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Grand Am upgrade by fieroluv
Started on: 11-16-2006 09:20 PM
Replies: 49
Last post by: CopperBender on 01-13-2008 02:20 PM
fieroluv
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Report this Post11-16-2006 09:20 PM Click Here to See the Profile for fieroluvClick Here to Email fieroluvSend a Private Message to fieroluvDirect Link to This Post
Ok Now I am completely confused. I am in the middle of a Grand Am brake upgrade, and was just reading in the cave how this is a horrible idea. It started getting way too technical and lost me in all the physics of it all. I read the postings that he linked to but that got way too technical as well. Can anyone just explain without going into physics whether or not I should finish this or just go back to OEM. The hubs have been matched to the rotors and have the calipers already. I was only planning on doing the front brakes. I still don't have a master cylinder yet. So I'm not sure what to get, the Blazer MC or a stock one and modify it to work. But haven't really seen anything on how to modify the stock fiero MC to work. They started getting into physics again.

Really all I want to know is what I can use that is safe. If I should just bite the bullet and buy stock hubs, rotors and calipers I will. But really didn't want to spend that much money.

Any advise would be helpful. If there are mods out there to make the stock MC work are there pictures available. On the postings I was looking at are from 2001 and the pictures are invalid links.

Thanks.
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AP2k
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Report this Post11-16-2006 09:46 PM Click Here to See the Profile for AP2kClick Here to Email AP2kSend a Private Message to AP2kDirect Link to This Post
Should just do the S10 booster upgrade. Lots easier and people say it works as well as a Corvette brake upgrade. I got some new rotors for $20 and the booster shouldnt cst you too much more than that.
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fieroluv
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Report this Post11-16-2006 09:58 PM Click Here to See the Profile for fieroluvClick Here to Email fieroluvSend a Private Message to fieroluvDirect Link to This Post
So are you saying keep the grand am brakes and add an s10 booster with S10 MC or Fiero MC?
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KeithGT
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Report this Post11-16-2006 10:42 PM Click Here to See the Profile for KeithGTClick Here to Email KeithGTSend a Private Message to KeithGTDirect Link to This Post
Wait, booster, or master cyl?
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fierohoho
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Report this Post11-16-2006 10:50 PM Click Here to See the Profile for fierohohoClick Here to Email fierohohoSend a Private Message to fierohohoDirect Link to This Post
I did the Grand Am upgrade a few years back on my 84SE with an automatic transmission.

All I did was the rotors and calipers with the stock front rotors machined down to fit the Grand Am rotors.

I never messed with the booster or master cylinder and have not had any problems.

The car stops great and I have since done it to 2 other cars of mine with no problems.

The only thing I don't have with this upgrade is an emergency brake but it is an auto and with you only doing the front you would still have the E brake.
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Darth Fiero
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Report this Post11-17-2006 12:40 AM Click Here to See the Profile for Darth FieroClick Here to visit Darth Fiero's HomePageClick Here to Email Darth FieroSend a Private Message to Darth FieroDirect Link to This Post
You should NOT try using a Blazer M/C with the Grand Am brake upgrade. Why? Allow me to explain...(will try not to get to technical)

It is true that the Grand Am brake calipers use slightly larger pistons than the OE Fiero units. This means that it is going to require slightly more fluid to move the caliper piston the same distance as it did with the smaller OE Fiero's piston. However, the difference is NOT great enough to require that you install a larger-bore M/C, like the Blazer unit.

If you already have a good OE Fiero brake M/C, then the installation of Grand Am brakes will increase the braking effectiveness vs. pedal effort. If you install the Blazer M/C, or any M/C that has a larger bore than the OE Fiero unit, then brake pedal effort will go up while braking effectiveness goes down. It is true that with the addition of GA brakes on the Fiero using the stock Fiero M/C you will get more pedal travel before the brakes engage. However, I have not found this to be an issue.

On my 87 Fiero, I am running the GA brakes on all 4 corners and I am using an OE-replacement stock Fiero brake M/C. I have absolutely no problems with excessive pedal travel (it is actually less than it was when I got the car because I replaced the M/C which was failing). My car stops with very little pedal effort, I would say about 1/3 less pedal effort is required vs. stock Fiero brakes for 84-87. A while back before I knew better I tried the Blazer M/C and my pedal effort about doubled. This means it took a lot longer to stop the car unless I stood on the brake pedal.

