Review: Cobalt Friction GT-R Spec.VR
09-03-2003, 10:19 AM
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Review: Cobalt Friction GT-R Spec.VR
I ran my 350Z with Cobalt's GT-R Spec.VR at Gingerman and here are my thoughts (ymmv, of course). 1.9 mile road course with slight elevation changes, supposedly a horsepower track moderate to hard on brakes.
Car specs, 350Z Track w/ ATE Super Blue, no brake ducting, street tires. GT-R Spec.VR in front and GT-Sport in back. Covered ~240 track miles this past track event, no sessions.
GT-R Spec.VR have good initial bite with a very linear pedal feel, pedal pressure = stopping power which I think allows for easy brake modulation. The amount of torque these pads can exert is great. These pads don't produce much brake dust at all, which completely surprised me for full race pads. These pads have a very high fade critical temp. rating, I could feel the ATE fluid begin to boil. Improve one part and you can start to see the weaknesses of other parts. Bottom line, I need brake ducting.
When I switched back to street pads I inspected my brakes and this is what I found. The rotors looked healthy, still had plenty of life to them. The GT-Rs pad material that was transferred to the rotors leaves a slightly blue tint, but absolutely no scoring. The pads themselves didn't look very worn out. I didn't measure before and after but they look like they'll last me in well in to next year (~1 track event a month, usually don't run sessions).
Personally, GT-Sports will be sufficient as soon as I get ducting. I prefer their initial bite over the GT-Rs. Also, I don't think my wheel bearings/internals will last very long with pad temps over 1000F (the fade critical temp of GT-Sports). My preference for GT-Sports may change if I add R-compounds or BFG KDWs.
One thing I don't like about GT-Sports is their incessant squealing.
I have no affiliation with Cobalt Friction.
Car specs, 350Z Track w/ ATE Super Blue, no brake ducting, street tires. GT-R Spec.VR in front and GT-Sport in back. Covered ~240 track miles this past track event, no sessions.
GT-R Spec.VR have good initial bite with a very linear pedal feel, pedal pressure = stopping power which I think allows for easy brake modulation. The amount of torque these pads can exert is great. These pads don't produce much brake dust at all, which completely surprised me for full race pads. These pads have a very high fade critical temp. rating, I could feel the ATE fluid begin to boil. Improve one part and you can start to see the weaknesses of other parts. Bottom line, I need brake ducting.
When I switched back to street pads I inspected my brakes and this is what I found. The rotors looked healthy, still had plenty of life to them. The GT-Rs pad material that was transferred to the rotors leaves a slightly blue tint, but absolutely no scoring. The pads themselves didn't look very worn out. I didn't measure before and after but they look like they'll last me in well in to next year (~1 track event a month, usually don't run sessions).
Personally, GT-Sports will be sufficient as soon as I get ducting. I prefer their initial bite over the GT-Rs. Also, I don't think my wheel bearings/internals will last very long with pad temps over 1000F (the fade critical temp of GT-Sports). My preference for GT-Sports may change if I add R-compounds or BFG KDWs.
One thing I don't like about GT-Sports is their incessant squealing.
I have no affiliation with Cobalt Friction.
09-03-2003, 10:33 AM
#2
Did you really have to heat up the pads to benefit from their bite? I've already over-cooked my GT-S' on every weekend that I've used them, and I could use a pad with a higher fade critical temp. My only concern is how much heat you have to build up in the pads before you can maximize it's coefficient of friction.
Great review nonetheless!
Great review nonetheless!
09-03-2003, 04:17 PM
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John,
first time out I took it easy. I didn't have a proper place to bed them in, so the first few laps were a "re-bed in" if you will. I came in and checked my lug nuts and made sure everything was ok. After that, it didn't even take a full lap to warm up and I was on my way.
My brake fluid began to boil even with my GT-Sports, so the heat generated by the GT-Rs also began to boil the fluid, leading to increased brake pedal travel. I guess I should also get rid of the factory dust shields, that should help dissapate heat.
For those of you who are unfamiliar with Gingerman, I have included a map. Btwn T11 and T1 as well as T10 and T11 I get up to about 100. From T3 to T5 is essentially a long straight with a slight kink, that section is full out.
first time out I took it easy. I didn't have a proper place to bed them in, so the first few laps were a "re-bed in" if you will. I came in and checked my lug nuts and made sure everything was ok. After that, it didn't even take a full lap to warm up and I was on my way.
My brake fluid began to boil even with my GT-Sports, so the heat generated by the GT-Rs also began to boil the fluid, leading to increased brake pedal travel. I guess I should also get rid of the factory dust shields, that should help dissapate heat.
For those of you who are unfamiliar with Gingerman, I have included a map. Btwn T11 and T1 as well as T10 and T11 I get up to about 100. From T3 to T5 is essentially a long straight with a slight kink, that section is full out.
