Orthojoe .2 GT3 Thread
06-05-2018, 10:18 PM
#226
06-06-2018, 01:00 AM
#228
Nordschleife Master
Thread Starter
Thanks for the informative post, Jeff. So I assume that since there is less total rotor mass and less total pad mass with your AP BBK vs your AP rotor kit for stock calipers, the rotors and pads will wear faster for the same use and need more frequent replacement?
Can you commwnt roughly on what relative service life you expect to see for a stock size pad and AP rotor can the AP BBK for pads and rotors for the same use (based on theory of the material volumes etc.)?
Thanks!
06-06-2018, 01:08 AM
#229
Pad wear rate is DEFINITELY much less with the AP setup than the OEM setup. I just look a look at the DS1.11 pads on my car after 2.5 track days and they barely look worn. On the OEM system the DS1.11 pads would last 6 days at the most. I'm pretty sure with the AP setup they will last at least double.
06-06-2018, 01:18 AM
#230
Nordschleife Master
Thread Starter
Originally Posted by Mech33
Dis you measure thickness before and after? Not sure why wear would be significantly less.
06-06-2018, 02:16 AM
#231
Burning Brakes
I had to remove caster from my 991.1 GT3 RS when I added shims to reach -3.5 camber (wanted to gain camber with shims instead of the strut tops).
The camber curves went poop. I had understeer despite the camber gains. So, I used a LongAcre camber gauge, and measured left front and right front tire camber at 45 degrees steering wheel turn, 90 degrees, 135 and 180 (a half steering turn), turning left and right. I took notes of the different camber readings and I was at nearly -6 degrees at half turn, this is nowhere ideal for a Hoosier as the tire would be riding on the inner edge (hence my understeer).
I dialed back to 9,3 caster (from 10.7) and found the sweet spot for front camber while turning the wheels.
The in-car videos helped me identify the different steering angles I needed while driving, to then calculate the caster that didn't send the camber curves to useless. Ideally you want a lot of caster, but you also want the camber on the outside front wheel to be on the preferred spot for the tires being used when turning, and each racetrack requires a different range of steering wheel angles when turning, so the alignment should be racetrack-specific
The camber curves went poop. I had understeer despite the camber gains. So, I used a LongAcre camber gauge, and measured left front and right front tire camber at 45 degrees steering wheel turn, 90 degrees, 135 and 180 (a half steering turn), turning left and right. I took notes of the different camber readings and I was at nearly -6 degrees at half turn, this is nowhere ideal for a Hoosier as the tire would be riding on the inner edge (hence my understeer).
I dialed back to 9,3 caster (from 10.7) and found the sweet spot for front camber while turning the wheels.
The in-car videos helped me identify the different steering angles I needed while driving, to then calculate the caster that didn't send the camber curves to useless. Ideally you want a lot of caster, but you also want the camber on the outside front wheel to be on the preferred spot for the tires being used when turning, and each racetrack requires a different range of steering wheel angles when turning, so the alignment should be racetrack-specific
06-06-2018, 04:10 AM
#232
BTW I think your AP pad spring block thing is backwards on the right side of your photo...
06-06-2018, 04:33 AM
#233
Rennlist Member
The in-car videos helped me identify the different steering angles I needed while driving, to then calculate the caster that didn't send the camber curves to useless. Ideally you want a lot of caster, but you also want the camber on the outside front wheel to be on the preferred spot for the tires being used when turning, and each racetrack requires a different range of steering wheel angles when turning, so the alignment should be racetrack-specific
I'd be very interested in hearing more about this. I wonder in very tight hairpins whether the camber gain from caster is so much as to reduce front end grip. I've heard some autocross people say as much and recommend smaller caster numbers for autox.
06-06-2018, 09:51 AM
#234
Pro
Neurotic & Drdonger - Car does have Extended Tank, Front Lift & Bose, and tank was Full. Car does not have LED's.
Gt-2, car weighs 3100 lbs empty.
Best Regards,
Dave
Gt-2, car weighs 3100 lbs empty.
Best Regards,
Dave
06-06-2018, 04:15 PM
#235
Nordschleife Master
Thread Starter
Originally Posted by Mech33
LOL tell me about it. Been stuck traveling too much.
BTW I think your AP pad spring block thing is backwards on the right side of your photo...
BTW I think your AP pad spring block thing is backwards on the right side of your photo...
06-06-2018, 05:36 PM
#236
Burning Brakes
My 991.1 GT3 RS on 3 gallons of fuel is at 3,088 lbs, but it has the Ti center muffler (stock), the side mufflers deleted with single L-pipes (not valved), and a set of wheels 27 lbs lighter than stock.
The deletion of the unnecessary side mufflers takes 40 lbs from behind the rear axle, and if you do a Lithium battery to replace the stock brick you get another 35 lbs removed, and an used Ti center muffler is a further 8 lbs. Throw a 2nd set of forged wheels, remove a bunch of tools and the car would be in the 2,9xx lbs range before fuel. Most cars these days have to be made of carbon fiber to get below 3,000 lbs.
06-06-2018, 05:44 PM
#237
The 991.2 GT3 got lighter than the 991.1 GT3. Your car is pretty light at 3,100 lbs with no fuel, considering it has A/C, Bose and Axle lift. The axle lift system was made lighter with the 991.2 (no more mega heavy pump like my 991.1 GT3 RS).
My 991.1 GT3 RS on 3 gallons of fuel is at 3,088 lbs, but it has the Ti center muffler (stock), the side mufflers deleted with single L-pipes (not valved), and a set of wheels 27 lbs lighter than stock
My 991.1 GT3 RS on 3 gallons of fuel is at 3,088 lbs, but it has the Ti center muffler (stock), the side mufflers deleted with single L-pipes (not valved), and a set of wheels 27 lbs lighter than stock
06-06-2018, 05:50 PM
#238
Burning Brakes
wow!! that's going to make the 991.2 GT3 RS even lighter. I'm awaiting for my allocation, and I'm adding axle lift again, makes loading on my trailer a peaceful process.
06-06-2018, 08:57 PM
#239
Pro
I plan to do the Lithium battery and side muffler delete on the RS (my .2 GT3 is all stock). And believe on empty the car will be very close to 3,000 lbs on OEM wheels/tires.
Best Regards,
Dave
