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Discussion Starter · #1 ·
As the question states. The 4 wheel 355mm disc brake system is a little much. too much braking power in the rear. I emailed Stoptech to see if this is possible.

Is the front and rear caliper mounts the same?
 

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There is a two-wheel front brake (332mm), and there is a four-wheel
332mm brake, but they are not the same.

I have the 332 front brakes on my car, and I asked StopTech if I could later add the rear brakes, in the event I opted to do that.

The answer is "no," because the pistons on the two-wheel setup are different from the pistons on the four-wheel hardware, and there is some
considerable difference in braking balance.

Essentially, if you want to put their brakes on all four corners, do that
at the outset, or plan on running with just the two-wheel setup.

Personally, I find the fronts more than adequate for the street, but if you plan on doing some serious autocrossing, then slap on all four. The price for four corners is approximately 2x the two-wheel price.

If you have any questions, the technical guru at StopTech is a man by the
name of Matt Weiss, and he's very knowledgeable and very helpful.

The number I have for him is 310.325.4799, ext 105.
 

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Discussion Starter · #3 ·
Yea i emailed Matt a little while ago. Imma have to wait from what he says. But what your information is quite a bit informative. Thanks, didnt know much that it'd be an unbalance on the braking difference. Been reading up on the brake system kits from stoptech and all its technical specifications.

I'll have to wait on matt. the 355mm kit looks like they could be on the same mounting bracket style. but for 355mm 4 wheel kit, seems a bit much power for the rear. dont want the rears locking up...
 

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Discussion Starter · #4 ·
By the way rseifer, how much difference do you feel with the 332mm kit in the front?

What kind of pads can you get when you are worn out? and the rotors? would stoptech offer these? I was wondering if you could add Endless pads ..

Too bad stoptech dont have 100-0, 80-0, and 60-0 or some footage of stopping power.
 

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The brakes are "normal" in regular traffic, but if you make a couple of easy stops, and then get some heat in them, they are superb, and feel like you can almost stand the car on the front bumper.

When I put them on, I not only used the stainless lines on the front, but also on the rear. There is a huge difference on the pedal.

The pads are said to be the same as on some Porsche models, and StopTech has extra pads. After I got the brakes on the car, I drove over
to have Matt Weiss take a look at the discs and see what he thought about the color on both the front and rear, which had picked up some bluing from additional heat caused by better balance between the StopTech front and the stock rears.

In talking with him, I mentioned that the new linings were really throwing off a lot of crap on the wheels (although that seems to have reduced after the first week or two), and Matt said they had Axxis pads which were a little cleaner. I wanted to purchase a set of backup linings, and I bought those, although I don't plan to install them until the originals wear out.

I wash the car with a bucket and a brush, and the front wheels clean up ok
when I wash it. It's not a big deal.

The impression I have from speaking with Matt is that replacement pads
should not be a big problem.
 

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The 332s will NOT fit the rear. The caliper will not clear the hub/parking brake drum or something. I don't know of any 4 wheel 332 kit. The 355s will fit because they clear the entire rear brake assembly. If you decide to get the front kit, you can not upgrade to the 4 wheel kit. You will have to buy the entire 4 wheel kit because the piston sizes are different between the kits to compensate for the added braking in the rear (that is, for the 4 wheel kit).
 

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Hey guys, since I have the 355mm Stoptech front & rear kit, let me chime in on this. First, Matt and Stoptech are great. 2nd, the only way you can later on upgrade to all 4 wheel Stoptech system is to go with the 355mm front. The 332mm will NOT fit as mentioned earlier. Also mentioned, although the 4 wheel kit has the same size rotors 355mm front & back, difference is the piston sizes in the calipers for the front & back that makes the brakes kit balanced and thus not requiring modulation of front & rear brake distribution. Stoptech has done their R & D on their brake system obviously. What got me to go with them in choosing my brakes was the result from last year's Ultimate Street Car Challenge (by Sports Compact Car Mag.). Where in braking competion, 2 out of 10 cars entered with the 355mm 4 wheel Stoptech kit took 1st & 2nd place..enough said in rear life application. I feel that the brakes are worth every penny. Braided Steel brake lines are a must, and I also opted for the Motul 600 brake fluid. Hope this helps guys if I didn't basically repeat what others have already said, but just saying from my "personal" on-hand experience..."Stop on a dime at whatever speed" (literally)...:)
 

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What where the cars,tires,etc BTW? 2 out of 10 is nice but by no means scientific. Id too would like to see breaking distances.