Now I know some people complain about low brake pedal in their Fieros and think the Blazer unit is going to correct it. The no.1 cause of low brake pedal in Fieros is faulty rear brake calipers that are out of adjustment. The OE Fiero rear brake calipers adjust only when the e-brake is used, and according to some GM info I found, the e-brake must be actuated at least once a week. If not, the racheting mechanism inside these calipers will freeze up and will no longer work even if you started using the e-brake again. The only way to correct this problem would be to rebuild the caliper or replace it.

The no.2 cause of low brake pedal issues in Fieros is a faulty brake master cyl which results from a lack of maintenance. Regular maintenance specifies that brake fluid should be flushed every 3 years. When was the last time yours was done? If this is not done the brake fluid will break down which will result in premature wearing of the pistons and bore of the brake m/c as well as the calipers. If you have a failing master cylinder, you will know because when you step on the brake pedal, fluid will shoot out of it (if it didn't have the cap on). Very little fluid should move in the brake fluid reserviours when you hit the brakes on a good system. It is NOT normal to have fluid shooting up with any force after the first inch or so of pedal travel. If this is the case on your car, then you need to replace your brake M/C.

Again, to recap...

-Master Cylinders like the Blazer unit have larger bores and pistons which move more fluid volume at the cost of decreased hydraulic advantage (higher pedal effort for same system pressure). I would only recommend using the Blazer M/C if you are using bigger brakes than GA or OE Fiero equipment (IE: Camaro, Corvette, Cadillac, and multi-piston calipers).

-Smaller bore master cylinders like the OE Fiero unit have less volume of flow but increased hydraulic advantage (lower pedal effort for same system pressure)

-Larger diameter caliper pistons will require more fluid volume to move them however the larger surface area of the piston results in increased force transmitted to the brake pads with the same brake system pressure pressure vs. a smaller piston caliper.

If you are installing calipers with much larger piston surface area than stock you should use a larger bore master cylinder. The system should be balanced, however. You don't want to sacrifice too much pedal effort in order to retain a "high pedal", likewise, you don't want to sacrifice pedal travel to attain lower pedal effort. Now you can install a vacuum booster that is more powerful in order to offset a high pedal effort issue, but make sure you aren't just doing this to work around a problem you have with the brake system like a bad m/c with an internal leak or OE Fiero rear calipers that are out of adjustment.

Correctly working and adjusting rear Fiero calipers should have enough e-brake clamping force to keep the car from moving and you should NOT be able to pull the e-brake all the way up before the car stops. My 87 SE with the 3.4 DOHC 5-speed has what I consider to be a perfectly operating e-brake system. It will literally lock up the rear tires at slower speeds and it is almost impossible for me to pull the e-brake handle all the way up to the last click with one hand.

-ryan

------------------
power corrupts. absolute power corrupts absolutely.

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wftb
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Report this Post11-17-2006 01:31 AM Click Here to See the Profile for wftbClick Here to Email wftbSend a Private Message to wftbDirect Link to This Post
i have the rcc lebaron /camaro brake upgrade and use the stock fiero master cylinder .works great.
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3800superfast
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Report this Post11-17-2006 01:49 AM Click Here to See the Profile for 3800superfastSend a Private Message to 3800superfastDirect Link to This Post
Ran across this--may help--not sure.. http://www.fierofocus.com/articles/tt-grandambrakes.html
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fieroluv
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Report this Post11-17-2006 07:08 AM Click Here to See the Profile for fieroluvClick Here to Email fieroluvSend a Private Message to fieroluvDirect Link to This Post

Thanks Darth that explains a lot. So I'll be ok with just buying a stock master cylinder then. The car didn't have one when I bought it. Looks like I'll probably need to purchase rear calipers as well. God only knows when the last time was that the ebrake was ever used.
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fieroluv
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Report this Post11-17-2006 07:09 AM Click Here to See the Profile for fieroluvClick Here to Email fieroluvSend a Private Message to fieroluvDirect Link to This Post

fieroluv

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Member since Jul 2002
 
quote
Originally posted by 3800superfast:

Ran across this--may help--not sure.. http://www.fierofocus.com/articles/tt-grandambrakes.html



Doesn't really apply to me since I'm only doing the fronts. But thanks anyway.

