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Looking for possoble problems (SE brake upgrade)

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Old Oct 10, 2004 | 08:07 PM
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Looking for possoble problems (SE brake upgrade)

Okay...I'm trying to find a CHEAP way back into an FC. I've been trying to sell my bikes off or trade them for a nice GXL/GTU/sport/S5 but with little luck. I've wanted something with 5 lugs...just for the LSD option and the better brakes...mostly the better brakes. However, not having luck (as said)...and SE's are a dime a dozen.

So here's what I'm considering...considering the appeal of the 4-lugs being the LIGHTEST FC's...:

I only want the better brakes of the 5-lug setups...so why not improve the brakes of the 4-lug setup and be happier with a cheaper 7? What I'm contemplating is a twin caliper setup for the 4-lug cars. Basically it's going to be two SE calipers on each rotor, 180* from one another. I've done MANY setups like this on motorcycles...but that's a completely different game.

I'm thinking that it should only be done on the fronts, as putting the much force against the rolling parts of the car might cause you to lose control if you brake hard (learned with motorcycle setups). I also think that putting the two extra calipers on the fronts only wouldn't be so much of a stress on the system as to require a different booster.

I have the means to make the brackets and all...so can anyone see any potential problems I might encounter?
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Old Oct 10, 2004 | 09:20 PM
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also...if someone could just confirm this for me...

There were only two types of brake setups available on the FC, right? The single and quadpistons, correct?
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Old Oct 10, 2004 | 10:27 PM
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why not just make brackets to adapt the 4 pistons to your 4 lugs if you wanna keep them?
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Old Oct 10, 2004 | 10:41 PM
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...partial list of parts I have...

single piston brake caliper assemblies: 18
quadpiston brake caliper assemblies: 0


Also, as I said, I believe that using two single piston assemblies (plus steel braided lines) would allow you to leave the rest of the braking system unmolested.
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Old Oct 10, 2004 | 10:47 PM
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Originally Posted by Makenzie71
...partial list of parts I have...

single piston brake caliper assemblies: 18
quadpiston brake caliper assemblies: 0


Also, as I said, I believe that using two single piston assemblies (plus steel braided lines) would allow you to leave the rest of the braking system unmolested.
I'd wager a good bet that adding two single piston calipers have a higher surface area then one 4 piston, or right close to it. That means your change in pedal feel will be about the same. The primary issue with this is the custom fabrication of the lines and stuff, a lot of headache, for a solution that will net you similiar or worse results (probably worse, because of the rotors) to the TII/GXL setup. You can probably pick up rebuilt calipers from an auto parts store for under 100 bucks total, and just make brackets if you want them. I run TII brakes with a "base" mater cylinder, and my pedal feel is perfectly fine, just use good quality fluid and bleed them properly, and -near- stock pedal feel is retained. Also, adding braided lines will probably offset a lot of the pedal feel loss of the 4 pistons anyway-

More power to you if you want to pioneer this setup, and I'm not doubting it's feasability, just it's merit.

Last edited by digitalsolo; Oct 10, 2004 at 11:02 PM.
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Old Oct 10, 2004 | 11:02 PM
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I can't see the braided lines offsetting pedal feel any more than on a regular setup. I don't think that the dual single piston caliper setup will have as much coverage as the dual quadpiston setup. The individual pads are larger than the single piston pads, and there's two sets on each rotor. Also, brake lines would just be a matter of buying either four steel braids or yanking two lines off my car, going to the hardware store and buying a couple of brass "T's" and bolting it up.

...this came over as much more of "you're wrong and I'm not gonna listen" kind of post than I intended. This is stuff I've played with a little bit before, though. I'm just looking for potential problems like possible stress on the rotor or space restrictions or complications with the rest of the braking system and such...

Last edited by Makenzie71; Oct 10, 2004 at 11:04 PM.
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Old Oct 10, 2004 | 11:43 PM
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what will you do as far as ensuring proper hydraulic pressure to each caliper, and do you think the stock master cylinder will suffice? Also, with the added surface area, this will more than likely heat up the rotors a lot faster, and reduce their ability to dissipate heat.

sounds like a lot of work, and a lot of added weight to the car. stock 4 piston caliper is already plenty of braking power for street driving. Upgrading rotors and pads can already make for a very capable and efficient braking system.
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Old Oct 10, 2004 | 11:54 PM
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Originally Posted by BlackR1
what will you do as far as ensuring proper hydraulic pressure to each caliper, and do you think the stock master cylinder will suffice? Also, with the added surface area, this will more than likely heat up the rotors a lot faster, and reduce their ability to dissipate heat.

A propper T setup will ensure that each caliper gets the same pressure from the master cylinder. I'm sure the stock SE master cylinder will sufice. That's one of my goals for this project...make it to where the rest of the braking system can remain un-molested. I don't think the stock calipers are taxing enough, though. With the install of steel braid lines, it should work great. If the fluid in the system is kept up, and an added precaution with maintanance (more parts = more things to break), and they should work fine...but experience will prove it or disprove it.

Drilled/slotted rotors would have to be used for best results...but I also don't think heat would be that big of an issue. You don't think that the stock quadpiston setups heat the rotors pretty quick?


sounds like a lot of work, and a lot of added weight to the car. stock 4 piston caliper is already plenty of braking power for street driving. Upgrading rotors and pads can already make for a very capable and efficient braking system.
20lbs to the car. I also don't have any quadpiston calipers laying around to play with...much less the mastercyliner and such I need to install with them.
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Old Oct 11, 2004 | 12:04 AM
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Sounds like it'd work... only problems I can think of are heat and fitting everything in there securely. I know you say heat shouldn't be an issue, but I still think it might be... especially under heavy short term use... in other words, autox. You can't compare it to the 4 piston because the 4 piston uses less braking surface and less force... or at least I'm assuming since these are going to effictively be a larger surface area 4 piston brakes... and you might have pressure issues... meaning, you might end up locking these 4 piston wheels before the back ones have very good braking power at all.

I'd definately worry about the heat though... I mean, you do have more experience with this like you said... but that's a lot of brake pad covering the rotors, it's not gonna have a lot of area to vent.

--Gary
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Old Oct 11, 2004 | 12:09 AM
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I think the quadpistons heat them up quicker from the additional friction from the higher clamping force, but they have more free surface area on the rotor to dissipate heat. stock brakes cover about 20% of the rotor surface area, adding another brake will mean 40% of the surface area is covered, which equals to less heat dissipation. This also leads into the problem of the brake fluid heating up
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Old Oct 11, 2004 | 12:12 AM
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You're fine, I don't think you came off bad at all.

It's an interesting idea, for sure.

As I said before, I have TII brakes and the small MC, and the pedal feel is fine, so if you're worried aobut that, don't be.

If you build it, put up some pics. Sounds neat.
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Old Oct 11, 2004 | 12:18 AM
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I was looking for a pic of the dual caliper setup...which is what I thought the quadpiston setup was but it's apparently different...don't know. I DO know that my setup will have less coverage on the rotor than the dual caliper setup I planned on duplicating...I guess it have about 25% more than the quadpiston setup.
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