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brake upgrades, looking for more info by PerKr
Started on: 01-18-2007 06:47 AM
Replies: 60
Last post by: PerKr on 06-29-2008 05:25 PM
Greg Z
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Report this Post02-27-2007 06:17 AM Click Here to See the Profile for Greg ZSend a Private Message to Greg ZDirect Link to This Post
 
quote
Originally posted by PerKr:

Money is an issue, even though it shouldn't be when it comes to brakes. If money was not an issue for me, I'd be going with Held Motorsports big brake kit with new spindles, but that would cost more than the whole car...

Anyway, what about spindle and hub upgrades? With new front spindles and separate hubs from a different car (maybe an Opel Manta), maybe a brake upgrade could be done without changing the offset?


Exactly, I have to admit I've always been surprised how much brake upgrade cost!

 
quote
Originally posted by lawrence:

My favorite brake upgrades are the cross-drilled brake lines. They really keep the fluid cool during hard braking. This also reduces the force required to push the brake pedal.

-L



do you have a link to these?
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lawrence
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Report this Post02-27-2007 09:17 PM Click Here to See the Profile for lawrenceClick Here to visit lawrence's HomePageSend a Private Message to lawrenceDirect Link to This Post
 
quote
Originally posted by Greg Z:

quote
Originally posted by lawrence:

My favorite brake upgrades are the cross-drilled brake lines. They really keep the fluid cool during hard braking. This also reduces the force required to push the brake pedal.

-L



do you have a link to these?


I made them myself. I started small -- used a 1/8" drill, then worked my way up to 1/4". I think that's a little too much, though, because the pedal was way too soft.

-L

------------------

WebElectric Products

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PerKr
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Report this Post03-31-2007 08:51 AM Click Here to See the Profile for PerKrClick Here to visit PerKr's HomePageSend a Private Message to PerKrDirect Link to This Post
ok, seeing as how I finally got one hub/rotor off the car I figured I might as well push this back up to the top...

I'm going to spend some time now measuring the hub and trying to make a CAD model of it and then see what can be done about the offset issue. If someone has already measured the hub and/or the axle, now would be a great time to chip in and share some measurements and save me some time and headaches

update: have most of the measurements and will start making a CAD model tonight. Some measurements are bound to be off due to my limited equipment but I hope I have most of them right.

[This message has been edited by PerKr (edited 03-31-2007).]

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Austrian Import
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Report this Post03-31-2007 02:25 PM Click Here to See the Profile for Austrian ImportSend a Private Message to Austrian ImportDirect Link to This Post
 
quote
Originally posted by lawrence:

My favorite brake upgrades are the cross-drilled brake lines. They really keep the fluid cool during hard braking. This also reduces the force required to push the brake pedal.

-L



lol
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PerKr
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Report this Post04-01-2007 03:45 AM Click Here to See the Profile for PerKrClick Here to visit PerKr's HomePageSend a Private Message to PerKrDirect Link to This Post
modelled the hub/rotor last night and it looks decent. missed a couple of measurements, but that's only to be expected.

Right now there are just a couple of measurements I need some help with. The distance from each end to the steps which keeps the bearings in the right position and the heights of these steps (although I have done a rough estimation it would be nice to have this verified). So if anyone has a bearing-less hub/rotor, I would appreciate the input (driving season is approaching so I'm not about to take this car apart to the point where I have to order new parts to get it back together)

*edit* just thought of one problem I expect to encounter once I start looking into doing a new hub. The discs I'm considering are a bit wider and will be sitting about 8mm further in than what you would get doing the "normal" swap (don't want to use the disc as a spacer). There is the possibility that the spindle will get in the way. In that case, maybe the better option is to just make a hub for a 2-piece rotor?

*edit again* took a look yesterday and realized my previous thought on possible clearance problems was, pretty much, dumb as hell, just to let you know. Guess I was too tired to think straight...

[This message has been edited by PerKr (edited 04-02-2007).]

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PerKr
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Report this Post04-05-2007 03:41 PM Click Here to See the Profile for PerKrClick Here to visit PerKr's HomePageSend a Private Message to PerKrDirect Link to This Post
just to bump this up to the top and add some questions...

What cars use/used aluminum calipers? always nice to keep unsprung weight as low as possible...

What cars use/used rear calipers with an e-brake similar to that on the Fiero? We know about the Corvette, are there others?