isman said:
Hey guys, since I have the 355mm Stoptech front & rear kit, let me chime in on this. First, Matt and Stoptech are great. 2nd, the only way you can later on upgrade to all 4 wheel Stoptech system is to go with the 355mm front. The 332mm will NOT fit as mentioned earlier. Also mentioned, although the 4 wheel kit has the same size rotors 355mm front & back, difference is the piston sizes in the calipers for the front & back that makes the brakes kit balanced and thus not requiring modulation of front & rear brake distribution. Stoptech has done their R & D on their brake system obviously. What got me to go with them in choosing my brakes was the result from last year's Ultimate Street Car Challenge (by Sports Compact Car Mag.). Where in braking competion, 2 out of 10 cars entered with the 355mm 4 wheel Stoptech kit took 1st & 2nd place..enough said in rear life application. I feel that the brakes are worth every penny. Braided Steel brake lines are a must, and I also opted for the Motul 600 brake fluid. Hope this helps guys if I didn't basically repeat what others have already said, but just saying from my "personal" on-hand experience..."Stop on a dime at whatever speed" (literally)...:)
 

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I guess you don't know about the Ultimate Street Car Challenge. Out of thousands of cars, just 10 cars get picked. The 10 cars go thru same controlled tests. Out of the 10 cars the only two cars with the Stoptech kit won 1st & 2nd. As for cars, they were I believe Supra and Viper? (not very light cars) Tires, most of the competitors used DOT Hoosiers. I don't remember the braking distances but they were excellent compared to listed braking distances of other sports cars. They also did other brakes tests besides distance such as brake fade, modulation, and pedal feel. You can go look it up at Sports Compact Car Magazine website. Besides that, I can speak from on-hand experience of the performance of the brake kit, as to other Stoptech owners having same or similar praise. Hope that answers your question.


going4boost said:
What where the cars,tires,etc BTW? 2 out of 10 is nice but by no means scientific. Id too would like to see breaking distances.

isman said:
Hey guys, since I have the 355mm Stoptech front & rear kit, let me chime in on this. First, Matt and Stoptech are great. 2nd, the only way you can later on upgrade to all 4 wheel Stoptech system is to go with the 355mm front. The 332mm will NOT fit as mentioned earlier. Also mentioned, although the 4 wheel kit has the same size rotors 355mm front & back, difference is the piston sizes in the calipers for the front & back that makes the brakes kit balanced and thus not requiring modulation of front & rear brake distribution. Stoptech has done their R & D on their brake system obviously. What got me to go with them in choosing my brakes was the result from last year's Ultimate Street Car Challenge (by Sports Compact Car Mag.). Where in braking competion, 2 out of 10 cars entered with the 355mm 4 wheel Stoptech kit took 1st & 2nd place..enough said in rear life application. I feel that the brakes are worth every penny. Braided Steel brake lines are a must, and I also opted for the Motul 600 brake fluid. Hope this helps guys if I didn't basically repeat what others have already said, but just saying from my "personal" on-hand experience..."Stop on a dime at whatever speed" (literally)...:)
 

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Im not debating you but, the butt feeling doesnt justify 5k for a big brake kit. 8) Alot of what you feel could be initial bite.

I read that the simple changing of tires on the is300 put its breaking distance 70-0 under a m3(157 feet).

If the challenge had 2 of the same cars one with the kit one with out then It would be more valuable to me.(I am familar with it FYI)

I dont doubt the stoptechs are great. But we all know that most of the braking is done by the front wheels so why put a 2500 worth or breaks on the rear?

From the little I know the big deal of the big breaks is reduce fade, more so then stopping distance. For all I know for 99% of the use a set of stickier wider tires and more aggressive pads might give you more then the big brake kit will.

Im a numbers guy :lol: I like comparisons. The one I read of stoptechs on the Zs for the money where not impressive at all.


isman said:
I guess you don't know about the Ultimate Street Car Challenge. Out of thousands of cars, just 10 cars get picked. The 10 cars go thru same controlled tests. Out of the 10 cars the only two cars with the Stoptech kit won 1st & 2nd. As for cars, they were I believe Supra and Viper? (not very light cars) Tires, most of the competitors used DOT Hoosiers. I don't remember the braking distances but they were excellent compared to listed braking distances of other sports cars. They also did other brakes tests besides distance such as brake fade, modulation, and pedal feel. You can go look it up at Sports Compact Car Magazine website. Besides that, I can speak from on-hand experience of the performance of the brake kit, as to other Stoptech owners having same or similar praise. Hope that answers your question.


going4boost said:
What where the cars,tires,etc BTW? 2 out of 10 is nice but by no means scientific. Id too would like to see breaking distances.

