DiabloWS6

iTrader: (8)

i been doing some research and just wanted to make sure of what i have found i have a 1986 t/a i upgraded to a 89 t/a gta rear 9 bolt with pbr brakes and rotors i then upgreaded the front to the 1LE now i think i have to upgrade master cyilinder since my car originally came with 4 wheel disc i think i have to upgrade to the - 18014286 - Same as the J50 option drum brake equipped cars from 1984-up. If you have drum brakes, you have the right master cylinder! It is only us poor schmoes with 1982-1988 rear disk equipped cars that need a different master cylinder- if this is correct let me know i also have to upgrade to the Part#14089496 proportioning valve in order for this set up to work properly.....some info i got from WS6transam.org

JamesC

iTrader: (5)

I used the site's info in my 1LE upgrade many years ago and have linked members to it many times since. Recommended.

JamesC

DiabloWS6

iTrader: (8)

the only thing that makes me think is the master cylinder why would the rotor/drum be better than the disc/disc master cylinder one

JamesC

iTrader: (5)

I followed the directions and couldn't be happier. That said, I doubt there's a significant difference. Note what GM says about disc/drum and disc/disc masters:

https://www.thirdgen.org/forums/brak...-done-big.html

JamesC

DiabloWS6

iTrader: (8)

thanks for the link it seems that the j50 would be better than my j65 master cylinder and is the same thing as ws6transam.org says I'm not trying to question his knowledge just needed to know why

89Formula_350

Hey guys,

I'm looking at the 1LE kits on the Hawk's Third Gen website ...

http://www.hawksthirdgenparts.com/pr...e-Package.html

It says that spindle modifications are necessary. What does that mean exactly?? Other than that, is this a good kit for direct replacement of the stock brakes that are on my 89 Formula 350 Firebird? Does it include everything I need or do I need to buy some extras too??

JamesC

iTrader: (5)

Check the following for the modfication:

http://web.archive.org/web/200605221.../1LEbrake.html

Yes.

Yes, it includes what you need for the fronts.

JamesC

89Formula_350

I assume the first 'YES' is that it is a good kit. Is the second 'YES' saying it has everything I need or that I will need to buy extras??

OK I took a very quick look at the link and it said that some 89 and later models came with the 1LE brakes? Forgive my lack of knowledge, but how would I find out if my car (an 89 Formula 350) has those brakes? If it does, should I just head to an AutoZone and buy whatever worn out parkts need to be replaced??

JamesC

iTrader: (5)

Edit above.

Simply go take a peek. If the front rotors are 11.7" and the car has dual-piston alum calipers, you have the 1LE fronts (which is doubtful). If your car has rear discs, it'll be equipped with the so-called 1LE rears (which all J65 car had 89-92).

If you'd like a pic of both for the sake of comparison, check my vbGarage (shed-like icon under my name and next to my on-line status.

JamesC

89Formula_350

JamesC,

Thanks for that. My problem is that I am in the Army and stationed in Korea. But I come home in 3 weeks and will have to pull my car out of storage and drive to my next duty station. But I know that my brakes need to be done. I wanted to order the parts and have them waiting on me for when I get home. But I still need to figure out what I need. Can I get all of this stuff from an Autozone or do I need to do an online order??

DiabloWS6

iTrader: (8)

You can get most of those parts of your local auto parts store you need the part number for them wich I don't have but for me it was just easier to order as a complete set from hawksthirdgen or you can get them from sphoon, instead of buying here and there from local parts store

Eds87ZROC

Another quick question in regards to3rd Gens,,,i just bought a 87 IROC Z28 w/ 4w disk.How aside from what i read about rotor size would i know if my car came w/ 1LE system? is there a code on RPO Sheet in center console? thanks

JamesC

iTrader: (5)

Welcome to TGO, Eds.

No 1LE in 87. Your 4-wheel disc set-up no doubt has 10.5" rotors with iron Delco-Moraine calipers, front and rear (probably a 9-bolt). The 1LE set-up had larger rotors with alum, dual-piston front calipers and alum, single-piston rear calipers. Should you like to see pics, check my vbGarage (shedlike icon next to my online status). The RPO is 1LE.

