Hey pff been a lurker for a while. Gained a ton of info and ideas and inspiration from the forum. Super helpful stuff around here.
I wanted to give a bit of real info that I had a difficult time finding hard evidence of while doing my own research.
I just finished a lebaron brake upgrade on my ‘85 GT (which was converted to a fastback some years ago by one of the previous owners) I did a full brake system rebuild minus the booster. I used the fierospace brackets front Seville calipers on all 4 corners (no ebrake, I know people take issue with that but it never worked well anyway since I bought it so this was my solution. Ive always just used wheel chocks if I needed too) I used brakeperformance.com slotted zinc coated Daytona (Lebaron) rear rotors and raybestos street performance pads with the full size ‘94 full size blazer master and new lines and hoses all around from the Fiero store. All solid products of really really good quality. Minus the master but more on that later.
The thing about this setup I had trouble finding concrete info on was A if it would fit and B will matched size calipers actually limit the lockup issues with balanced caliper sizes. Good news is they will just fit under the stock 86-87 GT 15” lace wheels. It’s a tight fit but it absolutely fits. No sticky wheel weights inside your wheels on this setup. Also there was no trimming required for the rear pads using the fierospace brackets which was a nice surprise. I’ve read in some posts from the past that some grinding of the wheels was necessary to make clearance for the caliper which never sounded right to me but that wasn’t the case in my situation. I haven’t put the setup through its paces yet driving in anger so time will tell about the lockup thing but under normal driving mix of city and highway it feels great. A bit lighter than factory but pedal travel and feel are very good and pretty well balanced.
The only real issue I ran into was a bad brand new ACDelco master cylinder right out of the box. Was bubbling like mad out of the primary chamber and line no matter how many times I tried to bench bleed both on the bench in a vice looping the lines, on car, after I thought I had it bled I hooked up the lines and was trying to bleed between the master and prop valve all I ever got was a soft pedal and bubbles out of the primary line. Took the master back off bench bled it again and all seemed good. I bought speed bleeders tried solo bleeding with a stick flooring the pedal and even had a helper pressing and holding. It never gave me a solid pedal and only ever shot air out. I must’ve gone through 5 or 6 bottles of brake fluid trying to bleed this system but just could not get the damn thing to work right. Replaced with another new ACDelco master same part number and bam no more issues. Bench bled it and with the speed bleeders I was able to bleed the whole system rather quickly. So let it be a warning I guess. New from a quality brand name doesn’t necessarily mean good.
After experiencing a couple unsettling brake fade incidents while driving it relatively hard on the local mountain roads with the factory setup I spent a really long time researching and planning for a winter brake upgrade this past year. Debating whether to go with rebuilt factory stuff with new ebrake hardware, grand am setup all around or with Seville ebrake rears or Seville/lebaron front and rears with and without ebrake. Reading everything I could find on all of these different setups. All of which were relatively comparable pricing depending on options. I read about a bunch of lockup issues with both of the upgrade setups using mismatched calipers. It was a tough choice especially feeling uncertain the Lebaron setup would even fit under the stock wheels I decided to just go for it and went with matching sized front and rear calipers to attempt to avoid the proportioning/lockup issues under heavy braking with the smaller rear calipers not wanting to fiddle with a different bias/ prop valve in line and to avoid any and all of the quirks of an auto adjusting caliper mounted ebrake. I figured if they didn’t fit I’d just save for larger wheels and do it all in one shot. The upgrade-ability was a really big sell for me too. Gm metric calipers have a very nice upgrade in the Wilwood D154 kits. If this setup is as solid as it seems that option may help to try and recoup some of the added weight too. No idea if those will fit under the oe wheels but time may tell. For right now I’m pretty pleased with how everything worked out.
Thanks for reading and I hope this will help someone else out who is maybe on the fence about trying this setup