isman said:
Hey guys, since I have the 355mm Stoptech front & rear kit, let me chime in on this. First, Matt and Stoptech are great. 2nd, the only way you can later on upgrade to all 4 wheel Stoptech system is to go with the 355mm front. The 332mm will NOT fit as mentioned earlier. Also mentioned, although the 4 wheel kit has the same size rotors 355mm front & back, difference is the piston sizes in the calipers for the front & back that makes the brakes kit balanced and thus not requiring modulation of front & rear brake distribution. Stoptech has done their R & D on their brake system obviously. What got me to go with them in choosing my brakes was the result from last year's Ultimate Street Car Challenge (by Sports Compact Car Mag.). Where in braking competion, 2 out of 10 cars entered with the 355mm 4 wheel Stoptech kit took 1st & 2nd place..enough said in rear life application. I feel that the brakes are worth every penny. Braided Steel brake lines are a must, and I also opted for the Motul 600 brake fluid. Hope this helps guys if I didn't basically repeat what others have already said, but just saying from my "personal" on-hand experience..."Stop on a dime at whatever speed" (literally)...:)
 

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That's nice. :).

going4boost said:
Im not debating you but, the butt feeling doesnt justify 5k for a big brake kit. 8) Alot of what you feel could be initial bite.

I read that the simple changing of tires on the is300 put its breaking distance 70-0 under a m3(157 feet).

If the challenge had 2 of the same cars one with the kit one with out then It would be more valuable to me.(I am familar with it FYI)

I dont doubt the stoptechs are great. But we all know that most of the braking is done by the front wheels so why put a 2500 worth or breaks on the rear?

From the little I know the big deal of the big breaks is reduce fade, more so then stopping distance. For all I know for 99% of the use a set of stickier wider tires and more aggressive pads might give you more then the big brake kit will.

Im a numbers guy :lol: I like comparisons. The one I read of stoptechs on the Zs for the money where not impressive at all.


isman said:
I guess you don't know about the Ultimate Street Car Challenge. Out of thousands of cars, just 10 cars get picked. The 10 cars go thru same controlled tests. Out of the 10 cars the only two cars with the Stoptech kit won 1st & 2nd. As for cars, they were I believe Supra and Viper? (not very light cars) Tires, most of the competitors used DOT Hoosiers. I don't remember the braking distances but they were excellent compared to listed braking distances of other sports cars. They also did other brakes tests besides distance such as brake fade, modulation, and pedal feel. You can go look it up at Sports Compact Car Magazine website. Besides that, I can speak from on-hand experience of the performance of the brake kit, as to other Stoptech owners having same or similar praise. Hope that answers your question.


going4boost said:
What where the cars,tires,etc BTW? 2 out of 10 is nice but by no means scientific. Id too would like to see breaking distances.

isman said:
Hey guys, since I have the 355mm Stoptech front & rear kit, let me chime in on this. First, Matt and Stoptech are great. 2nd, the only way you can later on upgrade to all 4 wheel Stoptech system is to go with the 355mm front. The 332mm will NOT fit as mentioned earlier. Also mentioned, although the 4 wheel kit has the same size rotors 355mm front & back, difference is the piston sizes in the calipers for the front & back that makes the brakes kit balanced and thus not requiring modulation of front & rear brake distribution. Stoptech has done their R & D on their brake system obviously. What got me to go with them in choosing my brakes was the result from last year's Ultimate Street Car Challenge (by Sports Compact Car Mag.). Where in braking competion, 2 out of 10 cars entered with the 355mm 4 wheel Stoptech kit took 1st & 2nd place..enough said in rear life application. I feel that the brakes are worth every penny. Braided Steel brake lines are a must, and I also opted for the Motul 600 brake fluid. Hope this helps guys if I didn't basically repeat what others have already said, but just saying from my "personal" on-hand experience..."Stop on a dime at whatever speed" (literally)...:)
 

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Discussion Starter · #12 ·
okay. I've found my answer to my question a little bit ago. No need for repititious answers.

Matt Weiss said:
The reason we must go w/ a 355 rear is due to the diameter of the parking
brake mechanism that lives inside the rotor hat. Only a 355mm hat is large
enough to clear, a 332mm rotor hat will not. Rotor size is only part of the
formula for computing brake torque. The diameter of the pistons in the
caliper also has an effect on how much force is applied. We size the
pistons in both front and rear calipers to maintain the proper balance, so
although the rear rotor is 355mm, we are not adding more rear bias as we use
smaller caliper pistons in the rear.

Please let me know if you have any other questions-

Matt Weiss
StopTech
 

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Ah From the horse mouth(stoptech) Big brake kits will not significantly reduce distance. It will be no longer though. It will improve fade, feel, etc. I had no break fade on my car on the track so I guess it answers my question.
 
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