And the only reason I'm doing the fronts is because the car came without any suspension on it. So I figured what the heck, everything is already off, might as well go ahead and upgrade it.

[This message has been edited by fieroluv (edited 11-17-2006).]

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3800superfast
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Report this Post11-17-2006 07:44 AM Click Here to See the Profile for 3800superfastSend a Private Message to 3800superfastDirect Link to This Post
 
quote
Originally posted by fieroluv:
Looks like I'll probably need to purchase rear calipers as well. God only knows when the last time was that the ebrake was ever used.

Didn`t know the year/model/ect so I hit in the middle, the rear ones are 1/2 way down and also towards the bottom, last time I checked --even auto/zone couldn`t beat rock autos prices.
http://www.rockauto.com/catalog/x,carcode,1249107,parttype,1704
If you have problems with e-brake cables/hardware
http://www.secureleadercom.com/fsstore/default.asp?bodystyle=1&topdeptnumber=44&searchBit=3&dept=377
http://www.secureleadercom.com/fsstore/default.asp?bodystyle=1&topdeptnumber=44&searchBit=3&dept=0&map=Parking_Brake

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Report this Post11-17-2006 08:56 AM Click Here to See the Profile for PyrthianClick Here to Email PyrthianSend a Private Message to PyrthianDirect Link to This Post
 
quote
Originally posted by fieroluv:
Doesn't really apply to me since I'm only doing the fronts. But thanks anyway.

And the only reason I'm doing the fronts is because the car came without any suspension on it. So I figured what the heck, everything is already off, might as well go ahead and upgrade it.


I did only the fronts on mine. I need the rear hand brake, or I would do them too. They do work good. But, the front brakeing is stronger than it should be. I can still stop faster than I could before from a 70 MPH brake dive, than I could with the stock brakes. But, thats not a fair test, being the stock brakes were the original stock brakes, and the Grand Am brakes are brand new & fresh. I have been looking at getting a proportioning valve to try to force a little more rear braking. I tried removing the spring from the existing prop valve, but its hard to tell if it helped. I think it did, but not alot.

Overall, I think doing all four with Grand Am brakes is a great way to go, if you dont need the hand brake.
doing just the fronts is OK. stopping distance from high speed is decreased, which is a good thing. but, the brake bias does seem to need more rear braking - and once you get that straight - the braking distance will go down even more. Mid-engine/Rear Engine cars need rear braking.
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Arns85GT
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Report this Post11-17-2006 09:13 AM Click Here to See the Profile for Arns85GTClick Here to Email Arns85GTSend a Private Message to Arns85GTDirect Link to This Post
 
quote
Originally posted by Darth Fiero:

You should NOT try using a Blazer M/C with the Grand Am brake upgrade.

A while back before I knew better I tried the Blazer M/C and my pedal effort about doubled. This means it took a lot longer to stop the car unless I stood on the brake pedal.

-Master Cylinders like the Blazer unit have larger bores and pistons which move more fluid volume at the cost of decreased hydraulic advantage (higher pedal effort for same system pressure).

-Smaller bore master cylinders like the OE Fiero unit have less volume of flow but increased hydraulic advantage (lower pedal effort for same system pressure)

-Larger diameter caliper pistons will require more fluid volume to move them however the larger surface area of the piston results in increased force transmitted to the brake pads with the same brake system pressure pressure vs. a smaller piston caliper.

If you are installing calipers with much larger piston surface area than stock you should use a larger bore master cylinder.

-ryan



Ryan, when you installed your Blazer M/C you must have done something wrong. I drive 2 cars. #1 is an Olds, still under warranty, with power brakes and #2 is the Fiero with Grand Am brakes/Blazer MC. The Fiero pedal pressure is almost as good as the Olds' power brakes. The Fiero stops extremely well with noticably better than stock pedal pressure. I am using ceramic pads on both cars.

