951 GTP Kits & More!!!
12-14-2004, 05:41 PM
#16
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Will the "Porsche" name come on the calipers or "Brembo"?
Can the stock rear 951 calipers/rotors keep up with a front only GTP setup, like with a typical "Big Red" upgrade? Or would the stock front setup moved to the rear be a better match with the GTP setup?
What will the bias valve requirements be on
1. front GTP only (stock 951rear/951 front moved to rear)
2. front & rear GTP setup.
What brake pads are recomended for street use? track use?
Is there a price difference between the GTP-LW and the GTP? Is the price offered for the GTP-LW or GTP?
Please expand on the differences between the GTP-LW and the GTP. From your discription the rotor diameter is the same, only diff is the LW uses Brembo rotors and the GTP uses Porsche. What is the replacement price differences for the two rotors (future maintenance). Is the larger rim requirement due to a larger caliper on the GTP?
You also alude to a difference in the way the GTP's apply clamping force. Will this be an issue on non-ABS 86 cars? Say a panic stop from 175mph.
(just kidding, panic stop @ 175 and you are in serious trouble)
Can the stock rear 951 calipers/rotors keep up with a front only GTP setup, like with a typical "Big Red" upgrade? Or would the stock front setup moved to the rear be a better match with the GTP setup?
What will the bias valve requirements be on
1. front GTP only (stock 951rear/951 front moved to rear)
2. front & rear GTP setup.
What brake pads are recomended for street use? track use?
Is there a price difference between the GTP-LW and the GTP? Is the price offered for the GTP-LW or GTP?
Please expand on the differences between the GTP-LW and the GTP. From your discription the rotor diameter is the same, only diff is the LW uses Brembo rotors and the GTP uses Porsche. What is the replacement price differences for the two rotors (future maintenance). Is the larger rim requirement due to a larger caliper on the GTP?
You also alude to a difference in the way the GTP's apply clamping force. Will this be an issue on non-ABS 86 cars? Say a panic stop from 175mph.
(just kidding, panic stop @ 175 and you are in serious trouble)
Last edited by Bill; 12-14-2004 at 06:18 PM.
12-14-2004, 06:59 PM
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Paul,
First, I want them for my '86 turbo front. I will move current stock fronts to rear. Any changes required to make this switch? Stock brake bias okay. Finally, how long are we talking assuming you get enough orders? I have races starting in February. Also need race seats on sliders for my car. Thanks. Andy.
First, I want them for my '86 turbo front. I will move current stock fronts to rear. Any changes required to make this switch? Stock brake bias okay. Finally, how long are we talking assuming you get enough orders? I have races starting in February. Also need race seats on sliders for my car. Thanks. Andy.
12-14-2004, 07:01 PM
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Well you can certainly put me down as interested; if I could get some sort of Brembo / multi piston setup for the early car I'd be thrilled. Supposedly the stock brakes are fine, but this is for a highly modded car and I'd rather not deal with the hassle of swapping later-model axles into it and having a mishmash of different year pieces on it to keep track of! Thanks.
12-14-2004, 07:12 PM
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How is 1950.00 front, and 1850.00 rear better than 3600.00+, when bought separately? no offense intended, just...uhhh....that's 200.00 more?
12-14-2004, 08:05 PM
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No Porsche Logo.... It will same Brembo.
Obviously a front and rear GTP setup would be the best way to go if money were no object......However, you can keep the stock rear calipers just like the BR kits but you may have to play with the bias a little........plus 60-70% of the breaking is done up front so the real hard breaking will be done by the GTP!
Also the big and open ended question is..... what type of car are you running? Stock, modified or race? Also What is your driving style and braking demands. How much does your car weigh and what tires and suspension set up do you have! All factors that need to be considered.... especially when dealing with something as important as breaks!
Keeping the stock rears......I would say you will have to dial out some bias thru the use of a larger rotor in the rear and a higher friction pad. Or for those of you who wish to have more control.... a bias valve. I believe Porsche factory bias valves come in 3 or 4 settings. Or an after market bias valve.
As with the Big Reds the GTP pads are very substantial for street use and reasonable for auto-X or light track. Brembo are good at making a good compromise pad!
The best pads I have ever seen and tested (and I have tested them all) are the Performance Friction pads.... we stock and sell these. The 93 compound seems to be the best one.... great modulation, rotor friendly, and MASSIVE Stopping power! A little noise but nothing major! If you need this type of pad ( I.e. very aggressive track or racing), a little noise is all part of the game!
Plus the 2 most important things I noticed with the performance friction pads.... 1. they don’t heat bleed on to the rotors (this causes resin from the pad to burn out on to the rotor and cause a nasty rumble on braking and you loose performance) The other great thing is these pads last 2 or 3 times longer than say a Padgid! So you get great value for the money!
So if the Brembo Pads are not as aggressive as you need... then my recommendation is the Performance Friction! But it all come down to personal preference and each person driving style!