When doing the (insert donor here) upgrade on all four corners, the donor master cylinder is an obvious choice, but what about the proportioning valve? And what if you upgrade the fronts first? Would the brake bias still be as it should?
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Report this Post04-05-2007 06:07 PM Click Here to See the Profile for PrimarisClick Here to visit Primaris's HomePageSend a Private Message to PrimarisDirect Link to This Post
 
quote
Originally posted by PerKr:
...What cars use/used rear calipers with an e-brake similar to that on the Fiero? We know about the Corvette, are there others?...


Ford Focus SVT has the ebrake in the caliper.
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PerKr
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Report this Post04-09-2007 04:55 PM Click Here to See the Profile for PerKrClick Here to visit PerKr's HomePageSend a Private Message to PerKrDirect Link to This Post
had some spare time this weekend and started putting together an excel file to help calculate the forces acting on the hubs. Unfortunately, I still do not have any idea as to how many G's I would be pulling when braking and/or turning or how high the CoG is...

Something I read is that it's the size of the pistons in the calipers which determines the front/rear brake bias. Well, I'd think that the rotor diameter makes a difference as well (with larger rotor diameter the same clamping force from the caliper will result in a larger moment, thereby making it easier to lock the wheels. You get the most braking when you're almost locking the wheels).
So, I also decided to compare the piston sizes of the calipers which could be considered. Does anyone know the piston sizes for the Fiero calipers? Also, the size of the MC (diameter and volume) is probably a good thing to know.
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jweisman
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Report this Post04-09-2007 06:04 PM Click Here to See the Profile for jweismanSend a Private Message to jweismanDirect Link to This Post
 
quote
Originally posted by PerKr:

had some spare time this weekend and started putting together an excel file to help calculate the forces acting on the hubs. Unfortunately, I still do not have any idea as to how many G's I would be pulling when braking and/or turning or how high the CoG is...

Something I read is that it's the size of the pistons in the calipers which determines the front/rear brake bias. Well, I'd think that the rotor diameter makes a difference as well (with larger rotor diameter the same clamping force from the caliper will result in a larger moment, thereby making it easier to lock the wheels. You get the most braking when you're almost locking the wheels).
So, I also decided to compare the piston sizes of the calipers which could be considered. Does anyone know the piston sizes for the Fiero calipers? Also, the size of the MC (diameter and volume) is probably a good thing to know.


The front caliper piston is 2 inch, the rear caliper piston is 1 3/4 inch, I'm not sure about the MC

[This message has been edited by jweisman (edited 04-09-2007).]

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PerKr
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Report this Post06-18-2007 05:37 PM Click Here to See the Profile for PerKrClick Here to visit PerKr's HomePageSend a Private Message to PerKrDirect Link to This Post
 
quote
Originally posted by jweisman:


The front caliper piston is 2 inch, the rear caliper piston is 1 3/4 inch, I'm not sure about the MC



bumping this thread up again, hoping to get some more info. these figures are for the 84-87 solid rotor calipers, right? What about the 88 calipers?
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PerKr
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Report this Post01-02-2008 10:06 AM Click Here to See the Profile for PerKrClick Here to visit PerKr's HomePageSend a Private Message to PerKrDirect Link to This Post
I'll kick this one back up to the top once again.

First, we need to set something straight: the rear caliper pistons are not 45mm diameter. I measured one of mine and it was 47.6mm. I also measured one front piston and it turned out to be 48.95mm, so 49mm seems correct there. This means that if you wanted to, you could use front calipers on the rear without needing to worry about the brake balance

The second thing we need to do is to find the specifications for the proportioning valve. Does anyone know? Did anyone ever measure the brake line pressure at the front and rear and find this out?
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PerKr
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Report this Post01-03-2008 02:07 PM Click Here to See the Profile for PerKrClick Here to visit PerKr's HomePageSend a Private Message to PerKrDirect Link to This Post
So, here are my thoughts this far:

1) the current brakes are smallish, and in my case the e-brake is out of order and parts are costly around here

2) I want to upgrade the brakes anyway

The original brakes are pretty much identical between the front and rear ends. Same size calipers (well, ok, slightly smaller at the rear) and rotors. A proportioning valve, the setting of which is unknown, reduces (limits) pressure for the rear.
Let's compare it to the Ferrari 308: MC 22mm (Fiero 25.4mm), Front caliper piston 48mm (49mm), rear caliper piston 38mm (47.6mm), prop valve setting 0.7 (unknown).
So, if the 308 can use 48mm pistons with a 22mm MC, with the 25,4mm MC we should be able to use pistons with the same total area as if we used single-piston sliding (or dual-piston fixed) calipers with 57mm pistons.