When you install your Blazer MC you do not increase the plunger travel. You increase the amount of fluid being moved by the plunger. In theory it takes more force to move, however, the pistons in the calipers are 2&1/8" across and take up the additional fluid moved. The whole thing balances out.

I repeat, you do not have more pedal pressure. In fact, guys who have driven my Fiero who have stock brakes in good working order, notice how easy and solid the brakes are. I have driven a Fiero recently with Grand Am fronts and Fiero rears, (it was safetied) and the brakes took more pressure and and sucked noticably when compared to mine. The owner noticed it too. I mean that without the Blazer MC it was a little scary.

Now to be fair, PBJ did my conversion and he does really good work.

The Grand Am upgrade is a very good one. As for the ebrake issue, I am working on a Cadillac conversion for the rears with 2" pistons and it will balance out well and include a top mounted bleeder and ebrake. Essentially, it will have the same ebrake upgrade as the LeBaron upgrade, using a different bracket and bleeders on top.

Arn
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fieroluv
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Report this Post11-17-2006 01:03 PM Click Here to See the Profile for fieroluvClick Here to Email fieroluvSend a Private Message to fieroluvDirect Link to This Post
I think I'll take a chance and just buy the Fiero master cylinder, and if I don't like the way the pedal is, just go back to fiero brakes. I don't want to have to buy the blazer master cylinder and not like that and then have to buy the fiero master cylinder and the fiero rotors and calipers. But that'll still be a little while yet. My lowering springs I ordered are on backorder till 12/15.
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Report this Post11-19-2006 08:28 PM Click Here to See the Profile for KeithGTClick Here to Email KeithGTSend a Private Message to KeithGTDirect Link to This Post
Wow. I guess every car ive ever done brakes on has a failing master cylinder. Ive never had a MC NOT shoot fluid if the pedals pressed to quickly, including after just changing it on my fiero. Huh...
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Darth Fiero
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Report this Post11-19-2006 09:04 PM Click Here to See the Profile for Darth FieroClick Here to visit Darth Fiero's HomePageClick Here to Email Darth FieroSend a Private Message to Darth FieroDirect Link to This Post
 
quote
Originally posted by Arns85GT:


Ryan, when you installed your Blazer M/C you must have done something wrong.....

When you install your Blazer MC you do not increase the plunger travel....


With all due respect, I never said you did increase pedal TRAVEL with the Blazer M/C and no I didn't do anything wrong when I tried using one in my car. As a matter of fact, using a stock OE replacement Fiero M/C with my 4-wheel GA upgrade, my Fiero stops much easier (least amount of pedal effort) than ANY other vehicle I have driven. I have taken the classes and countless training courses on hydraulics and hydraulic braking so I think I have a pretty good idea how things work concerning hydraulic brakes.

The plungers in the Blazer M/C are larger than the stock Fiero units. This means they are going to move more fluid with the same pedal travel vs. the smaller plungers in the Fiero M/C. However, because they are larger, this means less pressure will be exerted on the brake fluid vs. the smaller plungers in the stock Fiero M/C with the same pedal effort. This, of course, assuming you are using the same diameter of the caliper pistons in the comparison. This is simple hydraulic theory. If you don't believe me, go look it up.

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Oreif
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Report this Post11-19-2006 10:35 PM Click Here to See the Profile for OreifClick Here to visit Oreif's HomePageClick Here to Email OreifSend a Private Message to OreifDirect Link to This Post
 
quote
Originally posted by Darth Fiero:


However, because they are larger, this means less pressure will be exerted on the brake fluid vs. the smaller plungers in the stock Fiero M/C with the same pedal effort. This, of course, assuming you are using the same diameter of the caliper pistons in the comparison. This is simple hydraulic theory. If you don't believe me, go look it up.


Arn, Darth is correct.
What Darth is saying is that since it is a larger diameter pistion, The force is spread out. Think of it as pounds per square inch.
If you have a 1 sq/in piston with 10 lbs of pressure pushing it you have 10 lbs per square inch. If it's a 2 sq/in piston with 10 lbs pushing it, You now have 5lbs per square inch. Brakes don't work by amout of fluid but more on the clamping pressure applied. So with the larger M/C you have less travel but it requires more pressure to achieve the same clamping pressure at the brake pads than if you had the Fiero M/C.

