14" 4 piston F50 brakes...who sells them??
#16
Race Director
Thread Starter
Sterling
Nope.....I ended up buying the track shark which already has GTS brakes a couple months after this post & sold Sharky..... At the current HP level the widow has, the GTS brakes keep up just fine....feel VERY powerful....I've had passenger-instructors that comment on how powerful the brakes are with pagid orange pads & I think I have a 33 bias bar...I can defintely feel the rears are doing more braking than in my stock 928.....since even a bit of trail braking really gets the tail to come around!! :>)
When I upgrade the HP in the widow I will upgrade the brakes.....but the raceshop has some connections at Wilwood and can get me a great deal....so I might try those.....but its still at least a year away
Nope.....I ended up buying the track shark which already has GTS brakes a couple months after this post & sold Sharky..... At the current HP level the widow has, the GTS brakes keep up just fine....feel VERY powerful....I've had passenger-instructors that comment on how powerful the brakes are with pagid orange pads & I think I have a 33 bias bar...I can defintely feel the rears are doing more braking than in my stock 928.....since even a bit of trail braking really gets the tail to come around!! :>)
When I upgrade the HP in the widow I will upgrade the brakes.....but the raceshop has some connections at Wilwood and can get me a great deal....so I might try those.....but its still at least a year away
Last edited by IcemanG17; 09-03-2009 at 12:13 AM. Reason: spilling
#17
Nordschleife Master
I am still planning on putting a set of 380mm rotors on the front of my car, and in turn upgrading the rears to S4 fronts.
I will be running an adjustable bias valve to dial in the backs for dry and wet.
I will be running an adjustable bias valve to dial in the backs for dry and wet.
#18
Race Director
Thread Starter
Kibort runs a 355mm rotor with stock S4 calipers-pads using a simple spacer? by far the most cost effective solution.....I would imagine a similar spacer would work with GTS calipers too
#19
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I wouldn't call it a simple spacer - if he has it set up the way I was thinking.
It would require the caliper bolt seating surface to be stepped in along with the caliper itself. The spacer would also need to be turned wider in the center and the ends would need to fit into the caliper and spindle like a hub centric wheel does.
The way I'm explaining this makes no sense....
The spacer would need to FIT into the caliper and spindle. If it didn't the caliper would move under force.
It would require the caliper bolt seating surface to be stepped in along with the caliper itself. The spacer would also need to be turned wider in the center and the ends would need to fit into the caliper and spindle like a hub centric wheel does.
The way I'm explaining this makes no sense....
The spacer would need to FIT into the caliper and spindle. If it didn't the caliper would move under force.
#21
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Here is a picture of a performance motorcycle caliper. See how the spacer is stepped? I thought of doing this to my 928 calipers to run larger rotors.
How do yo like those vented titanium pistons? hehehe...
How do yo like those vented titanium pistons? hehehe...
#23
Rennlist Member
As we discussed, why would anyone really want to do this,when it is very simple to use offset washers and use a 322mm rotor with the stock S4 calipers and pads. there really is no advantage of extra surface area on the inner diameter as the pads are near the same arc width, not radius depth. If you look at any race car, they have near the same size pads as the 928S4, but out on the radius more.
Big change will be to a real race pad, like the pagid black RS14 or Hawk HT14.
the huge calipers are really not that big of a need for race cars with proper cooling. again, the Stoptech full race set up for most all the race cars out there use the exact same pad as we do, and those cars run faster than any 928 that has hit the track besides joe and mark A.
mk
Big change will be to a real race pad, like the pagid black RS14 or Hawk HT14.
the huge calipers are really not that big of a need for race cars with proper cooling. again, the Stoptech full race set up for most all the race cars out there use the exact same pad as we do, and those cars run faster than any 928 that has hit the track besides joe and mark A.
mk
Your stock f.brakes are actually 304mm.
The upgrade to GTS big black/red gains you an upsized rotor to 322mm and a larger caliper body but not any caliper piston difference. The resultant larger caliper then takes a larger pad with a total net gain of 50cm squared.
If you've yet to fade the stockers on track I'd suggest you play with the pad material then perhaps upsize to GTS as the $$$ are reasonable.
No idea price or availability of F50s but they sound mega $$$.
The upgrade to GTS big black/red gains you an upsized rotor to 322mm and a larger caliper body but not any caliper piston difference. The resultant larger caliper then takes a larger pad with a total net gain of 50cm squared.
