bwzabodyn

iTrader: (2)

Hey guys,

I'm a G35 Coupe 5AT owner, and I'm trying to get most of the benefits of a BBK without the high price tag... here's what I'm shooting for:

I'm going to try to purchase a set of Brembo calipers/hardware from a salvage yard from a wrecked Z and buy SS lines and Stoptech Rotors separately (what will be around a $700 investment) - my question for all the brake experts: will this setup throw off the brake bias too much if I keep the stock rear brakes (I'll be upgrading the lines/fluid/pads as well)? Is it absolutely necessary to upgrade the rear brakes as well (even though I'll do it eventually - I just found a great deal on the front calipers only)...

Any input on this subject is greatly appreciated!

ZPirate

It may throw off the bias front to rear since the front Brembos are designed to work with the rear Brembo calipers. Why not go ahead and get the rear Brembos too? Then you have the whole kit. Even if it cost you another$700, $1,400 would be great for a complete 4 wheel kit, about the same cost as a front BBK. That is one good thing about a BBK like StopTechs, the front kit works with the stock master cylinder and doesn't mess up the bias front to rear.

bwzabodyn

iTrader: (2)

Thanks for the info - I would do the whole thing at once, but the problem is finding a rear set at a reasonable price (I've found a set of calipers/rotors for $600 - EACH CORNER!) - if I could find a set of rear calipers for the same price I'm paying for the fronts, then it would be a no brainer... but I think for the time being, I'm going to do the front, and upgrade as I go...

E K

iTrader: (10)

I ran with just front Brembos for awhile, and the car was fine. The Track Brembos with Stoptech 2 piece rotors is a great setup.

Check on ebay for the rears. I got my rear brembo calipers new for $500 for the pair.

ZPirate

You will probably be alright with just the front kit. Worse case your rear pads may wear out sooner. Still your front brakes will likely do 90% plus of the work.

nismo33

iTrader: (15)

does anyone know if the track model use a different master cylinder

ZPirate

I don't believe the master cylinder was any different for 03, but it seems like a read that the master cylinder for the Track model changed in 04 so that it was different from the non Track models. I think the new one is a tandem master cylinder. I will see if I can find anything on it.

ZPirate

Found this from an earlier thread. Still looking for more info.


"As far as I've been able to research (using online Nissan parts catalogs), here are the differences:

There are two master cylinders available, 1). for the Base Model, 2). for all other models.

There are three different brake boosters; 1).for the Base model, 2). for the Track model, 3)for all other models."

bwzabodyn

iTrader: (2)

wonder what the difference is with G35 coupes (since there's really just 5AT's and 6MT's)?

J Ritt

iTrader: (4)

First...master cylinder is not an issue on these cars. There are some minor changes to the design through the model years, but no functional difference whatsoever. So, there are no compatability issues.

As for using the front Brembo's only...here's what you're looking at:

The front Track Brembo's are designed to work with the specific rotor diameters found on the Track Model...front and rear...and with the rear Brembo caliper.
All else held equal, any change to one of these three things will alter the amount of brake torque on the end of the car you are manipulating:
1. Rotor diameter
2. Piston bore change
3. Coefficient of friction of the pad

Now I haven't consulted my engineers, but I'm fairly certain that the total area of the 4 piston bores on each of the front Track Model Brembos is larger than the area of the single piston slider caliper found on the front stock base model 350Z brakes. So, all else held equal...if you put the front Brembos on the front of your Z that was originally equipped with base brakes, you are altering point #2 in the list above with everything else the same. Since you are increasing the average piston bore size, you are increasing the amount of brake torque on the front axle, and you are shifting brake bias to the front of the car. Additionally, you can't add the Brembo's to the base model rotors. So, you are changing point #1 above as well. As the rotor diameter grows, the amount of brake torque generated on the front axle grows, and the bias shifts even further to the front.

So what does that mean? That means that your rear brakes are no longer doing their intended share of the total work. My guess is that if you did some stops in front of a radar gun, you'd see that your stopping distances actually increased with this setup. Essentially, you aren't using all of the resource of your rear tires, and they're along for the ride.
Front bias is a stable condition though, so it shouldn't be dangerous in terms of balance. The front brakes will lock up first, and the car will be stable. If you were to shift bias too much bias to the rear though, you would run the risk of locking the rears first, and causing a spin.

The next logical question is, "well how is it that StopTech can put a front BBK on a car and keep the stock rears?" Here's why: The point of the BBK is to increase heat capacity through the use of a large rotor...it's a big heat sink that flows more air due to superior internal vane design. When we put a big rotor on the front of the car, we are potentially shifting bias to the front of the car, as we were in the example above. Now, here's the biggest point of differentiation between StopTech kits and all of our competition...StopTech sizes the pistons in the caliper specifically for each application, so we can properly counteract the increase in torque output caused by the use of the larger diameter rotor. In other words, we put the big rotor on for more heat capacity, but we use smaller diameter pistons to bring the brake torque down into the proper range. Most of our competitors use calipers out of their parts bin with a set piston bore. Therefore, they aren't dialing the kit in properly from the start, and the only option they have to alter front to rear balance is rotor diameter or friction changes. That's why you can use one of our front kits, and it's perfectly balanced with the stock rear. If you want to add our 2 piston rear kit later, you can. All we do is mimic the torque output of the stock rear setup using our components. As a side bonus, pedal travel on our kits is usually shorter because with smaller pistons, you aren’t displacing as much fluid to make them a given distance.

Let me know if this doesn't make sense!

Lawn Dart

iTrader: (4)

Master Cylinder type one is for the Base and Enthusiast model. Type two is for all others. The difference? VDC.