StopTech C43 vs StopTech Trophy Front BBK. Pls help me decide

[SQ13]

Hey guys. I’m planning on buying a front BBK for my track car (~3260 with driver and 8 gal of fuel), and I am having a hard time deciding between the ST C43 332mm kit and the ST Trophy ST40 355mm kit.

The C43 kit is lighter, but the Trophy will offer better heat dissipation. Replacement pads for the C43 are much cheaper and friction rings are slightly cheaper vs Trophy, but the Trophy’s 355mm rings (and probably pads, too) will need to be replaced less often. Can y’all offer your input on why you would go with one kit over the other?

Another thing that I’m concerned about is the ability to add a rear BBK without ruining the bias. The C43 rear kit is definitely a no go, since the parking brake has to be deleted. The 996 conversion is appealing, but I’m unable to figure out the C43 + 996 bias because my request to access clawhamm3r’s calculator isn’t approved. If someone’s willing to help with the calculation, I have the C43 caliper’s piston sizes (38/44mm). Looking at p0lar’s chart, it appears the 996 conversion is doable with the Trophy kit.

Finally, I have the option to add piston dust boots for both kits. For a track car that is driven to/from the track, what are the pros and cons? I’d like to add dust boots, but my concern is that they’ll degrade quickly due to track use (heat). Without dust boots, how often would the calipers need to be rebuilt?

Thanks

[ra2fanatic]

Do it once and do it right. Mind you, my M3 won't be seeing any tracks, but you are thinking way ahead for front and rear bias along with longevity, so spend a bit more and get the 6/4 setup from Stoptech.

[Nihilation]

This post may be useful in your decision: https://nam3forum.com/forums/forum/s...9132#post69132

I'm in the process of installing the C43 kit, myself. If interested, on instagram: @rightfootdown
Speaking with StopTech's technical resource, Robert, no dust boots isn't a big deal if you check for debris periodically. Even when I prodded, he made no effort to recommend the more expensive ST40 or ST60 kit over the C43 for a weekend street/track car. The calipers are not designed for dust boots and StopTech doesn't offer them. If you have a way of adding them, I'm interested to hear about it.

Lastly, I can get you this kit for under $2k shipped. There isn't inventory for this kit so you'll have to wait 2-3 months. Took me a little less than 3 for mine to arrive.

[SQ13]

Do it once and do it right. Mind you, my M3 won't be seeing any tracks, but you are thinking way ahead for front and rear bias along with longevity, so spend a bit more and get the 6/4 setup from Stoptech.

Nah, six piston calipers are excessive. I’m only interested in the two kits I mentioned.

[SQ13]

This post may be useful in your decision: https://nam3forum.com/forums/forum/s...9132#post69132

I'm in the process of installing the C43 kit, myself. If interested, on instagram: @rightfootdown
Speaking with StopTech's technical resource, Robert, no dust boots isn't a big deal if you check for debris periodically. Even when I prodded, he made no effort to recommend the more expensive ST40 or ST60 kit over the C43 for a weekend street/track car. The calipers are not designed for dust boots and StopTech doesn't offer them. If you have a way of adding them, I'm interested to hear about it.

Lastly, I can get you this kit for under $2k shipped. There isn't inventory for this kit so you'll have to wait 2-3 months. Took me a little less than 3 for mine to arrive.

I’ve actually gone thru that thread and contacted you regarding the kit. I’m currently working with Adam to purchase a BBK, but C43 vs Trophy is where I am stuck. The price difference between the two is $500 if I buy from him.

Something I noticed while looking at your Instagram photos is that while the rotors are advertised as having pillar vanes, your rotors have the traditional curved vanes. Can you comment on that?

Adam gave me the option to add dust boots to the C43 kit, but maybe he was mistaken. I’ll ask for clarification. Can you expand on maintenance/care of dust boot-free pistons? Debris will definitely be present, so would I just wipe it off from time to time, maybe every six months? Did they say anything on how often rebuilds would be required?