In Arn's case it may feel better only because there is less travel, But if you were to measure pressure applied to the brake pedal, You would find out that more is required. When people drive his car they mistake the shorter travel as being better and more solid feel but they don't realize they are actually applying more pressure on the pedal.

For those who want to learn more click on the "Ogre's Cave" link at the bottom and go to his "Brake Upgrade" article. He has a very good write up on things you should be aware of before upgrading the brakes.

Here is the link: http://home.comcast.net/~fierocave/

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Report this Post11-20-2006 11:50 AM Click Here to See the Profile for ChumpClick Here to visit Chump's HomePageClick Here to Email ChumpSend a Private Message to ChumpDirect Link to This Post
I believe that it has been recomended to also use the s10 booster in order to counter the added pedal effort of the blazer mc.
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Report this Post11-20-2006 12:35 PM Click Here to See the Profile for Arns85GTClick Here to Email Arns85GTSend a Private Message to Arns85GTDirect Link to This Post
Thanks Darth and Oreif. And, yes I have the S10 booster which explains alot. And maybe it is a case of a lead foot?

Arn
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Report this Post11-20-2006 01:13 PM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageClick Here to Email BlacktreeSend a Private Message to BlacktreeDirect Link to This Post
To answer the original question, I believe The Ogre is a bit paranoid when it comes to the Fiero brakes. No offense to him, but my personal experience has proven the Grand Am upgrade to be not only a viable upgrade, but better than stock in almost every aspect*. I'm running Grand Am brakes with braided hoses front and rear, with the stock Fiero master cyl and booster. Yes, there is some slack in the brake pedal. But the brakes work wonderfully. I can lock all 4 wheels at a whim.

If you only replace the front brakes, you will shift the brake bias a little more to the front, as mentioned above. That can be a hair-raising experience if you need to make a panic stop on a wet road.

* If you're worried about unsprung weight, the Grand Am brakes add approximately 8 lb per wheel in the front and 4 lb per wheel in the back, as compared to stock '84-87 brakes.

[This message has been edited by Blacktree (edited 11-20-2006).]

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Report this Post11-20-2006 06:38 PM Click Here to See the Profile for jstrickerClick Here to Email jstrickerSend a Private Message to jstrickerDirect Link to This Post
People commonly get confused about pedal force and travel. It's not all that complicated if you can picture a few things in your mind.

First, picture a syringe that has a bore of 1/2". You have a pusing on it that will transmit exactly 500 pounds of force on the end of the syringe. The area of the plunger of the syringe is approximately 2/10 of a square inch. You are therefore exerting 2,500 pounds per square inch on the fluid coming out of the tip of the syringe.

Now, picture the exact same thing, only the bore of the syringe is 2" in diameter. Now you have an area on the plunger of 3.14 square inches and since the force has remained the same, you are only exerting 159 pounds per square inch, or about 1/16 the pressure.

The difference is that if you move each plunger 3 inches, in the first case you have moved 6/10 of a cubic inch of material and in the second case, you move over 9 cubic inches of material, or 15 times as much volume.

Do you see the relationship here? Bigger means more flow, less pressure for the same input force and travel, smaller means less flow with more pressure for the same input force and travel.

In the case of the Grand Am upgrade, I have variations on several cars, each done for a specific purpose. On the race car, I have the GA upgrade with the Blazer M/C and the stock booster. I don't want real easy brakes but I also want a reasonable amount of stroke. If the brakes were too easy lockup on the autocross track or the road course would be very easy to obtain, and we don't want that.

On the Finale, I put the Blazer M/C on the car after driving it with all new brakes with the stock M/C. I found the stroke to be too long for MY personal preference and with everything new and hi performance pads, I could lock the brakes at will. I am considering putting the S10 booster on the car to make the pedal force a little less for when the wife drives the car because she complains the brakes are too stiff.

One thing I would be very hesitant to do is just the front brake upgrade with either master cylinder. Although many have done it, and seem to like it, it IS going to give you early rear brake lock up because the GA calipers have larger pistons and when you move the same amount of fluid as the stock and Blazer M/C does, the rear brakes are going to apply first, and harder. As long as you aren't into very heavy braking, you might never notice it. Where you WILL notice it is if the roads are slick and/or wet and locking up the rear of a Fiero is nothing to play around with if you're not ready for it.