JamesC

Eds87ZROC

Appreciate the reply James.helps alot w/ getting parts.Yeah I saw the pics of your car,,very sharp.Mine I'll b honest is very far from looking that good.I dragged it out of some guys yard after sitting for 4yrs.Needless to say,,its a project.But again thanks for info.

nortron

Why do you need to change the master cylinder from a 4-wheel disc setup to a disc/drum master cylinder when upgrading to 1LE front brakes?

sofakingdom

iTrader: (1)

Because the early Saggy rear disc brakes (82 - 88) had SUBSTANTIALLY different hydraulic characteristics than drums, whereas the PBR rears are very similar in that regard to drums, so much so in fact that in some years the factory didn't even bother with different MCs or PVs; so if you're getting rid of the crappy discs, you have to upgrade to drum parts.

Chuck84TA

Forget the 1LE it looks like the Baer brakes are being sold for almost the same price!!!

http://www.hawksthirdgenparts.com/pr...22-Rotors.html

nortron

Thanks Guys. Yes - I have an 1987 Formula 350 that also won't stop worth a crap. I can bottom out the brake pedal and still not lock up any wheels.
The sytem is in good shape and no air in the lines. Can't for the life of me understand why GM would produce a 'performance' car with obviously underpowered brakes. Had an 88 Beretta that had the same problem.

I will look into Bear and Wilwood big brake kits as I also noticed the prices are not much more than trying to find all the GM 1LE parts. I assume it would be best to upgrade the crappy rear iron calipers and rotors as well. I want to keep the original 16" wheels so I'm limited to 12" rotors max as I understand it.

Any thoughts and pointers from those that have upgraded an 87 (or similar) would be appreciated.

paul_huryk

Unfortunately GM did have the means to put better brakes on the f-bodies, but only did on the rears (4 wheel discs) in 1989. They ran the 10.5" fronts from 1982 to 1992 with the exception of the 1LE. GM did it for cost, plus the fact that state of the art brakes in 1987 were 13" with 4 pistons - on a Ferrari or Porsche...

The iron rear discs have been a problem for every f-body owner since 1982, so yes you should upgrade those to the 89+ rear discs.

As 16" tires to fit the f-body wheels are becoming more scarce every month, I would give the suggestion of spending the money now to go up to a 17" x 9.5" wheel and tire combo. You will be doing it in a few years anyway when the 16" tires are all gone anyway... Then you can go 13" fronts and not have any problem - Baer, Wilwood, LS1, C5, C6 will all fit under 17" wheels - the only ones that will fit under your 16" are the 1LE that I know of.

nortron

Paul,
Thanks for the input. For the front, I did find a Bear (11") brake kit and a Wilwood 12" brake kit that will fit in the 16" wheels according to the manufacturer. I also found 1LE kits from a couple 3rd party shops for not a lot less money than the Bear or Wilwood kits. I guess the advantage there is that the 1LE pads are very common. I don't know if the Bear or Wilwood pads are a special size or not.

As for the rear upgrade, the only kit I have found so far is a Bear (Claw?) kit with 12" rotors, calipers, mounting plates etc. What did you use for the rear brakes? thanks again. Ron

paul_huryk

A lot of the 12" kits work well, including the 1LE, but not too sure about the 11" ones - which are probably meant for 15" wheels.

Baer's 12" kit is a 13" kit with the rotor cut down to 12" for smaller wheels.

Baer and Wilwood pads are all readily available, sometimes they use the same pads as OEM calipers.

I upgraded my Camaro in 1997 with a Baer kit all the way around - C4HD is what they refer to it now as: 13" front rotors with 2 piston PBR calipers, 12" rear rotors with 1 piston PBR calipers (integrated parking brake). My GTA is an 89 so it has the PBR rear brakes from the factory and I have a 13" Wilwood FSL kit on the shelf for the front - will hopefully be installed soon. Keep in mind that I was running the 1992 Z28 wheels on my Camaro - the only 16" OEM wheels to fit the 13" Baer kit, GTA has our 17" wheels and they fit with a lot of room to spare.