Hi All,

Seems that I may need to replace the brake booster on my Formula. I have read a few topics here saying that it is a good idea to replce that with a brake booster from...I believe it was a Chevy s-10. This was rather old info, I am wondering if anyone did this or has thoughts on it, or is a stock replacement good enough if yo uhave new but stock brake equipment on the car?

.....and does it have to be from a same year S-10 (ex 88 to an 88) or can they vary?

https://www.fiero.nl/forum/Forum2/HTML/072173.html

I would use the stock booster. All that the S-10 booster "upgrade" does is increase the amount of force applied to the rotor at the same pedal pressure, decreasing the ability to modulate the brakes at the limits of traction, and decreasing pedal "feel". On wet roads this can be dangerous, as it would be easier to lock the brakes in an emergency condition.

quote Originally posted by olejoedad: I would use the stock booster. All that the S-10 booster "upgrade" does is increase the amount of force applied to the rotor at the same pedal pressure, decreasing the ability to modulate the brakes at the limits of traction, and decreasing pedal "feel". On wet roads this can be dangerous, as it would be easier to lock the brakes in an emergency condition.

Have you ever driven your Fiero hard? What you're saying seems unrelated to reality.

The '88's are better, but all years of Fieros are acutely devoid of both good modulation AND the ability to lock tires in the first place. Since I normally "run out of brake boost" when stopping hard in my Formula, I think that a booster upgrade is a capital idea. Because the stock booster runs out of boost, pedal force bows the firewall and completely eliminates any semblance of good limit feedback or limit modulation in stock Fieros. Decreasing pedal load by increasing boost should work very well.

Don't knock it till you try it.

[This message has been edited by Will (edited 01-23-2009).]

No, Will, I just putt-putt around in my Fieros..........

I have not had the issues you describe with any of the nine Fieros that I have owned after the brake systems were rebuilt. The two that I currently drive (86 SE, GA upgrade all around and a Formula V-8) have excellent braking power, and more importantly, controll in the wet.

Sounds like there are differing opinions on the effectiveness of this mod. I have read in other places on this site that people think it is a worthwhile and fairly easy mod to do. Others have said there is no real difference. I have replaced the rotors, pads, and put in SS brake hoses....wondering if with this will be sufficient with the stock brake booster or if there would be any real difference in performance and feel with the S10 upgrade?

quote Originally posted by sleebbie: Hi All, Seems that I may need to replace the brake booster on my Formula. I have read a few topics here saying that it is a good idea to replce that with a brake booster from...I believe it was a Chevy s-10. This was rather old info, I am wondering if anyone did this or has thoughts on it, or is a stock replacement good enough if yo uhave new but stock brake equipment on the car?

Sleebie,

What makes you think your booster is bad?

I have not seen too many posts on this but the first thing I would do is check the booster filter. I just rebuilt the brakes on my 86 and checked the filter - it was nearly plugged. Also check the entire line from booster to rotor. Mine had some crud built up in it. Took it off and flushed it out with solvent, blew ari through it. Rebuilt the calipers, new higher end pads, drilled an slotted rotors and braided flex lines. Car stops on a dime now. Would it be perfect railin down a curvy road - porbably not but for everyday city traffic - I think it will be fine. Worth a look anyway!

Anybody who says that replacing their fiero brake booster with one from a truck makes no difference doesn't know what they're talking about. All the info you need is in that link if you really want to do it.

One of the advantage of the car forums is you can research different post on a subject you are interested in and draw your own picture !! and also get to read the scruffier dogs scuffles..I especially enjoy this part..
I concider the brakes on the 88 Fiero great ,, the stock system will stop the car in under 130 feet from 60 to 0 with good pads,, this is very good for a 1988 car..
I would think you have never had a problem with stop distance with the 88 system you have now !! It never hurts to have better brakes , the ability to stop from 60 to 0,, 5 feet sooner could save you plowing into the rear of a prius driven by a 17 year old genius geek female just accepted into Harvard & breaking her neck.
Use the search feature at the upper right of the page to locate different post on this subject,,and this should help your decision making ..

quote Originally posted by PaulJK: Anybody who says that replacing their fiero brake booster with one from a truck makes no difference doesn't know what they're talking about. All the info you need is in that link if you really want to do it.

I haven't tried this, but my Opinion is that it can't hurt, and the Stock Fiero brakes need all the help they can get.

I know that the cars are 20+ years old, but even with all new stock parts the braking is pitiful by today's standards.

quote Originally posted by olejoedad: No, Will, I just putt-putt around in my Fieros.......... I have not had the issues you describe with any of the nine Fieros that I have owned after the brake systems were rebuilt. The two that I currently drive (86 SE, GA upgrade all around and a Formula V-8) have excellent braking power, and more importantly, controll in the wet.

Can you lock up the tires on dry pavement?

Really good point about the filter I will check, in addition to better brake fluid, a couple of times bleeding the system, etc. The guy working on my car thought there was a hissing sound coming from the brake booster and suspected a leak, but now we are sidetracked on another problem (broked head bolts) and have not gotten back to the brake booster. I think the guys who say the S10 upgrade cant hurt are right I see no downsides to it other than the bit of time spent to do the job (which doesnt seem all that hard anyway). Def agree brakes on an 88 car in general are not going to be the same as today, but yeah mine basically didnt stop at all so I decided to replace everything! LMAO about the Prius....I hate those things anyway.

Yes, Will, I can lock the brakes on dry pavement. Not desirable, but possible.