If you've yet to fade the stockers on track I'd suggest you play with the pad material then perhaps upsize to GTS as the $$$ are reasonable.
No idea price or availability of F50s but they sound mega $$$.
#24
Rennlist Member
I dont follow.
Its just a simple spacer. it moves the caliper out just under .5" and allows for use of the 322mm rotors. If brian wanted to run 350s, he would need a rotor that was the same offset as the GTS rotors and I dont know of any larger diameters that fit that spec. certainly, the answer would be to use a hat set up and then he could just space out the GTS calipers 1" and be ready to go with big calipers and huge 14" rotors.
Here is the picture of the spacer I use, along with the comparison to the stock S4 rotor and the machining area needed to be dremmeled out on the S4 caliper:
Its just a simple spacer. it moves the caliper out just under .5" and allows for use of the 322mm rotors. If brian wanted to run 350s, he would need a rotor that was the same offset as the GTS rotors and I dont know of any larger diameters that fit that spec. certainly, the answer would be to use a hat set up and then he could just space out the GTS calipers 1" and be ready to go with big calipers and huge 14" rotors.
Here is the picture of the spacer I use, along with the comparison to the stock S4 rotor and the machining area needed to be dremmeled out on the S4 caliper:
I wouldn't call it a simple spacer - if he has it set up the way I was thinking.
It would require the caliper bolt seating surface to be stepped in along with the caliper itself. The spacer would also need to be turned wider in the center and the ends would need to fit into the caliper and spindle like a hub centric wheel does.
The way I'm explaining this makes no sense....
The spacer would need to FIT into the caliper and spindle. If it didn't the caliper would move under force.
It would require the caliper bolt seating surface to be stepped in along with the caliper itself. The spacer would also need to be turned wider in the center and the ends would need to fit into the caliper and spindle like a hub centric wheel does.
The way I'm explaining this makes no sense....
The spacer would need to FIT into the caliper and spindle. If it didn't the caliper would move under force.
#25
Nordschleife Master
Hey MK,
I am afraid that you really failed on this post
Malcolm posted that 06-14-2008. WELL before you did your brake mods/upgrade.
I am afraid that you really failed on this post
Malcolm posted that 06-14-2008. WELL before you did your brake mods/upgrade.
As we discussed, why would anyone really want to do this,when it is very simple to use offset washers and use a 322mm rotor with the stock S4 calipers and pads. there really is no advantage of extra surface area on the inner diameter as the pads are near the same arc width, not radius depth. If you look at any race car, they have near the same size pads as the 928S4, but out on the radius more.
Big change will be to a real race pad, like the pagid black RS14 or Hawk HT14.
the huge calipers are really not that big of a need for race cars with proper cooling. again, the Stoptech full race set up for most all the race cars out there use the exact same pad as we do, and those cars run faster than any 928 that has hit the track besides joe and mark A.
mk
Big change will be to a real race pad, like the pagid black RS14 or Hawk HT14.
the huge calipers are really not that big of a need for race cars with proper cooling. again, the Stoptech full race set up for most all the race cars out there use the exact same pad as we do, and those cars run faster than any 928 that has hit the track besides joe and mark A.
mk
#26
Rennlist Member
Failed? How so. Im not bucking for credit here, just posting results.
If Malcolm posted this back in the day, where is the post?
anyway, I have the exact specs needed to make the mod work. (if anyone needs it )
mk
If Malcolm posted this back in the day, where is the post?
anyway, I have the exact specs needed to make the mod work. (if anyone needs it )
mk
#27
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Mark,
Is there any free play between the caliper holes and the caliper bolts before it's tightened? If so I would recommend putting a step on the spacer that goes into the caliper and spindle, like in the pic I posted. This is to keep the caliper from moving when radially mounted. I once spaced a caliper using only a 5mm shim and the caliper loosened up on Palomar mountain, after being torqued to correct specs and loctite. Just my .0002 cents
Is there any free play between the caliper holes and the caliper bolts before it's tightened? If so I would recommend putting a step on the spacer that goes into the caliper and spindle, like in the pic I posted. This is to keep the caliper from moving when radially mounted. I once spaced a caliper using only a 5mm shim and the caliper loosened up on Palomar mountain, after being torqued to correct specs and loctite. Just my .0002 cents