Best modern braking system upgrade? (Page 1/4)
Squall86GT OCT 15, 10:43 PM
What’s the best setup for a modern braking system? I want it to brake like a modern sports car. I’ve got aftermarket 16” wheels so there’s some more room in there? Are there other GM braking parts that fit well and accomplish this? Thanks!
Squall86GT OCT 15, 11:44 PM
How does this kit compare to modern car brakes?
https://www.fierostore.com/...px?s=56004&d=379&p=1
pmbrunelle OCT 15, 11:51 PM
Your question is very broad...

You should identify some key metrics.

Once you have a list of characteristics comparing Fiero vs. "modern car", then we can discuss item by item.

For example, here are some possible metrics:
Stopping distance on dry asphalt?
Fade?
Pedal firmness?
Anti-lock braking system?

Make the list of metrics that matter to you.

[This message has been edited by pmbrunelle (edited 10-15-2020).]

Mike in Sydney OCT 16, 01:11 AM
Read the section on brakes in Ogre's Cave on this site. It give you loads of data and allow you to make an informed decision.

FWIW, I believe the best and most cost-effective brake "upgrade" is:

1. Make sure that all the calipers are functioning correctly. (You may want to rebuild or replace them all if they are questionable)
2. Make sure your flexible brake lines from the hard lines to the calipers are fresh. Old lines may swell when you hit the anchors. You could replace them with stainless steel braided lines but I've not been able to tell the difference between new braided lines and new rubber lines. (Yes, i know they aren't really rubber.)
3. Install a new Fiero master cylinder, not one with a larger bore like from a Chevy S-10 Pick-up. Make sure you bench bleed the master cylinder before you install it.
4. Install new, high quality brake pads. I like Wagner Thermoquiets.
5. Flush your brakelines and refill the system with new DOT3 fluid.
6. Bleed the brake system. Lots of discussion on the proper sequence but the the generally accepted sequence is LR, RR, RF, LF. (Although I think that there is likely no appreciable difference between LR, RR, RF, LF and RR, LR, RF, LF. I'm going for cover now because this is likely to cause some controversy.)
7. Install a new Chevy S-10 Pick-up brake booster and check valve. You'll need the extenstion from Rodney Dickman (http://rodneydickman.com/product_info.php?products_id=350).

I know there are other options out there. I've got the Grand Am (Fiero Store) upgrade on one of my GT's and the above upgrade on the other. The one described above out-stops the Grand Am every time. It has better feel and it was a lot easier to do.

Have fun, be safe.

------------------
Mike in Sydney

theogre OCT 16, 03:51 AM
Do Not compare Non-ABS Fiero and others to Any ABS AKA "modern braking system" vehicles!
Way to many ABS vehicles have Over Boosted PB and more issues then let ABS "Black Box" to stop any problems w/ OE setup.
Example: Many ABS cars "trip" the BB and that activates ABS even on Clean Dry Pavement. Many ABS "freak out" when turning and braking even at low speed around a city.

Fix/Restore OE brakes w/ Premium Pads like Wagner Thermo Quiet. But Even many "cheap" pads from big big names are better then OE Fiero and other pads even in the 80's resulting in long stopping distance specs publish by GM and others.
See my Cave, Brake Service and rest of section.

SS hoses are a waste and have issues.
Use new "rubber" that meets SAE J1401. Many are sold as "Pro grade" hoses. These Hoses have DOT and SAE printed on the hose.
See rubber brake lines vs stainless steel http://www.fiero.nl/forum/Forum2/HTML/129208.html

Do Not buy "brake upgrades" from TFS. Just ~ maybe ⅔ of the GA crap "upgrade."
Most Other Fiero "brake upgrade" have problems too but not covered in cave because so few bought into them.
Installing these "upgrades" for street cars can cause big legal problems after a wreck in many places. Even if don't have problems w/ cops etc.

Most claim Big Booster is "great" have problems w/ OE booster. Good OE Fiero Booster Does Not need you to "push hard" or "Stand On Pedal" to stop...
When That Happens... Booster could have failed in several ways, 84-86 Booster Filter in the engine bay is full of crap, and more issues making poor brake performance even before 30+ year old brakes can have hydro and other problems.
Some claim "better" for "racing" have no clue what is the real problem. AutoX and some other classes can make PB to run out of vacuum during a race. They need to install a vacuum "tank" or even Electric Vac Pump so PB and rest of car have enough vacuum.
Big Booster can be dangerous more so when you can easily lock the rear axle. Lock brakes Does Not improve braking to start w/ but Lock rear brakes can easily spin the car or worse.

