Calipers

[TheJet-09]

Swartzman - To further explain my "left side only" brake scenario, I'd start by admitting I am of the driving style where I dump the throttle and jab the brake on corner entry (at least when the track is heavy). I unfortunately still drive that way today, but back to my story....when qualifying that night (this had to have been around 1998), I heard a clunk come from the rear as I came off of four, but didn't think too much about it...heading into one on the second lap, I realized what the clunk was - the RR caliper mount broke, which allowed the caliper to spin along with the rotor, which in turn broke the brake hose (= no more rear brakes). Hitting the brakes going into one then locked up the fronts, which sent me into the wall, which tore up the RF. Due to time and lack of parts, we just plugged the RF and RR brake hoses and ran the feature with just left side brakes. I have driven with the RF shut off but have never liked it...seems to "jerk" the front end to the left and I've just never liked that feel...also had concerns of what it would do if I was in traffic and had to get on the brakes hard - might end up in the infield! With just the left side brakes I felt like the car had a subtle "pull" to the bottom on entry, but possibly due to the significant reduction in overall braking ability. One last thing I'd point out is that the rear end was locked (spool). Despite that, you most certainly can tell when only one rear wheel has brakes. I'd ask this...we can alter the drive/influence of our rear wheels (left vs. right) under power by changing the difference in weight/force on each tire (LR heavy vs. RR heavy), even though the two wheels are "locked together." Wouldn't the same hold true under braking as well?

[kaij15]

I understand. I know it is used in different applications. It has it's advantages and disadvantages. More of a Driver preference thing. Maybe L/R would work better with a RF shutoff? Since your pressure gain would be to the RR and not lock up the LF (usually going to mostly if not ALL rear brake with RF shutoff in a F/R system). Just a thought. Maybe Billet or Matt49 has an opinion on this?

[billetbirdcage]

I'd ask this...we can alter the drive/influence of our rear wheels (left vs. right) under power by changing the difference in weight/force on each tire (LR heavy vs. RR heavy), even though the two wheels are "locked together." Wouldn't the same hold true under braking as well?

It does, but:

You have to have a change in tire loading from the brakes to make that work. If you have a brake floater or caliper mounted to birdcage, it is loading the tire through that devise and adding load to the tire which will effect the traction of the tire and therefor may pull car one way or the other.

Now granted even with a clamped to the axle brake bracket as you brake it tries to unload the rear end through the torque arm. But I'm not sure there is enough force there to unload the LR more enough then the RR to notice a difference, I could be wrong but I'd agree with swartzman I don't think you'd see a difference on a locked axle with clamped brakes.

Seeing it was that long ago for JET, it's possible that he had both calipers on the birdcage as it was still reasonably common back then but going away at that time. If both were on the birdcage, I'd expect that you could see a difference if you unhooked the right. 50% less braking power but the LR would get the loading from the caliper pushing down on the cage thru the bars and by unhooking the RR you removed that on that side. So theoretically the LR would have gained more load then the RR (just from braking) and should cause the car to be looser (LR has more traction to slow car from engine braking and regular braking) just from a rear brake standpoint. How noticeable is going to depend on bar angles and how much it's loading the LR.

To answer the OP's question, it's not uncommon to use different size calipers front to rear. If you a heavy trail braker you may like smalls on the front and big on the back. I'd personally prefer to stay with big all the way around unless your running a sanction that you having trouble making weight and need to shave weight. It's not so much you going small on the front, but just bigger on the back some like or are fine with small brakes. I generally just don't like them as once you've had big brakes it's hard to go backwards, IMO.

Keep in mind also just cause they are large brakes doesn't mean they stop better. As a generalization:

1. Small cast calipers don't stop as good as big cast calipers
2. Small billet calipers seem about the same as big cast calipers
3. Small billet calipers don't stop as good as billet big calipers

Obviously it varies among brands, but gives you a basic idea.

[TheJet-09]

^^^ Billet - As always, great information! I didn't even consider the difference in B/cage mounted versus axle mounted. I can't recall which it was but would have to believe they were mounted on the birdcages. It wasn't my car although I ended up buying it later on, and I'm certain we weren't even on the LR behind stuff yet. Because of my antiquated driving style, I've considered going to a floater on the LR to keep it up on the bars on entry. I just haven't made the investment $/time wise out of fear I'd be no better off than I currently am.

[Matt49]

This is what I was eluding to in post #18 but a great explanation as usual from billet.

The place where I felt the biggest difference in floating versus not was on a big flat track where you were really on the brakes for longer durations.

I believe Lazer chassis have frame mounting options to run a separate brake floater rather than floating the caliper on the birdcage.

[swartzman]

Matt I think your right, I think Lazer does have them..

[hucktyson]

Spike Logue from wildwood swears testing has proven that large calipers do not produce more force than small calipers .... The only difference is that the pads last longer .... That isn't my option it's wilwoods ...

[Matt49]

Correct. Caliper and pad size don't matter (much).
Piston size certainly does though.

[hucktyson]

Yes since the line pressure is constant the force exerted on the pad is greater when you have a larger piston .

[25drtrkr]

Your not going to find anybody who has a adjustable left to right brake system. What you will find is people do have a adjustable right front brake. I'm not saying someone may have something like that but no one I am aware of.

A friend of mine who is a crewchief on an asphalt team, told me awhile back, they have been running this with good success. They run Port City cars so Im sure it came from them. I have looked into doing this on a dlm and believe have found an easy way to try it. I believe you could install a small ball valve into the brake lines going to the lf and lr calipers. Then adjust as necessary. Of course, this would be for testing only. If it shows any gains, then you could modify your brake line system to make it permanent.

[swartzman]

One of the things that upsets a car and gives drivers more fits is being able to regulate how much pressure your hitting the right front with.. wilwood makes something for that. They make a lever style proportioning valve, simple to use, simple to install, click it forward or pull it back. Depending on how much rf brake ur actually needing.