Always have a REASON for doing something with a system as critical as your brakes. A properly adjusted set of rear calipers, good pads front and rear, and true rotors is MORE than capable of locking up the wheels on the car, although the pedal throw is longer than I like. If you repeatedly abuse them on the track or autocross course then the stock brakes will fade from heating, but I've never had an issue with that in normal street driving. I have the Grand Am upgrade on the racecar for the vented rotors more than anything else because they are much more resistant to brake fade than the stock, solid rotors, especially if you duct cold air to the center of the rotors. Other than that, there isn't a lot of difference in well maintained stock brakes and the Grand Am brakes since the rotors are the same diameter and the pad area is roughly the same.

John Stricker
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Hudini
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Report this Post12-08-2006 09:42 PM Click Here to See the Profile for HudiniClick Here to Email HudiniSend a Private Message to HudiniDirect Link to This Post

I also would like the GA upgrade for my brakes. One thing is confusing me. Several posts mentioned the S10 booster. Randy Agee's article says:

You may also use the full size Blazer MC mentioned in this article with approximately 1/2" less pedal travel and slightly more pedal effort, or you may use a 92-93 S10/S15 Master cylinder for near OEM pedal travel and effort.

Randy Agee

Not S10 booster - S10 master cylinder. Anyone try this MC?
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Report this Post12-08-2006 10:17 PM Click Here to See the Profile for NewGTClick Here to Email NewGTSend a Private Message to NewGTDirect Link to This Post
I have done the front GA upgrade with the Blazer MC, stainless braided brake lines and rebuilt stock rear calipers on my 86 GT. While I like the improvement, it does take maximum pedal effort to get lock-up. I have not experienced the dreaded rear wheel lock-up, perhaps because of the rear-weight bias of the fiero.

One thing I don't think anyone has mentioned yet is that the front brake upgrade increases the wheel offset and thus increases the scrub radius. This technically will affect the handling, particularly bump-steering and recentering of the steering after a turn, and not in a positive way. Since I did my upgrade prior to driving the car (this was a total restoration over three years) I do not have a reference point to just how much of an effect it makes on the handling.
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Report this Post12-08-2006 10:24 PM Click Here to See the Profile for HudiniClick Here to Email HudiniSend a Private Message to HudiniDirect Link to This Post

Has anyone tried the S10 master cylinder? (not full size blazer MC)
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Report this Post12-10-2006 12:37 PM Click Here to See the Profile for olejoedadClick Here to Email olejoedadSend a Private Message to olejoedadDirect Link to This Post
I used the S-10 MC, GA rotors and calipers, braided hoses and new lines. Kept the stock proportioning valve and booster. Works like stock except the braking is improved about 500%. No problems - bolt it up and go! ...or, er, stop, I guess...
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Hudini
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Report this Post12-10-2006 06:28 PM Click Here to See the Profile for HudiniClick Here to Email HudiniSend a Private Message to HudiniDirect Link to This Post

Very cool, just what I needed to know. Thanks.
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Blacktree
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Report this Post03-07-2007 03:18 PM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageClick Here to Email BlacktreeSend a Private Message to BlacktreeDirect Link to This Post
I just replaced my stock Fiero m/c with the early '90s S10 m/c and didn't notice any difference. Not only is the pedal effort the same, but there's still about an inch of slop in the pedal. Not only that, but the S10 m/c looks exactly like my Fiero m/c. It even has the same reservoir.

What gives here?

[This message has been edited by Blacktree (edited 03-07-2007).]

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WhiteDevil88
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Report this Post03-07-2007 03:45 PM Click Here to See the Profile for WhiteDevil88Click Here to Email WhiteDevil88Send a Private Message to WhiteDevil88Direct Link to This Post
 
quote
Originally posted by fierohoho:

I did the Grand Am upgrade a few years back on my 84SE with an automatic transmission.

All I did was the rotors and calipers with the stock front rotors machined down to fit the Grand Am rotors.

