Stock GTspecB brakes put to the test

[gtspec]

Hey Guys

i went down to the south coast on the weekend and took the kangaroo valley route to test out the new cusco front and rear sway bars, front strut brace with brake stopper and tein flex coilovers..

i have got to say i was lucky i got no cars in my way the whole trip thru up and down the hills and had the best time and was money well spent BUTTT>>>>
the one thing that really disappointed me was the brakes.... during the downhill part of the hill i can understand the brakes struggling a bit but it was during the uphill climb that i first started to notice the brake failure..
it felt like i pressed the brake peddle but it wasnt responding so i was resorting to using gears..
but then come the downhill.. i took it easiler going down due to the way it reacted on the uphill.. but even so on the way down my steering wheel started to SHAKE rapidly whenever i touched the brakes.. so i was forced to go very very slowly down the hill in 2nd gear like a truck would.. very very disappointed with the brakes.. i know there not brembos but i would of thought they would hold up a bit better...

Anyways thats my 2 cents hehe

Cheers
Adam

[coyote]

That's not your calipers, it is your pads. Put crap pads in any caliper and that will happen.

[gtspec]

That's not your calipers, it is your pads. Put crap pads in any caliper and that will happen.

hmm could be true.. but there running stock subbie pads if that makes a difference..

and would the pads cause the steering wheel to vibrate badly when it heats up.. i felt like the calipers were warped..

[541NTT]

mines doing the same thing on occasion to- the vibrating steering wheel thing, i was testing out my brakes yesterday as well (country road doing 40klms and stamping the brakes) i was getting almost a grind coming from the front rite hand side, i think its time for me to get the brakes and allignments looked at..

[gumbyy]

would the pads cause the steering wheel to vibrate badly when it heats up.. i felt like the calipers were warped..

That happened to me on a twistie run last yr, scared the sh!t out of me I thought I broke something or fcked up the wheel alignment.. turns out something known as "brake shudder"

EDIT: But my experience was a little more extreme than yours, the steering wheel vibrated violently and there was a loud grinding noise.. It was fixed by machining the rotors.. but lately I have felt slight shuddering when braking i think its time to change the pads.

[moggy]

You'll also get some shuddering under heavy braking when the ABS kicks in...

Bob.

[sundayDriver]

my brakes shudder under braking but when I first got the car, the brakes were perfect.

my theory is that; if you go for a fang and you're using your brakes a lot, they'll heat up. then if you hit traffic or just stand on the brakes (brake pedal) the heat from the rotors will cause the pad material to bind to the rotors - causing an uneven surface -> brake shudder.

I didn't get my brakes machined, I'm thinking about a rotor and pad upgrade.

I'm also thinking of feeding a pipe from the grill next to the fog lights (MY07) to the brakes - but I'd have to take off the heat sheild to make the cooling ducts work. So i'm still sussing out what the effects would be if I took the sheilds off.

[coyote]

That's not your calipers, it is your pads. Put crap pads in any caliper and that will happen.

hmm could be true.. but there running stock subbie pads if that makes a difference..

and would the pads cause the steering wheel to vibrate badly when it heats up.. i felt like the calipers were warped..

Yep, those stock pads are crap, actually Crap (with a capital C). I took them off after 5,000km, so if anyone wants to buy a near new set of crap pads, PM me as they are sitting in the box my Ferodos came in..

Yep again, vibration is caused by your crap pads depositing material on your discs that forms little ridges. It will come off in time, so save the money you would spend on machining and get some good pads instead.

[coyote]

my brakes shudder under braking but when I first got the car, the brakes were perfect.

my theory is that; if you go for a fang and you're using your brakes a lot, they'll heat up. then if you hit traffic or just stand on the brakes (brake pedal) the heat from the rotors will cause the pad material to bind to the rotors - causing an uneven surface -> brake shudder.

I didn't get my brakes machined, I'm thinking about a rotor and pad upgrade.