Ok the major differences in the GTP and the GTP-LW:
1. Size.... the GTP-LW can fit under a 16inch and the GTP needs a 17 inch
2. Caliper and pad size.... same reason as point one
3. The GTP Front calipers use 40mm & 44mm pistons and the rears have 28mm & 30mm pistons ------ the GTP-LW uses Brembo 4 Piston Calipers use sequential Pistons (36mm-40mm Front and Rear) the calipers are the same front and rear in the GTP-LW kits.
4. The GTP kit comes with only a rear park break option... the GTP-LW kits have 2 options:
Rear – 1 Piece Porsche Cross-Drilled and Vented 12" (304mm) disc with full parking brake capability
Or
Rear – 2 Piece Brembo racing vented and cross-drilled or slotted rotors with lightweight, floating, hats. This option is for the enthusiast who values weight savings and does not allow for the stock parking brake.
The GTP kits cost more..... and to be honest! for a car close to 3000lbs or less the GTP-LW kit has more stopping power then you will ever need!
In talking to brembo the full GTP kit is derived from Large Grand-Am cars like Vetts or mustangs. Thus the reason why its bigger!
The GTP-LW is more towards your Porsche, BMW vane of cars. Remember larger is heavier and more unsprung weight!
To address you Q about the way the GTP's apply clamping force..... please see my earlier passage from Brembo>>>>
The Brembo calipers are both lighter and offer higher rigidity than Big Reds, the decreased weight means better handling through decreased unsprung mass while the increased rigidity allows both higher clamping force and incredibly consistent pedal response.
The GTP-LW kit is 20 years younger in design then is BR older sibling...... the new design out performs the BR's in every way.
Pedal feel and response / Modulation is excellent on the GTP-LW's.
Non ABS cars all have the potential to lock up. Again this is an open ended question!..... who is driving, how does the person drive and how competent is the driver, Road Conditions, Car set up etc.......... Simple answer, don’t stamp em a a buck 75 LOL (Just kidding) There is certainly more stopping power than stock but is all about pedal feel and modulation. My real answer to this is Brembo know what they are doing and would not be offering such a kit if weird characteristics, such as lock up, we any major concern on the 86 non-ABS cars. I have an 86 and I do hit 175... so I will let you know soon when I throw on a set LOL
Ehall..... that was $3600 for the front and the same for the rear! So there is a LOT of $$$ saving! About 50% or close to it!
Time Wise.... I am still finding out a firm ETD from Brembo.
I hope this helps answer some of your q's.........
Cheers,
Paul R
Obviously a front and rear GTP setup would be the best way to go if money were no object......However, you can keep the stock rear calipers just like the BR kits but you may have to play with the bias a little........plus 60-70% of the breaking is done up front so the real hard breaking will be done by the GTP!
Also the big and open ended question is..... what type of car are you running? Stock, modified or race? Also What is your driving style and braking demands. How much does your car weigh and what tires and suspension set up do you have! All factors that need to be considered.... especially when dealing with something as important as breaks!
Keeping the stock rears......I would say you will have to dial out some bias thru the use of a larger rotor in the rear and a higher friction pad. Or for those of you who wish to have more control.... a bias valve. I believe Porsche factory bias valves come in 3 or 4 settings. Or an after market bias valve.
As with the Big Reds the GTP pads are very substantial for street use and reasonable for auto-X or light track. Brembo are good at making a good compromise pad!
The best pads I have ever seen and tested (and I have tested them all) are the Performance Friction pads.... we stock and sell these. The 93 compound seems to be the best one.... great modulation, rotor friendly, and MASSIVE Stopping power! A little noise but nothing major! If you need this type of pad ( I.e. very aggressive track or racing), a little noise is all part of the game!
Plus the 2 most important things I noticed with the performance friction pads.... 1. they don’t heat bleed on to the rotors (this causes resin from the pad to burn out on to the rotor and cause a nasty rumble on braking and you loose performance) The other great thing is these pads last 2 or 3 times longer than say a Padgid! So you get great value for the money!
So if the Brembo Pads are not as aggressive as you need... then my recommendation is the Performance Friction! But it all come down to personal preference and each person driving style!
Ok the major differences in the GTP and the GTP-LW:
1. Size.... the GTP-LW can fit under a 16inch and the GTP needs a 17 inch
2. Caliper and pad size.... same reason as point one
3. The GTP Front calipers use 40mm & 44mm pistons and the rears have 28mm & 30mm pistons ------ the GTP-LW uses Brembo 4 Piston Calipers use sequential Pistons (36mm-40mm Front and Rear) the calipers are the same front and rear in the GTP-LW kits.