I never messed with the booster or master cylinder and have not had any problems.

The car stops great and I have since done it to 2 other cars of mine with no problems.

The only thing I don't have with this upgrade is an emergency brake but it is an auto and with you only doing the front you would still have the E brake.


+1. No problems at all. Never. And Grand Am/Beretta parts are CHEAP!

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Blacktree
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Report this Post03-08-2007 04:02 PM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageClick Here to Email BlacktreeSend a Private Message to BlacktreeDirect Link to This Post
After some research online, it would seem that the stock Fiero master cylinder and the early '90s S10 master cylinder have the same size cylinder bores. So switching to a S10 m/c is a waste of time and money.

I replaced that S10 master cylinder with a '94 Chevy Blazer unit. The slop in the pedal is gone, and braking effort is increased. I can deal with the increased pedal effort. Actually, I was afraid of unintentionally locking up the brakes during a panic stop (which I've already done a couple times) with the Fiero master cylinder.

[This message has been edited by Blacktree (edited 03-08-2007).]

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fieroluv
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Report this Post03-19-2007 05:55 PM Click Here to See the Profile for fieroluvClick Here to Email fieroluvSend a Private Message to fieroluvDirect Link to This Post
Not to totally change directions with this but I finally got my suspension together and getting around to installing this. I'm a little confused, after reading several pages of archives on this topic I'm not seeing anything regarding the banjo bolt hitting the shock. Am I the only person seeing this problem? When I turn Lock to Lock it hits right before the steering stop. I suppose if I swap calipers left to right, I wouldn't have this problem, but that would put the bleeder on the bottom of the caliper and that would make it impossible to bleed all of the air out.
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fierohoho
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Report this Post03-19-2007 07:26 PM Click Here to See the Profile for fierohohoClick Here to Email fierohohoSend a Private Message to fierohohoDirect Link to This Post
That's interesting, can you post a pic or two so we can see the setup?

If not you can e-mail them to mee and I'll post them.

I did not have that problem with my 84 setup.

Steve
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fieroluv
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Report this Post03-20-2007 07:13 AM Click Here to See the Profile for fieroluvClick Here to Email fieroluvSend a Private Message to fieroluvDirect Link to This Post
I'll try and get a picture tonight.. I may have to work pretty late tonight, so if not tonight maybe tomorrow. My car is currently up on ramps getting ready to pull the engine, but I can jack it up and pull a wheel off to snap a picture.
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Pyrthian
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Report this Post03-20-2007 07:26 AM Click Here to See the Profile for PyrthianClick Here to Email PyrthianSend a Private Message to PyrthianDirect Link to This Post
yes, my banjo bolt hits the shock also.
on the drivers side.
but, it only does this when the suspension is at full extension, so I ignored it.

I assumed if my front wheels are off the ground, and I have the wheel cut all the way to the right - I wont be needing my brakes anyways.....

actually, I ground down the brake line head to give it more room. it still can hit, but you really gotta be in a weird situation - like I said - front wheels off the ground, and wheel cut all the way right
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fieroluv
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Report this Post03-20-2007 09:24 AM Click Here to See the Profile for fieroluvClick Here to Email fieroluvSend a Private Message to fieroluvDirect Link to This Post
Yeah, you are probably right. I haven't looked at it with the suspension loaded. Only with the car sitting on jack stands and suspension fully extended. That makes me feel a little better.
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Arns85GT
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Report this Post03-20-2007 11:45 AM Click Here to See the Profile for Arns85GTClick Here to Email Arns85GTSend a Private Message to Arns85GTDirect Link to This Post
 
quote
Originally posted by jstricker:

If you repeatedly abuse them on the track or autocross course then the stock brakes will fade from heating, but I've never had an issue with that in normal street driving. I have the Grand Am upgrade on the racecar for the vented rotors more than anything else because they are much more resistant to brake fade than the stock, solid rotors, especially if you duct cold air to the center of the rotors. Other than that, there isn't a lot of difference in well maintained stock brakes and the Grand Am brakes since the rotors are the same diameter and the pad area is roughly the same.

