Anybody know if I can replace 88 rear calipers with a bigger piston caliper? And if so, where would I get it? I know the 84-87 use "GM Metric" or commonly called d156 calipers, IIRC. Is there a size designation for the 88 calipers?
The 88 brakes where pretty good stock. Some people just get slotted/ drilled rotors and better quality pads. I bought 2 new sets of 88 front calipers. You lose the E-brake by running them on the rear, but I don't trust them. Mine started dragging my second day owning the car and almost caught on fire.
On a related note. Ogre's cave has a lot of great info for such things. Click
getting an 88 with a 88 swap. Car has standard front suspension, so I worry about brake balance. Can't afford 12 corvette upgrade. have a full front "cradle" with held drop spindles and lebaron brake upgrade. Want larger pistons on the rear 88 10.43 Inch rear to get better balance. Lebaron : 11.26 inch with 2 3/8 or 2.5 inch caliper 88 : 10.43 inch with 2-ish inch caliper pistons. caliper is even set 0.18 inch from disk edge making it effectively smaller.
Someone was selling adapters that allowed you to use Corvette rotors with the stock calipers (I know Rockcrawl did at one point as I have those (but he has fallen off the edge of the planet), but there was someone else. Bolt these on with redrilled Corvette rotors and you are done.
Also sounds like you have a non-88 front end that you want to swap in - you know, most people go the other way to have the 88 suspension. That being said, I am sure you will have no problem selling the stock 88 front suspension setup.
[This message has been edited by Mickey_Moose (edited 12-18-2014).]
I'm sorry. Let me clarify. I am getting a second Fiero. It's an 86 1/2 GT with the 88 rear cradle upgrade. In my garage I have the front crossmember from yet another 86 Fiero that had the held drop spindles and Lebaron brake upgrade. I would put the extra front crossmember with drop spindles and Lebaron brakes on the GT, but only if I could use larger calipers with the std 88 rear brake discs and cradle. Right now the GT has it's original 84-87 style front suspension and brakes AND a 88 rear cradle swap with 88 stock rear brakes. Problem is that if I swap in the Lebaron/Held upgraded front end, then that's WAY too much front brake. Only option is a replace the rear caliper with a bigger piston caliper or find brackets to do a Lebaron rear 88 upgrade
If i were to do the Lebaron upgrade, I would need to increase rear line pressure. I thought the prportioning valve only worked to decrease pressure. I read somewhere to not ever place an adjustable proportioning valve on the front brake line. So, unless thats wrong: 1) use a different reverse the lines if the master cylinder sends more fluid to the front brakes than the rear 2) sleeve the front chamber and use a smaller piston 3) bore out the rear chamber and use a larger piston 4) both 2 & 3 5) add a second tandem single chamber master cylinder to feed just the back brakes with and adjustable tandem arm to fine tune the amount of fluid the tandem MC pushes 6) Make cailper adapter brackets to do a Lebaron swap on the rear. (Has anyone done this and if so, any diagrams for the brackets? 7) do 6 but use 88 brake calipers (Has anyone done this?) If I had my choice, for now, I would do 7 because I would retain close to original brake bias even using a 84-87 MC instead of a 88 MC. And i can upgrade to a 12 inch kit later. Plus, the held front drop spindles complicates an upgrade of the front discs. I will need to get purchase the brackets from Arraut Motorsports and could end up being quite expensive.
At this time i am working on a bracket that will allow you to bolt on Grand am front calipers to the 88 rear knuckle. You will retain the 88 rear rotor but loose the parking brake feature. I'm doing this for my chumpcar build which is an 85 GT with the 88 rear cradle. Using the grand am swap brakes in the front and back will keep the brake balance. I also found that the 88 rear rotor is slightly larger diameter than the grand am rotor by 3/4 of an inch. If there is an interest in these brackets I might produce some. I would like to at least test them under race conditions to verify they are safe and sturdy.
Originally posted by Knight: 6) Make cailper adapter brackets to do a Lebaron swap on the rear. (Has anyone done this and if so, any diagrams for the brackets? 7) do 6 but use 88 brake calipers (Has anyone done this?) If I had my choice, for now, I would do 7 because I would retain close to original brake bias even using a 84-87 MC instead of a 88 MC.
Thanks Fieroguru. Since I already have all the parts except the adapters for the rear 88 swap, this will be a whole lot cheaper than going to 12 inch brakes, especially since I have original rims.
That being said, I am sure you will have no problem selling the stock 88 front suspension setup.
Gotcha. Another option might to be to use the 88 rear calipers as is and use an adjustable bias regulator instead?
