Potential Brake Bias problem
05-31-2005, 09:20 PM
#1
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Potential Brake Bias problem
Over a year ago, I bought a set of 930 calipers and 964 calipers from someone to install on my 87 911. I'm finally getting around to installing them and noticed that the 930 calipers (which are for the front) are actually 930 rear calipers, so instead of the 4x38mm pistons, I have 4x30mm pistons. Crap!
This gives me an overall piston area that is less than the Boxster caliper that is coming off the car (I'm sick of cooking rotors). So, I guess my question is, will using these 930 rear calipers (on the front) cause a rearward brake bias with the 964 caliper (or even the stock Carrera rear caliper) with the p/v left in? I also have an adjustable bias valve that I could replace the p/v with.
I know it's not the best solution, but until I get something better, I'd like to have brakes. So I'd like to use this as a short term solution if it won't spin the car every time I hit the brakes.
This gives me an overall piston area that is less than the Boxster caliper that is coming off the car (I'm sick of cooking rotors). So, I guess my question is, will using these 930 rear calipers (on the front) cause a rearward brake bias with the 964 caliper (or even the stock Carrera rear caliper) with the p/v left in? I also have an adjustable bias valve that I could replace the p/v with.
I know it's not the best solution, but until I get something better, I'd like to have brakes. So I'd like to use this as a short term solution if it won't spin the car every time I hit the brakes.
05-31-2005, 10:42 PM
#2
RL Technical Advisor
Hi:
The very first thing I would ask is what rotors (F&R) are you going to use? Rear Turbo calipers require a 305x28mm rotor.
You will have bias issues with those 930 calipers w/ 964 rears. If you install a Tilton PV, you can compensate to make it work, although it will not be ideal.
The very first thing I would ask is what rotors (F&R) are you going to use? Rear Turbo calipers require a 305x28mm rotor.
You will have bias issues with those 930 calipers w/ 964 rears. If you install a Tilton PV, you can compensate to make it work, although it will not be ideal.
05-31-2005, 11:06 PM
#3
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The front rotors are 305x28 so they do fit, but I've decided against doing the install. I just talked to my mechanic and he figured I was better off sticking with what I had (as bad as it is) and locating a set of 930 front calipers or an equivilent and doing it properly. So now I'm looking for a front caliper that is a good match for a 930 rear, and front rotors (since the ones I have are 305x28). Maybe I should just sell my house and by a GT-3
06-01-2005, 12:14 AM
#4
RL Technical Advisor
LOL,.."Doing it properly" is really the only way to perform upgrades.
You need a pair of 930 calipers and the correct front rotors to allow those to fit your Carrera.
Of course, a GT-3 is VERY nice, too.
You need a pair of 930 calipers and the correct front rotors to allow those to fit your Carrera.
Of course, a GT-3 is VERY nice, too.
06-01-2005, 10:27 AM
#5
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The problem is that finding half a set of 930 calipers (fronts only) is proving to be difficult. I wonder if my wife would mind living in a GT-3? hmmmm.