Brake Balance Ideas

[Emagdnim]

Basicly I have discs in the front and drums in the back. I'm looking to get a bit more rear bias. I've seen in my workshop manuel that I have a brake bias valve for adjusting front and rear pressure disturbustion. What I'm afraid will happen is that by takeing power from the front(which have more effective brakes) and giving it to the rear(which have the less effective drums) That I will lose overall braking power. The brakes right now cause a moderate level of understeer(not helping with brake drifts). My question to you all is do think it would be wise to sacrifice overall brake power for brake balance? I think that better balance would give more control. But lose of power would mean you would have to start to brake sooner or have to brake harder.

[nissanguy_24]

Re: brake balance ideas

Originally posted by Emagdnim
Basicly I have discs in the front and drums in the back. I'm looking to get a bit more rear bias. I've seen in my workshop manuel that I have a brake bias valve for adjusting front and rear pressure disturbustion. What I'm afraid will happen is that by takeing power from the front(which have more effective brakes) and giving it to the rear(which have the less effective drums) That I will lose overall braking power. The brakes right now cause a moderate level of understeer(not helping with brake drifts). My question to you all is do think it would be wise to sacrifice overall brake power for brake balance? I think that better balance would give more control. But lose of power would mean you would have to start to brake sooner or have to brake harder.

Well your brake biasing doenst "take power" from the other brakes, but takes hydrallic power driving the brakes. Your front brakes wont get any weaker, they will simply require more pedal pressure to be as effective as they are now. At least the way i understand it.

As far giving up overall braking power for brake biasing. I was reading grass roots racing a few months back (had drifting on the cover) and they had an excellent artical on brake biasing. They stated one of there project cars barely shortened its stopping distance a few feet dispite the fact they went to huge brakes. a massive upgrade over stock. But when they adjusted the brake biasing and dialed it in they cut something like 20-25 feet off the stock stopping distances.

Also remember the number one most important factor in your brake effectiveness is your tires. Try playing with your air pressure or even consider stickier rears to effectively make your rear brakes work harder... well these are just some random ideas. Dont know how acurate is.

Honestly your best bed is just to play with it and run the test your self.

[Parry]

You won't really loose brake power...the rears will just lock up earlier or later.

Play with it enough and you'll get the rears to lock up way before the fronts. Their different stopping power (disks vs. drums in the rear) means that if the pressures going to both was the same, the fronts would lock before the rears. Ideally, you want them all to lock up at hte same point.

You'll think having the rears lock first is pretty cool...

...until you have to panic stop on the street.

Keep your brake bias adjusted safely, and stock. If you want more stopping power convert to rear disks or invenst in some sort of braking upgrade for the drums (oxymoron? lol.). If you do upgrade the rears, it could be necesary to readjust the bias to allow for the incrased stopping power.

[ToplessFC3Sman]

I always thought that understeer when braking was due to too much rear bias, because as the rear slows down (assuming it doesnt break traction) faster than the front can, it pulls the car back to a straight-forward postion, sorta like a pendulum where the rear wheels are the pivot, and the fronts are trying to make it swing. However, with too much of a front bias, it causes oversteer cause the rear wheels arent slowing down as much as the fronts, moving faster, and then always trying to overtake the front wheels, in the form of oversteer or a spin.

breaking traction, im guessing you want to quickly jab at the brake and lock the rears (or at least slow them down substantially) to initiate the drift, essentially replacing the handbrake? I dunno, ive just gotten myself confused, so im done now.

[Emagdnim]

well I don't want the rears to lock before the fronts I just think right now the the fronts are causeing too much understeer(and I don't wanna spend $400+ for a disc conversion).

I think the reason stronger front brakes cause understeer is because decceleration takes traction, if the front is deccelerateing faster then the rear then there will be less available traction in the front. Especially while turning as that takes traction as well.

So if I messed with my bias valve I wouldn't nessicerly lose overall braking power just the power that is applied in relation to braking input. For example if I increased rear bias the rears will simply be working harder with less input and vice versa with the front. Correct? you've all been very helpful.

