ALFAGTV6.COM

matt · Post by **matt** » Mon Jun 20, 2005 12:01 am

Hi everyone I'm wondering with so many front brake upgrade options out there, Wilwood Dynalite calipers + Supra rotors
Brembo 951 calipers + Coleman rotors
Mazda RX-7 F3CS calipers + Supra rotors
Movit DE kit
GTA Brembo calipers + BMW rotors
Volvo 4-pot calipers + stock rotors
Praggia calipers + GTA rotors
etc
with increased front rotor diameter and increased front caliper piston diameter(s) whats everyone doing to offset this increase in front brake bias. This means front brakes can lock up way before the rears come even close therefore the overall braking ability of the car is not optimum or even reduced? right?
So to get the front rear bias back to stock, optimum whats everyone doing???
Adjustable bias valve on front brake line maybe(dosent right to me?), or better rear pads??I dunno.
Or with improved front brakes and therfore greater weight transfer to the front under braking is this bias cancelled out because of less weight on the rear tyres????????? and therefore no problem

Micke · Post by **Micke** » Mon Jun 20, 2005 2:30 am

Many people are just happy having BIG BRAKES

To utilize the braking power, tuning is needed.
In case rear brakes stay stock, exchanging the OE rear brake pressure regulator with an adjustable is the easy way to go.

joey · Post by **joey** » Mon Jun 20, 2005 3:38 am

yep, that really pisses me off too, all the upgrade kits are front only...

i havent thought about it much, but i've toyed with the idea of wilwoods up front on nissan discs.. either altima/maxima or perhaps n/a skyline.. at the rear you could fit outboard front gtv6 discs??

the nissans are around 280-289 at the front, so that would match the stock rotor proportions frnt/rear... pads is another issue tho...

it would be good if someone has fitted oem calipers off another newer car to match and retain handbrake, never heard of one yet.. oh well, never too late to be a pioneer eh?

of course building a track weapon is much simpler, as you could simply fit the same calipers all round and then fine tune for rear wheel lock up..

or stick with stock calipers on matching but bigger rotors...

but in general comparing one person's BB kit to another is quite pointless, b/c i think a lot depends on suspension... ie, someone's modest frnt upgrade could work okay if they have fairly soft suspension... on the other hand a stiff set up would increase the threshold for more braking contribution from the rear and so on.

rz · Post by rz » Mon Jun 20, 2005 4:57 am

a rear upgrade doesn't help much but costs a lot!
u can put an oilcooler on your gearbox to keep the disks cooler!like on my rz.the gearbox gets hot and so it heats up the disks unnecessarely.

Micke · Post by **Micke** » Mon Jun 20, 2005 5:09 am

Heh, it was a joke - right!

An oil cooler for the sake of the rear brakes

The gearbox doesn't (hopefully) get hot enough to be in the operating temperature for brake pads..

Mats · Post by **Mats** » Mon Jun 20, 2005 5:37 am

I see 130* on my trans-oil-meter regularly. Nowhere near the brake temp but not very good for the oil either...

Putting sticky rubber on the car and braking hard really moves the (available) braking forces forward and the rear setup is quite effective, just add some cooling.

rz · Post by rz » Mon Jun 20, 2005 5:37 am

alfa romeo puts oilcoolers on sz and rz for keeping the brakes cool!!this is not a joke!

rz · Post by rz » Mon Jun 20, 2005 5:37 am

oilcoolers on the gearbox i mean!

Mats · Post by **Mats** » Mon Jun 20, 2005 6:41 am

Where have you heard this? Why would the ES30 need additional cooling, it already has vented rotors...

More likely they need to cool the GB oil, hence the GB oil cooler.
I can honestly not find a more expensive solution to cool the brakes then to fit an oil cooler, surely you can't mean that the engineers are that stupid?

rz · Post by rz » Mon Jun 20, 2005 7:00 am

the es30 has the imsa setup originally.
some very well mechanic (?) told me the oilcooler was for cooling the whole unit,brakes gearbox.

joey · Post by **joey** » Mon Jun 20, 2005 7:51 am

rz wrote:a rear upgrade doesn't help much but costs a lot!
u can put an oilcooler on your gearbox to keep the disks cooler!like on my rz.the gearbox gets hot and so it heats up the disks unnecessarely.

well, i'm anal i s'pose.. i dont like the inboard setup much, and for some reason i never got on well with the rear calipers.

Maurizio · Post by **Maurizio** » Mon Jun 20, 2005 9:12 am

I think the story of the SZ should be, that the brakes heat up the gearbox(\oil) too much.

MerrilGordon · Post by **MerrilGordon** » Mon Jun 20, 2005 11:07 am

I'd say adjustable brake bias is in the cards.
With the stock configuration on my early GTV6, the front and rears lock up at the same time. With gummy track tires the rears would be locking up too soon.

I'll be converting to vented rotors on the rear one of these days and wonder if pad wear will decrease due to (hopefully) cooler temperatures. I'm thinking that if pad wear isn't reduced (those pads are pretty small) then I'll need to bias more work load to the front. At the moment I'm going through a set of carbon metalic pads at one track day. Changing the bias might be at the expense of brakeing distances but would ease up on the stress to the rear brakes enough to make them last.

Merril

Mats · Post by **Mats** » Mon Jun 20, 2005 12:29 pm

buy harder rear pads...

Micke · Post by **Micke** » Mon Jun 20, 2005 12:42 pm

"some very well mechanic"

I know this kind of mechanics too. Time to change 'em.

Front/Rear brake bias