Calculations will show you that the 308 gets more clamping force at the front. If we disregard any prop valves, the Fiero has more clamping force at the rear. now, we do have that prop valve, and I would guess it's set at about 0.5, but I don't know. My calculations tell me that the prop valve of the 308 reduces pressure enough that if I had 38mm pistons on the Fiero and removed the prop valve, I would get slightly more clamping force than the 308 gets with prop valve installed. That's really good news, as it means e-brake calipers with 38mm pistons can be used.

Personally, I have no need for extremely big brakes, so here is the setup I'm considering at this time:

Front calipers: Wilwood forged billet dynapro (or similar Wilwood 4-pot calipers with 35.1mm pistons)
Rear calipers: VW Golf IV rear calipers (aluminium sliding caliper with 38mm piston and parking brake function)
Master cylinder: OE Fiero (a future alternative would be to downsize to 22mm MC to increase clamping force)
Proportioning valve: Wilwood (or similar) adjustable proportioning valve.
Rotors: 280-295mm vented rotors (possibly solid for the rears)

I'm working on making CAD models of the parts for the front to see if things will fit within my rims. I'd prefer to find that out before buying any parts
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Report this Post04-14-2008 08:16 AM Click Here to See the Profile for FieroBrad87Send a Private Message to FieroBrad87Direct Link to This Post
...

[This message has been edited by FieroBrad87 (edited 04-14-2008).]

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hklvette
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Report this Post04-14-2008 02:24 PM Click Here to See the Profile for hklvetteSend a Private Message to hklvetteDirect Link to This Post
Has anyone considered Subarus as a source for brake rotors? Most of their cars use 5x100 wheels, and have far superior brakes to the fiero originals. I am not sure if the calipers would fit, or if the factory fiero calipers would fit over a vented rotor, but i thought i'd throw that idea out there.
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Report this Post04-14-2008 04:50 PM Click Here to See the Profile for Austrian ImportSend a Private Message to Austrian ImportDirect Link to This Post
 
quote
Originally posted by hklvette:

Has anyone considered Subarus as a source for brake rotors? Most of their cars use 5x100 wheels, and have far superior brakes to the fiero originals. I am not sure if the calipers would fit, or if the factory fiero calipers would fit over a vented rotor, but i thought i'd throw that idea out there.


I always wondered about that myself. Or VW, or Audi brakes/rotors. The bolt pattern is correct, and all that would be needed is an adapter plate (bracket), correct?

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Report this Post04-15-2008 08:36 AM Click Here to See the Profile for RixthetrickClick Here to visit Rixthetrick's HomePageSend a Private Message to RixthetrickDirect Link to This Post
 
quote
Originally posted by hklvette:

Has anyone considered Subarus as a source for brake rotors? Most of their cars use 5x100 wheels, and have far superior brakes to the fiero originals. I am not sure if the calipers would fit, or if the factory fiero calipers would fit over a vented rotor, but i thought i'd throw that idea out there.



Been done here in Australia, Subaru Liberty GT rotors with Willwoods on the front. I have just purchased some Australian made 3 piece rims that were originally for WRX Imprezza, the one made before USA got them (the 2 door STI version is still legendary). I will soon know if they are the same offset. Either way with 3 piece rims you can transform them by simply unbolting the dishes off the centre, replacing them and make them whatever offset and width you like within reason. I have also bid on and won a set of front 2 pot WRX calipers on Ebay here... It's going to be all fun from here on in. Distinct difference in Australia, if you want different brakes, you take it to a Main Roads Dept. certified engineer, he does the math and about $1K later as well as whatever modifications he requires you to make you get a modification plate that allows your car to be roadworthy enough to be registered.

Limiting yes, but it's nice to know that other people are also driving cars that can and have meet safety requirements; after all, we share the roads in potentially lethal projectiles.

