over the brake styles and still be thick enough to get traction? anyone got any good sizes?

Thanx

 

Brakes and wheel fitment:

https://www.thirdgen.org/forums/brak...l-fitment.html

The fronts do @ 80% of the braking so concentrate your efforts there and back them up with a decent set of rear brakes. Wheels will dictate brake size and use will determine which ones will be the best for you. Which backing plates are currently on the rear? The LS1s aren't a direct fit onto a 9 bolt so I'd look toward a set of '89-92 1LE style rear discs and with custom backing plates you can go up to a full 13" rotor with those calipers.

1LEs are a good factory style option but again, depending on your wheel choice you can go larger for the same money. I'm glad to help you out. Thanks!

Ed

 

Did the 1le brakes come off of the 90 irocs? and if i get these brakes will they fit inside some 15" weld wheels?

 

Just saw that the 15" wheels will probably work. now on the other hand what size wheels would i have to run to get some 315 tires on them? and how much back spacing?

 

1LE= '88-92 for 3rd generation. They will fit 15"s without issue. I would think you'd need a 17" wheel to run a 315 tire, that's damn big.

Ed

 

Ed, you know your stuff. Do you know of any cross drilled rotors that are available for an 87' 9 bolt rear?

 

An 87 would have standard Delco-Moraine iron calipers and 10.5" rotors; however, your rear could easily be upgraded to PBR's (or the so-called 1LE's, though all 89-92 rear disc cars were equipped with them). Here's a link for the cross-drilled rotors:

http://www.spohn.net/shop/1982-1992-...air-82-88.html

Here's another for the PBR upgrade:

https://www.thirdgen.org/forums/faq-...iscs-89-a.html

BTW, if you have backing plates that look like the ones in the above link, the PBR's will be simple bolt-on--but those backing plates didn't come on an 87.

JamesC

 

Thanks so much James. This is really helpful. What does PBR stand for? Does this refer to the iron to aluminum (1LE) conversion?
I would prefer to junk my iron calipers and 10.5 rotors and upgrade to the aluminum calipers and 11.5 rotors. I have some pictures of my backing plates, but i can't confirm if i have the same ones you have- based on your link. Let me see if i can post the pics.

 

Aussie company. The link is about converting standand calipers and rotors to 1LE calipers and rotors.

Here's the correct backing plate, which can be sourced from Ed, I think, for the conversion:

https://www.thirdgen.org/forums/atta...ar-bplate1.jpg

JamesC

 

Here's a pic of driver side rear brake. Can you tell me if have the same backing plate that you have?

I'll have to post it from home, can't do it from work.

 

here's a link to pics of my backing plate ( Page 2)
https://www.thirdgen.org/forums/brak...ear-c5-c6.html

 

Ed, do you have the backing plates i would need to retro fit the 9 bolt aluminum calipers to my 87 9 bolt rear (that were equipped with the iron calipers?)

 

Which post number?

JamesC

 

i think baer sells a rear brake kit for our cars.... not sure tho... i would think bout trying to get a newer model maybe like a vette rear disk setup or something... since the vette 13" front brakes are a popular swap now... just a thought. you have to worry more about the fronts since they do most of the braking... the rears... i would think the stockers with an adjustable proportioning valve would be adequate. i guess overkill is better tho.

also id love to hear how u got a 9bolt BW rear to be able to handle 500hp... since im assuming thats rear wheel hp.... even with 500 at the motor thats close to 400hp at the wheels... BW 9bolts cant be build up... no aftermarket posi's, axles, or anything and then your still limited to the weak 7.625" ring gear etc. stockers when brand new are rated at a tiny 297hp and something like 350ftlbs of tq.... since u can only put stock posi's in, stock axles are 28spline. only thing out there for them is the reinforcing preload diff cover lol. 10bolts can be built to handle 400rwhp but wont last very long. but thats due to aftermarket stronger posi, axles, etc.