I'm also thinking of feeding a pipe from the grill next to the fog lights (MY07) to the brakes - but I'd have to take off the heat sheild to make the cooling ducts work. So i'm still sussing out what the effects would be if I took the sheilds off.

I think ducting is a great idea and I've gotten great results on other cars.

If you get your brakes so hot that they fade, then stop the car and stand on the brakes, then you could have a much bigger problems than a bit of pad material on the disc. That's an ideal way to go about cracking a brake disc.

[Boxer]

Two problems,

Your pads are overheating causing the friction maerial to emit gasses that are glazing the material and disc and reducing the friction between the two (hence hard pedal and no stoppie)

and two - the stock discs are not grooved or drilled to help such gasses escape when the pads do turn to mush

Best idea is to not overheat the pads to start with and as coyote said - get decent ones first. Because an overheated pad will ultimately damage the rotors too (from experience with my old TypeR). Usually a Metal/Kevlar composite will work well, but its always a compromise between repeated stopping, cold performance and rotor wear (oh and dust emissions:))

DS2500 or DS3000 is it Tony?

Its funny how there are some people out there wanting to upgrade the Brembo's too saying they dont perform how'd theyd like on the track - but most havent addressed the street oriented pads and rotors first

[Boxer]

You'll also get some shuddering under heavy braking when the ABS kicks in...

Bob.

Yeah but at least in that situation you are actually stopping

[coyote]

DS2500 or DS3000 is it Tony?

DS2500s front and rear. I reckon DS3000s are a bit much for a road car.

[swingn]

If your getting shutter through your steering wheel under braking, it's more then likely that you've warped your discs (Been there done that ).

I really only noticed it when the brakes got nice & hot - IE Through Nasho. Otherwise, they performed fine & didn't notice a thing under normal driving conditions.

If you've got the cash available, I'd suggest you upgrade to something like Dixcel slotted rotors & a more performance based pad - Ferodo, Dixcel, Hawk etc.

It might also be worth while running some better brake fluid.

To me, the most important thing about brakes is balance... There is no point having high temp discs & pads with standard brake fluid etc etc etc.

& yes, I've learnt this the hard way... heheheheh

[gtspec]

Two problems,

Your pads are overheating causing the friction maerial to emit gasses that are glazing the material and disc and reducing the friction between the two (hence hard pedal and no stoppie)

and two - the stock discs are not grooved or drilled to help such gasses escape when the pads do turn to mush

Best idea is to not overheat the pads to start with and as coyote said - get decent ones first. Because an overheated pad will ultimately damage the rotors too (from experience with my old TypeR). Usually a Metal/Kevlar composite will work well, but its always a compromise between repeated stopping, cold performance and rotor wear (oh and dust emissions:))

DS2500 or DS3000 is it Tony?

Its funny how there are some people out there wanting to upgrade the Brembo's too saying they dont perform how'd theyd like on the track - but most havent addressed the street oriented pads and rotors first

that makes sense, thanks for the explaination, go the TypeR, i use to have one too

DS2500 is the pads i take it? sorry for the ignorance, not familiar with brakes.. and what they worth?

[gtspec]

If your getting shutter through your steering wheel under braking, it's more then likely that you've warped your discs (Been there done that ).

I really only noticed it when the brakes got nice & hot - IE Through Nasho. Otherwise, they performed fine & didn't notice a thing under normal driving conditions.

If you've got the cash available, I'd suggest you upgrade to something like Dixcel slotted rotors & a more performance based pad - Ferodo, Dixcel, Hawk etc.

It might also be worth while running some better brake fluid.

To me, the most important thing about brakes is balance... There is no point having high temp discs & pads with standard brake fluid etc etc etc.

& yes, I've learnt this the hard way... heheheheh

yeh the shuttering went away thou after about 30mins of relaxed driving.. i thought it was permanent but i guess it unwarped itself lol but i guess it would come back when it gets nice n hot again like u said..

yeh im 100% wanting to upgrade but the amount of cash i have on the side is limited..

what you reckon are the most effective without breaking the budget..
pads and fluid?