John Stricker


Interesting note given all the debate on other threads. If your race car brakes are doing the job on the track, then the Grand Am conversion must certainly be all you need for the street. Personally, I have the standard MC with the Blazer Booster and all 4 Grand Am rotors. It certainly is a good system. It will be interesting to see what effect the Cadillac rotors have when I get them on the rear.

Arn
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Pyrthian
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Report this Post03-20-2007 12:46 PM Click Here to See the Profile for PyrthianClick Here to Email PyrthianSend a Private Message to PyrthianDirect Link to This Post
 
quote
Originally posted by Arns85GT:
Interesting note given all the debate on other threads. If your race car brakes are doing the job on the track, then the Grand Am conversion must certainly be all you need for the street. Personally, I have the standard MC with the Blazer Booster and all 4 Grand Am rotors. It certainly is a good system. It will be interesting to see what effect the Cadillac rotors have when I get them on the rear.

Arn


thought it was lebaron rotors w/cadillac calipers? either way - hows this coming along?
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Arns85GT
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Report this Post03-20-2007 02:46 PM Click Here to See the Profile for Arns85GTClick Here to Email Arns85GTSend a Private Message to Arns85GTDirect Link to This Post
The prototype brackets are done, and the finished product is still in production.

Fitting to the 14" turbo wheel is still a problem. I should know pretty soon.

The Cadillac caliper is 1/8" bigger than the Grand Am which should put a bit more pressure to the front.

I'll post the install when things get there.

Arn
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PerKr
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Report this Post08-06-2007 05:31 PM Click Here to See the Profile for PerKrClick Here to visit PerKr's HomePageClick Here to Email PerKrSend a Private Message to PerKrDirect Link to This Post
 
quote
Originally posted by jstricker:

One thing I would be very hesitant to do is just the front brake upgrade with either master cylinder. Although many have done it, and seem to like it, it IS going to give you early rear brake lock up because the GA calipers have larger pistons and when you move the same amount of fluid as the stock and Blazer M/C does, the rear brakes are going to apply first, and harder. As long as you aren't into very heavy braking, you might never notice it. Where you WILL notice it is if the roads are slick and/or wet and locking up the rear of a Fiero is nothing to play around with if you're not ready for it.


While I sort of agree that the rear brakes may apply earlier, I do not get why they would squeeze the rotor any harder. We do have the same pressure throughout the whole system, right? Simple physics then tell me that F=p*A. Let A1 be the piston area for the fiero rear caliper and A2 be the piston area for what ever caliper you decide to try on the front. If A2 > A1 then p*A2 > p*A1, or F2 > F1.
Taking it a bit further, taking a closer look at the master cylinder, I see one option which would give one pressure for the rear and another for the front and that would be if the master cylinder is divided into two portions with a direct mechanical link between the MC piston for the rear and MC piston for the front (meaning that the front and rear MC pistons will always travel the exact same distance). Is that how the fiero MC is designed?

Probably the safest way around the brake bias problems when upgrading would be to have separate master cylinders for front and rear calipers...
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Brint
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Report this Post01-12-2008 12:42 AM Click Here to See the Profile for BrintClick Here to Email BrintSend a Private Message to BrintDirect Link to This Post
I can't help but wonder about this statement. I changed the brake lines to stainless steel on mine and I shot brake fliud all over my spare tire, inside the hood, and on my headlights (what a mess). Is my MC shot? Now that I think about it, would that occur if the emergency brake was engaged? Because I think I had it engaged which means I'll probly have to re-bleed my brakes. I certainly don't remember it doing that when I installed new calipers Any thoughts?
 
quote
Originally posted by KeithGT:

Wow. I guess every car ive ever done brakes on has a failing master cylinder. Ive never had a MC NOT shoot fluid if the pedals pressed to quickly, including after just changing it on my fiero. Huh...


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RWDPLZ
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Report this Post01-12-2008 01:23 AM Click Here to See the Profile for RWDPLZClick Here to visit RWDPLZ's HomePageSend a Private Message to RWDPLZDirect Link to This Post
When I did the Grand Am upgrade on my rear brakes and started to bleed the system, I left the cap off and the fluid shot up like a geyser out of the master cylinder. Brakes still work fine, installed them back in August.

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1984 Fiero SE

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