16" and larger rims w/ bigger tires in Fiero have more issues than just braking issues. Big tires, meaning bigger total diameter/circumference, vs OE size for Any vehicle slows the car "out of the hole" and F'ed w/ Speedo and ECM/PCM.
See my Cave, Gear Ratio
Some "newer" vehicles can set Tire Size in the PCM to keep Trans Shift Points etc happy but that won't solve total gearing lose for fat rubber.

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)


The Ogre's Fiero Cave

Will OCT 16, 08:39 AM
What year is your car? '84-'87 have different factory brakes and different mounting than '88's.

Assuming your car is an '84-'87, it has tiny solid rotors and aluminum calipers. In good working condition, they are fine for driving around town or for one panic stop from highway speeds. They are not sporting brakes.
The fact that they are so small means all possible brake upgrades are heavier. As brakes are unsprung weight, this will impact ride quality. I'm guessing that doesn't matter much to you, as you've already done a wheel upsize.

The best combo in terms of keeping weight low while significantly improving capabilities, I've come across is the 11.25" "LeBaron" upgrade. There's been a LOT written about it over the years, so searching this forum and Google should get you info and parts suppliers. This setup uses 11.25" Chrysler LeBaron brake rotors, which have the Fiero 5x100 hub bolt pattern along with GM Metric calipers. GM Metric chassis refers to '80's G-bodies and similar cars and actually has quite a bit of racing hardware built to fit those parts.

Beware, most kit suppliers try to sell you third gen Camaro/Firebird front calipers. You're better off with 4WD S10 front calipers, as they will hook up to the STOCK Fiero hoses. These calipers are iron. If you want to spend more money, Wilwood and other companies make aluminum versions of the GM Metric calipers.

I also installed a larger diameter master cylinder with mine. The pedal is high, firm and easy to modulate.
Also as noted, new DOT rubber brakes lines are just as good as braided stainless brake lines, but are more reliable and less subject to damage and wear during normal use.

[This message has been edited by Will (edited 10-16-2020).]

Blacktree OCT 16, 01:31 PM
Sorry to nitpick, but any modern braking system will have ABS and maybe traction control. Retrofitting that stuff from another vehicle will be problematic, to say the least.

That said, the pre-88 brakes are pretty terrible. There are several upgrades that use vented rotors. And of course, they have different calipers, so the hydraulic system needs to be altered. If you're not familiar with how hydraulic systems operate, you could cause more problems than you solve.

That said, I have personal experience with the Grand Am upgrade (the Fiero Store upgrade uses the Grand Am parts) and the LeBaron upgrade. I personally prefer the LeBaron upgrade. Not only are the rotors larger, but IMO the hydraulics work better. With the Grand Am upgrade, the stock Fiero master cylinder gives you a mushy brake pedal. And after you take up the slack, the brakes can be grabby. With a larger master cylinder, the brake pedal is pretty stiff. You really have to stand on the brakes to make things happen. The hydraulics used with the LeBaron upgrade give a brake pedal feel closer to stock.

For the '88 Fiero brakes, I think all that's needed is larger rotors, and some good pads. People used to make kits that allow the use of 12" rotors with the '88 calipers. I'm not sure if anyone still makes that. But IMO, that would be the ticket for an '88 Fiero.
DimeMachine OCT 20, 06:30 PM

quote
Originally posted by theogre:

Do Not compare Non-ABS Fiero and others to Any ABS AKA "modern braking system" vehicles!
Way to many ABS vehicles have Over Boosted PB and more issues then let ABS "Black Box" to stop any problems w/ OE setup.
Example: Many ABS cars "trip" the BB and that activates ABS even on Clean Dry Pavement. Many ABS "freak out" when turning and braking even at low speed around a city.

Fix/Restore OE brakes w/ Premium Pads like Wagner Thermo Quiet. But Even many "cheap" pads from big big names are better then OE Fiero and other pads even in the 80's resulting in long stopping distance specs publish by GM and others.
See my Cave, Brake Service and rest of section.