4. The GTP kit comes with only a rear park break option... the GTP-LW kits have 2 options:
Rear – 1 Piece Porsche Cross-Drilled and Vented 12" (304mm) disc with full parking brake capability
Or
Rear – 2 Piece Brembo racing vented and cross-drilled or slotted rotors with lightweight, floating, hats. This option is for the enthusiast who values weight savings and does not allow for the stock parking brake.
The GTP kits cost more..... and to be honest! for a car close to 3000lbs or less the GTP-LW kit has more stopping power then you will ever need!
In talking to brembo the full GTP kit is derived from Large Grand-Am cars like Vetts or mustangs. Thus the reason why its bigger!
The GTP-LW is more towards your Porsche, BMW vane of cars. Remember larger is heavier and more unsprung weight!
To address you Q about the way the GTP's apply clamping force..... please see my earlier passage from Brembo>>>>
The Brembo calipers are both lighter and offer higher rigidity than Big Reds, the decreased weight means better handling through decreased unsprung mass while the increased rigidity allows both higher clamping force and incredibly consistent pedal response.
The GTP-LW kit is 20 years younger in design then is BR older sibling...... the new design out performs the BR's in every way.
Pedal feel and response / Modulation is excellent on the GTP-LW's.
Non ABS cars all have the potential to lock up. Again this is an open ended question!..... who is driving, how does the person drive and how competent is the driver, Road Conditions, Car set up etc.......... Simple answer, don’t stamp em a a buck 75 LOL (Just kidding) There is certainly more stopping power than stock but is all about pedal feel and modulation. My real answer to this is Brembo know what they are doing and would not be offering such a kit if weird characteristics, such as lock up, we any major concern on the 86 non-ABS cars. I have an 86 and I do hit 175... so I will let you know soon when I throw on a set LOL
Ehall..... that was $3600 for the front and the same for the rear! So there is a LOT of $$$ saving! About 50% or close to it!
Time Wise.... I am still finding out a firm ETD from Brembo.
I hope this helps answer some of your q's.........
Cheers,
Paul R
12-14-2004, 08:50 PM
#23
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Any plans to do repeated 60-0 or 100-0 tests to compare BR to GTP brakes? There is a big difference in the price and such data should be essential. Of course the tests should be done under the same conditions (same car, same tires, same tire pressure, close enough outside & surface temp, and same pad material). I use the 951S on my MY89 951 race car, if I can see concrete data proving that the new brakes are worth the extra $$$ (double the cost of BR for me as I have Turbo S spindles), I'm in for a set.
12-14-2004, 11:56 PM
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Originally Posted by fast951
Any plans to do repeated 60-0 or 100-0 tests to compare BR to GTP brakes? There is a big difference in the price and such data should be essential. Of course the tests should be done under the same conditions (same car, same tires, same tire pressure, close enough outside & surface temp, and same pad material). I use the 951S on my MY89 951 race car, if I can see concrete data proving that the new brakes are worth the extra $$$ (double the cost of BR for me as I have Turbo S spindles), I'm in for a set.
Let me know if you need a test car.
12-16-2004, 12:02 AM
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Paul, I think we were all looking for actual road test numbers. Looking at the facts regarding the brake specifications helps, but it does not make us want to spendsignificantly more money unless it really makes a HUGE difference. The 951S brakes are enough for these cars, the BIG REDS are just ridiculous and almost unnecessary. Without abs, is it even safe to run these GTP calipers?
12-16-2004, 02:23 AM
#28
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Guys please don't flame me here but exactly what is the difference between the Big Reds and the stock Turbo S ( S4 ) brakes ? i.e. Unsprung weight, pistions sizes and over all stopping power ?
TIA
Ed
TIA
Ed
12-16-2004, 04:09 AM
#29
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Big Reds use larger brake disc, 322mm ( 12,7" ) vs. 302mm ( 11,9" ),pads and pistons are of same size.-EDITED-
That larger disc brings more stopping power because of more torque arm.
So you can use either 928 S4 or TurboS calipers on a 951 with certain 16" wheels,but you can't use 322mm discs( and BR calipers ) without 17" wheels. Or have't been able until this GTP kit.
That larger disc brings more stopping power because of more torque arm.
So you can use either 928 S4 or TurboS calipers on a 951 with certain 16" wheels,but you can't use 322mm discs( and BR calipers ) without 17" wheels. Or have't been able until this GTP kit.
Last edited by pete95zhn; 12-16-2004 at 12:06 PM.
12-16-2004, 05:11 AM
#30
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Paul,
I love the informational night idea. Keep us Posted!
Also did you mention something about an exhaust you might be producing? I would be very interested in that. I'd love to see another company produce some nice boost pipes cheaper then what alot of the other guys have. It seems they could be made much more reasonably...
Zack
I love the informational night idea. Keep us Posted!
Also did you mention something about an exhaust you might be producing? I would be very interested in that. I'd love to see another company produce some nice boost pipes cheaper then what alot of the other guys have. It seems they could be made much more reasonably...
Zack