I understand you need to have the hubs cut off the rotors for the fronts but can I use the hubs off the rear rotors?

The Grand Am brakes are "plug-n-play" on the rear of the '84-87 Fiero. You simply remove the Fiero calipers and rotors, and bolt on the G/A ones. It's really that easy... well, aside from removing the now useless parking brake hardware.

So how does this compair to the Le Baron brake upgrade, or is it the same?

Thanks for the info on the rear swap, but I have had it done for about 3 years now. I am about to do the fronts and just want to know if I can use the hubs off of the rear rotors because I understand that the hubs need to be machined off the rotor. So can I use the hubs off the rears for the front GA brakes?

Why would you want to remove the parking brake? Isn't there another way to do this with removing it? For those of us in places where we need to have the parking brake to pass inspection.

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I gots the baddest Fiero on BRICKS!

quote Originally posted by AquaHusky: Why would you want to remove the parking brake? Isn't there another way to do this with removing it? For those of us in places where we need to have the parking brake to pass inspection.

No you don't have to remove the emergency brake,just wire it to the chassie or coil spring.You will be useing 4 FRONT calipers,2 in the front and 2 in the rear.There is now nothing for the emergency brake to attach to.Because of your inspection you can can probubly only do the front.But it allso depends on how through the break inspection is,it would probubly pass a visual inspection.

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goatnipples2002
As far as I know,if you plan on useing the rear rotars up front for the hub,(but not for the Fiero rotars as Grand am rotars),I beleave the Grand am are a diffrent size.As for useing the rear up front for the hubs they should be the same size as the front and yes,they should work,for the hubs only.

For the front GA upgrade you don't use any parts from the rear.

You remove the front rotor/hub and it has to be machined down so the GA rotor will just fit over it.

Then you have to do a little grinding to the area of the caliper mount so it will clear the GA rotor, this does not affect how the GA calpiper will mount.

Give me a few minutes and I'll post a couple pics.

Steve

Keep in mind, this effectivly spaces the front wheels out the thickness of the rotor (~3/8") which is why I have not done the front.

OK, so Goatie you want to use the rear Fiero hubs on the front? I don't see that happening. Chopping off the front rotors would be childplay in comparison.

I was just checking since I have my old rear rotors laying around.

From the pics I can't tell what needs to be ground but I am sure I will see it once I get down there.

I am not too concerned about the fronts sticking out more as I will be dropping it about 1.5 coils and that should reduce the visual effects of the front wheels.

Huh, I never thought about the wheel sticking out farther.

No one has ever said anything and I never noticed.

Is there dimenions somewhere that tell exactly how to machine down the front rotors? I want to do this and my machinist needs to know what all needs to be done. Thanks.

[This message has been edited by tuner2m6t (edited 02-27-2007).]

Measure the inside diameter of the "hats" on the GA rotors, and machine the Fiero hubs accordingly. I think the most popular method is to turn 'em down on a lathe.

[This message has been edited by Blacktree (edited 02-27-2007).]

quote Originally posted by goatnipples2002: I was just checking since I have my old rear rotors laying around. From the pics I can't tell what needs to be ground but I am sure I will see it once I get down there. I am not too concerned about the fronts sticking out more as I will be dropping it about 1.5 coils and that should reduce the visual effects of the front wheels.

Its not about how it looks, its about how it throws off the suspension geometry, your front wheels will be tracking to the outside of the rear wheels.

Its been mentioned several times before, and makes sense, thats why you need longer studs, the front rotors are one piece on the side of the hub, they have no hat that goes over the hub.

I hope you realize that the front and rear track width on the Fiero is not the same. The rear wheels have a wider track. Even with the added thickness of the GA rotors in front, the rear track will still be wider.

quote Originally posted by Blacktree: I hope you realize that the front and rear track width on the Fiero is not the same. The rear wheels have a wider track. Even with the added thickness of the GA rotors in front, the rear track will still be wider.

I've never heard this before, never even heard it suggested. Do you have refrences?

Still, its not what it was designed for, but that would make it much less of a problem.

i could careless about the pushing the fronts out more my main concern is stopping faster and better with the added benefit of way cheaper brake components.

quote Originally posted by goatnipples2002: i could careless about the pushing the fronts out more my main concern is stopping faster and better with the added benefit of way cheaper brake components.

Thats all good and well, assuming you never want to turn during all this... You cant just blindly attack one system and ignore its effects on the rest of the car. I just want to go fast, but im not going to remove the breaking system to save weight. Giving the front end a wider stance is going to induce even more oversteer into a car with way too much already.

dont worry about the 1/2" added width. 1/4" per side. just changing tire widths makes bigger changes than this insignificant amount.
and - it is a pontiac after all - wider is better
anyways - people also have stiffer springs, stronger shocks & poly bushings.

quote Originally posted by Pyrthian: dont worry about the 1/2" added width. 1/4" per side. just changing tire widths makes bigger changes than this insignificant amount. and - it is a pontiac after all - wider is better anyways - people also have stiffer springs, stronger shocks & poly bushings.

Thats a good point, on my 88 I run wider tires in the rear than the front, and one could even compensate for the added rotor width by selecting the appropriate tire sizes.

quote 86GT3.4DOHC said: Giving the front end a wider stance is going to induce even more oversteer into a car with way too much already.

Actually, the Fiero (in stock form) has too much UNDERsteer. The GM engineers built massive understeer into the suspension to counteract the rearward weight bias, and the trailing-throttle oversteer (in the '84-87 suspension). Besides, moving the front wheels 1/2" further apart isn't going to have any noticeable effect on the understeer/oversteer equation.

I learned about the different front/rear track widths when I looked at my Fiero's tire tracks in the dirt. I already knew the rear of the car (the body) was wider than the front. So when I noticed that the rear tire tracks were spaced further apart, it didn't surprise me. I never took any measurements, though. Grab a tape measure and see for yourself.

quote Originally posted by fierohoho: Here's a pic of a completed rotor with new studs. The reason for the new studs is because when the wheel sits on the old rotor/hub there is nothing between it and the rotor/hub. When you do this upgrade you now have a GA rotor between the hub and the wheel so you need a slightly longer stud than stock. I don't have the exact length but measure a stock one and add the thickness of the GA rotor. The machined hubs can be installed back on the spindle and if you were careful you can use the old bearings a races.

Do you have a part number for the studs that you used. And maybe even what store it was that you got them from. thanks
dustin

The standard longer replacement studs are Dorman part number 610-323 or Advance Auto part number 98501. Napa has them too as 323. They are listed in their computers as longer Fiero studs. 12mm X 1.5 thread

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What he said.

quote Originally posted by Hudini: The standard longer replacement studs are Dorman part number 610-323 or Advance Auto part number 98501. Napa has them too as 323. They are listed in their computers as longer Fiero studs. 12mm X 1.5 thread

+ for you man.