SS hoses are a waste and have issues.
Use new "rubber" that meets SAE J1401. Many are sold as "Pro grade" hoses. These Hoses have DOT and SAE printed on the hose.
See rubber brake lines vs stainless steel http://www.fiero.nl/forum/Forum2/HTML/129208.html

Do Not buy "brake upgrades" from TFS. Just ~ maybe ⅔ of the GA crap "upgrade."
Most Other Fiero "brake upgrade" have problems too but not covered in cave because so few bought into them.
Installing these "upgrades" for street cars can cause big legal problems after a wreck in many places. Even if don't have problems w/ cops etc.

Most claim Big Booster is "great" have problems w/ OE booster. Good OE Fiero Booster Does Not need you to "push hard" or "Stand On Pedal" to stop...
When That Happens... Booster could have failed in several ways, 84-86 Booster Filter in the engine bay is full of crap, and more issues making poor brake performance even before 30+ year old brakes can have hydro and other problems.
Some claim "better" for "racing" have no clue what is the real problem. AutoX and some other classes can make PB to run out of vacuum during a race. They need to install a vacuum "tank" or even Electric Vac Pump so PB and rest of car have enough vacuum.
Big Booster can be dangerous more so when you can easily lock the rear axle. Lock brakes Does Not improve braking to start w/ but Lock rear brakes can easily spin the car or worse.

16" and larger rims w/ bigger tires in Fiero have more issues than just braking issues. Big tires, meaning bigger total diameter/circumference, vs OE size for Any vehicle slows the car "out of the hole" and F'ed w/ Speedo and ECM/PCM.
See my Cave, Gear Ratio
Some "newer" vehicles can set Tire Size in the PCM to keep Trans Shift Points etc happy but that won't solve total gearing lose for fat rubber.




Ogre,
I have re-read your comment about the TFS brake upgrade and didn't really understand it.

I am thinking about the GA front brakes for my application which is very specific. Stopping from 114 in the 1/4 is getting a little sketchy with the non-vented front rotor getting pretty hot. I am thinking the GA front rotor might make a decent difference for this purpose as it is vented and has more mass. I understand your concerns about liability and rear lockup issues etc on the street (which can be warm, cold, hot, icy, snowy etc) and lawyers look for any angle they can take in an injury lawsuit.

That having been said, I am interested in your opinion as to what you would do to make your Fiero stop better and safer at the RACETRACK from 114 (and hopefully closer to 120) soon.

Thanks in advance,

Dime

------------------
84/87 NB, 3800SC, E-85, VS Cam, 2.8 Pulley, 4T65E-HD, HP Tuners, AEM Wideband, Regal GS Gauges, S-10 Brake Booster. 1/4 mile -11.85 at 114mph

[This message has been edited by DimeMachine (edited 10-20-2020).]

pmbrunelle OCT 20, 06:46 PM

quote
Originally posted by DimeMachine:
rear lockup issues etc on the street (which can be warm, cold, hot, icy, snowy etc)



The problem with oversized front brakes (without similar matching rear brakes) is premature FRONT lockup.

With an unbalanced setup like this, when you are modulating the brake pedal so the front tires are just on the verge of lockup (the threshold), the rear calipers aren't squeezing very hard. Therefore, you're not getting much rear braking force, despite being at the front tire lockup limit.

The result is that you increase your stopping distance.

I ignored common sense, and I tried the LeBaron with the very different calipers that are typically suggested:
Front: 2.5" bore
Rear: 2.125" bore

It was awful, and not only in rain, but it was terrible in the dry as well (in terms of stopping distance).

I found 2.25" bore front calipers, and braking performance was much better. For short stopping distance, you want all four tires to be at the verge of lockup, with the rears slightly underbraked, so they keep rolling, maintaining stability under braking.

The easy solution to balance the system is to install the GA setup on the rear as well.

If you want a nice balanced setup with a working parking brake, you'll have some head scratching to do. I have no off-hand solution for that, but the big-brake mod I hope do on my Fiero will be balanced and include a parking brake. Some study will be required.

[This message has been edited by pmbrunelle (edited 10-20-2020).]

Mike in Sydney OCT 20, 07:41 PM


If you are determined to do the brake "upgrade" and want to keep it balanced, you can try the Grand Am Rotor / Seville caliper upgrade for the rear. See http://www.fiero.nl/forum/A...130314-2-083566.html for information. This is supposed to allow you to keep a working parking brake.

I can't comment on the efficacy of this system as while I have the parts, I don't have it on either of my GT's yet and in all likelihood won't install them.

------------------
Mike in Sydney