To install Subaru rotors on an 84-87 Fiero, have the disc turned off the front hub/rotor, if you're clever enough to buy the Subi (excuse my Aussie slang) rotors beforehand you can have the hubs machined to perfectly fit just inside the Subi's. I strongly suggest applying some anti-rust, anti-seize product between the contact surfaces between the hub and the rotor, one day you may just want to seperate them to replace the rotor. Or you could have them machined with clearance to circumvent an incident of rust binding them.
The centre hole being just as important as the wheels studs, because it's supposed to be load bearing as well as centering is actually exactly the same as the Fiero!
Cool huh? No concentric rings needed! Thanks Subaru.

This will however affect the front track (making it the width of the mounting surface of the Subaru rotors) wider, which also means that you will need to replace the wheels studs (wheel bolts, I believe you call them stateside?) There was another thread in PFF where a guy doing a Corvette brake setup got his wheel studs for $1 a piece, I got a quote from FieroStore @ $1.25 which is probably where I will source mine with some other bits for my big toy.

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Austrian Import
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Report this Post04-18-2008 03:09 PM Click Here to See the Profile for Austrian ImportSend a Private Message to Austrian ImportDirect Link to This Post
$ figure cost for that estimated?
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PerKr
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Report this Post04-18-2008 04:26 PM Click Here to See the Profile for PerKrClick Here to visit PerKr's HomePageSend a Private Message to PerKrDirect Link to This Post
 
quote
Originally posted by Austrian Import:


I always wondered about that myself. Or VW, or Audi brakes/rotors. The bolt pattern is correct, and all that would be needed is an adapter plate (bracket), correct?


Correct, all you need are caliper adapters and possibly something to help the VW rotors center properly. The Fiero share both the 5x100 boltpattern and the ET35 with most of the cars made by VW, so we should be able to use VW calipers (which appear to be 48mm front and 36-38mm rear) and rotors. Quite easy to get hold of here as well, although I'm not sure where to get the mounting brackets...
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Report this Post04-18-2008 04:54 PM Click Here to See the Profile for Austrian ImportSend a Private Message to Austrian ImportDirect Link to This Post
 
quote
Originally posted by PerKr:


Correct, all you need are caliper adapters and possibly something to help the VW rotors center properly. The Fiero share both the 5x100 boltpattern and the ET35 with most of the cars made by VW, so we should be able to use VW calipers (which appear to be 48mm front and 36-38mm rear) and rotors. Quite easy to get hold of here as well, although I'm not sure where to get the mounting brackets...


How many pots are in the calipers on VW's?

I have no experience with out-of-the box brake swaps, but would the '84-'87 Fiero people benefit from a group buy on the machined adapter brackets?
If yes? - We need to somehow come up with the best bang/buck - best performance non-GM brake swap mostly off the shelf parts with a 5x100 bolt pattern (or requiring the least expensive modifications) we all can agree upon.

[B}It should meet the following:[/B]

* Approx correct brake bias - that would work on a Fiero
* 13"+ rotor size equivalent (or near that mark)
* Fairly easy to find at boneyards/eBay/car forums related to donor brake setup
(opt: * a master cylinder and/or mc-booster combination (that would fit in the stock fiero location with little/no modification)
* brake lines (incl. braided steel) should be easily mountable on the Fiero
* be affordable to most interested in the group buy

-- please add more if I forgot any constraints --


_____________

I'm wondering if somebody could help us with the math/machining calculations for this. Then we could agree on the best combination and get a group buy for the brackets (and if necessary centering rings) going to drive down the costs. (maybe even a group buy for the machined down rotor - if necessary/feasible)

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Report this Post06-29-2008 03:39 PM Click Here to See the Profile for D2inDFWClick Here to visit D2inDFW's HomePageSend a Private Message to D2inDFWDirect Link to This Post
OOPS! Posted in the wrong thread!

[This message has been edited by D2inDFW (edited 06-29-2008).]

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PerKr
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Report this Post06-29-2008 05:25 PM Click Here to See the Profile for PerKrClick Here to visit PerKr's HomePageSend a Private Message to PerKrDirect Link to This Post
 
quote
Originally posted by D2inDFW:
So tell me, is all the noise and criticism about a few grams of missing metal and two ugly, but unseen holes really justified? Balance your tires and wheels and most of this thread is negated.


???

I have been trying to keep up with this thread, though it seems to be very close to dying most of the time, and I don't get this post. Did I miss something here?

and what's up with the fixation on LARGE rotors and LARGE calipers? Is it just the bling factor?
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