[nissanguy_24]

Yes, Literally by sending braking power to the rear you can dialin which wheels lock up when. Literally you will want the rears and the fronts to be perfectly balanced. locking at the same time. Basicly if i were you i would dial in alittle more rear biasing alittle at a time to see what feels the best. stopping just short of having the rears lock up first. that can be unstable

[raging panda]

when you brake while you turn, that will give you understeer in any situation really. For your braking drifts, dont give it so much brake on entry, try to go in faster than you normally would, then while into the turn already, give the brake a good jab and that should break your traction.

You only have 100 percent to give to your tires. If you are going straight a brake, 100 percent is going to be going to stopping. If you are turning and braking, that means 50 percent (just for this situation) is for turning, so when you try to give that 100 percent on your tires for braking, you will lose traction because you exceeded that 100 percent. For your understeer, if you hit the brakes before the turn too much, that means 100 percent is given to braking, and somehow you want your tires to turn when there is nothing left for them to use to turn with.

[nissanguy_24]

I have to dissagree, When i intiate a braking drift i brake before the turn. I come in really hot, then *tap tap* on the brakes, feel the weight shift forward then i turn in.. All the extra weight on the front gives me incredable grip, However the rears cant keep up, and the rear very very smoothly comes out from behind me (in the S13, your car may react differently.. but the idea is the same)

If i try to turn then apply the brake i get understeer. Kind of the same concept that makes it easier to brake traction in the rear with power when your turning.. Well it makes it easier to brake traction in the front when braking, while turning. except obviously you WANT the rears to brake traction in drifting.. not the fronts.

Anyways just some thoughts that kind of apply

[raging panda]

actually now that i think about it, you are right. Mine would end up with the car sliding outwards, not sideways. LOL. Oh well. You want all your weight on the front tires, then rotate around them. Anyways, either way, your car doesnt want more braking power in the rear, but equal braking power. If you really need more in the rear, just pull the ebrake.

[Emagdnim]

Originally posted by nissanguy_24
Basicly if i were you i would dial in alittle more rear biasing alittle at a time to see what feels the best.

thats exactly what I'm gonna do.

[Parry]

Originally posted by Emagdnim
thats exactly what I'm gonna do.

Eh....if you're adjusting for maximum stopping power then yay.

If for "driftability" then nay. Again, brakes = your life. Be smart and safe, don't compramise your own and others safety by doing anything goofy to the poor car.

Besides, I think you're trying to fix the wrong thing.

As people have said above...you can't be turning at the limits of traction in a corner, then mash the brakes and expect the car to slow down as well. Something's gotta give...the extra work of trying to stop and turn is exceeding the limits of your tires traction and you're understeering.

Soooo....either stop trying to brake in the corners ( ) or get stickier rubber. messing with your brake balance will most likely not do anything but reduce the stopping power of your car by preventing you from being able to threshold brake both the fronts and the rears simultaniously.

[Emagdnim]

I'm not trying to use the brake in corner. I'm being left with too much understeer as I begin to turn in after letting off the brakes. basicly whats happening is: I'm brakeing before the entry in order to get the weight to shift to the front, But I have to brake pretty hard in order to get the weight shift. So in the process of shifting the weight, I'm lossing alot of front end avaiable traction right as I'm about to turn in. I can't just let off the brakes and wait alittle while I get enough traction cause I'll lose the weight shift. And I'm not about to just slam on the gas while I'm feeling all kinds of understeer. So all I'm looking to do is even out my balance alittle so that I don't get understeer before the weight shifts. I'm not tryin to just turn my foot brake into an e-brake.

I appericate the concern and I will be careful.

[CrazyHawaiian]

Get the proportioning valve (or do you already have one?) and experiment. You can always re-adjust it back to best braking power under grip situations for street driving. When you're sliding the brakes react differently, and playing with the bias will give you different results. The best setting depends on your style, when you use the brakes, and what you are trying to accomplish. If you use the brakes to initiate, then of course you'd want it set differently then if you use them to correct. Just an example.

No harm in experimenting.