Hello, I just bought a 1989 firebird formula WS6 and it needs some new brakes badly.

I am not sure which rotors to get, the interior was stripped out of the car before I purchased it so I am not sure if its got the bigger brakes (No RPO sticker, the one in the car doesn't match the vin#).

it has front and rear disc brakes. I was told that it had a 3.45 posi rear end but I have not tried to varify that.

I just want to get some stock replacements, I am not looking to do a conversion yet.. but sometime next year maybe. I have to finish my 93 first.

I looked at Advanced Auto but they offer brakes with the J65 option and the 1LE option... for the same part number. Thank in advance.

Kevin

 

Are you just replacing the rotors, or the calipers and pads too?

If I were you I'd take off the rotors completely and take them to the nearest auto store-- I know Pep Boys can do it. They might be able to resurface the rotors for cheap, but if there's not enough meat on them (like the ones that came with my rear end, they were GONE!), one of the guys at the parts counter can match up the rotor size pretty easily. (Actually, you could just measure the rotor diameter with a ruler and ask for something with the same bolt pattern)

Good luck...

 

Or you could take this opportunity to slap on some nice HP rotors that are slotted and drilled:



More info HERE

Sure... you pay more for these rotors but they will last longer and will work a whole lot better than stock.

 

Thanks, the rotors are pretty much gone, so I will be replacing the rotors and pads, the calipers are still good from what I can tell.

Did that 1LE cars come only with the L98 motor, or did they also with the 305 TPI HO motor. And is the 1LE rotor size 12"?

Thanks for the link to summit, I think I will shy away from cross drilled rotors because they tend to crack with the cheaper rotors under extreme heat (or spirited driving) unless you get the high doller Porsche type or cyro'd rotors.

Atleast I have noticed this on all my friends 4th Gen's with cross drilled, and on my own 93 Z28 that I autocross. The slotted work great for me.

Just my .02

Thanks again guys.

Kevin

 

The following link shows pics of the bigger GM brakes, front and rear:

https://www.thirdgen.org/techbb2/sho...hreadid=246768

I doubt that your car has the bigger fronts, but could easily have the rears. 1LE cars were both 350 and 305's. The rotors are nearly 12 inches as opposed to the stock 10.5's. Note the rotor-size difference in the first pic of the link.

JamesC

 

Look better yes but last longer...no. Drilled rotors are MORE susceptible to heating and therefore cracking around the holes since there's LESS metal in drilled rotors.

Easy way to tell if you have the big brakes: If your front calipers are aluminum you have them. If not, you don't.


Ed

 

Thanks guys, this site is extremely helpful. I will check the calipers to see what there made of.

Got my fingers crossed..

Anybody know if the 1LE came only with the 350 L98 motor? I think thats the case. So most likely I got a plain jane WS6.

Fine car anyways.. but I love the LT1 so much better (maybe because I have almost 30k invested in that car)

I wish I still had my B4C camaro...

 

As I say above, 1LE's came both as 350's and 305's--As I recall, I read that on some site devoted to 1LE cars.

JamesC

 

Sorry didn't see that part in the thread. Next time I will look harder

 

Buy this one, it's a nice one:

https://www.thirdgen.org/classifieds...tgo?adid=56686

Ed

 

Great car, great price. I wish you luck in selling it.

But in my current sitution, I don't think there is much that would make me want to sell my 93 Z28 for the B4C (the reason I sold my first B4C)

Looks great tho, good luck!

Kevin

 

Not my car, BTW...I just thought it was a good deal for someone in the market for a good car. If I didn't have 2 already I'd consider it.

Ed

 

I respectfully disagree... but then again, it's a free country.

 

An 89 F-body with the stock level (not hi-po) 4 wheel disc brakes probably has the J65 package. That's 10.5" rotors front and rear. Since it's an 89, you probably have the PBR rear calipers.

You can get a good set of Raybestos Brute Stop rotors at your nearest Kragen/Checkers/Shucks. For pads, get the Brute Stops or Bendix Titaniums. Don't spend a wad on fancy high dollar drilled rotors, they don't do much for a street car other than look nice. Slotted is cool, but again, it's better to spend on a great set of pads.

Replace the flex hoses with a set of Earl's stainless steel braided, and put in a set of Earl's speed bleeders.

Then, flush and refill the whole system with something good like Valvoline Synpower brake fluid.

If you do all the above, you should have decent brakes. If they're still not getting it, check your vacuum booster.

 

"The sun rises in the west"
"I respectfully disagree".

You cant disagree with a fact.

Drilled rotors are more prone to cracking and excessive heating.

http://home.columbus.rr.com/trackbir...led_rotors.htm

Straight from StopTech's website...
DRILLED VS SLOTTED ROTORS

For many years most racing rotors were drilled. There were two reasons - the holes gave the "fireband" boundary layer of gasses and particulate matter someplace to go and the edges of the holes gave the pad a better "bite".


Unfortunately the drilled holes also reduced the thermal capacity of the discs and served as very effective "stress raisers" significantly decreasing disc life. Improvements in friction materials have pretty much made the drilled rotor a thing of the past in racing. Most racing rotors currently feature a series of tangential slots or channels that serve the same purpose without the attendant disadvantages.