[ra2fanatic]

Nah, six piston calipers are excessive. I’m only interested in the two kits I mentioned.

I mean don't go with the 6 pot then, Trophy comes in 4pot.

[SQ13]

Bump. I would really like to get an answer on my brake bias question at least. My request to access the calculator still hasn’t been approved.

[bigjae46]

6 pot calipers - not really worth it IMO. The advantage is you get more backside wheel spoke clearance. Really not needed in this case. The real problem is suspension clearance.

I drive with a guy who had the front only ST40/355mm BBK. I have a 4 wheel BBK...my pads lasted 2-3 weekends longer. The cars were very similar in every other aspect (I was a little lighter, he had more power and 4.10 gears). I had not installed brake ducts yet.

In fact, his pads didn't last much longer than the stock pads. Performance was good, not quite as good as the 4 wheel. I'm out-braking him in every heavy braking zone.

The rear BBK makes a bigger difference than you think...

C43 vs ST40? The primary advantage is less unspring weight - probably 4-5 lbs per corner?

[pnvhome]

I use front calipers from Alfa Gulia quadrofolio, with 355/32 rotors, and rear from porshe with 345/24 rotors, works absolutely perfect

[Ianb]

Pnvhome - Believe I read the front calipers are 34 and 38mm pistons, can you confirm this and is it two 34mm and one 38mm or a different combination?

Where did you get the front brake discs, are they custom?

Thanks

[pnvhome]

Pnvhome - Believe I read the front calipers are 34 and 38mm pistons, can you confirm this and is it two 34mm and one 38mm or a different combination?

Where did you get the front brake discs, are they custom?

Thanks

According documentation it is - 6 Pistons of : 38 - 34 - 30, disks are custom from brembo and some handmade, pads are hawk, and also additional custom fastenings, also a little problem in design even apex ec7r (18) need 5mm spacers to fit ok)
In any case, these brakes are quietly enough to brake from 250 km / h without severe overheating, the stock brakes died already by 150 km / h when decelerating from 250. And price for that about 3800$ for front and rear.

[SQ13]

6 pot calipers - not really worth it IMO. The advantage is you get more backside wheel spoke clearance. Really not needed in this case. The real problem is suspension clearance.

I drive with a guy who had the front only ST40/355mm BBK. I have a 4 wheel BBK...my pads lasted 2-3 weekends longer. The cars were very similar in every other aspect (I was a little lighter, he had more power and 4.10 gears). I had not installed brake ducts yet.

In fact, his pads didn't last much longer than the stock pads. Performance was good, not quite as good as the 4 wheel. I'm out-braking him in every heavy braking zone.

The rear BBK makes a bigger difference than you think...

C43 vs ST40? The primary advantage is less unspring weight - probably 4-5 lbs per corner?

1) RIP, TWS

2) TWS CW looks really fun. I only got to run it in CCW

3) Were y’all using the same pads?

4) I def want a rear brake kit as well. The issue right now is, I don’t know what rear kit I can pair with the front C43 kit. Without access to the calculator and no one to help me out, I can’t proceed with purchase.

5) Yeah, C43 offers about a 5 lb reduction per corner. Do you think the ST40 with 355mm rotors would outbrake the C43 with its little 332mm rotors?

[maupineda]

1) RIP, TWS

2) TWS CW looks really fun. I only got to run it in CCW

3) Were y’all using the same pads?

4) I def want a rear brake kit as well. The issue right now is, I don’t know what rear kit I can pair with the front C43 kit. Without access to the calculator and no one to help me out, I can’t proceed with purchase.

5) Yeah, C43 offers about a 5 lb reduction per corner. Do you think the ST40 with 355mm rotors would outbrake the C43 with its little 332mm rotors?

I have made my own calculator to compare different setups. I think you can start from here, there are multiple factors not accounted but it would serve as a baseline to compare different setups all else equal. I can send you the file in an email, as it gave me an error here.

One thing I have always wondered about is why no one has ever pointed that from a pure brake torque perspective, the OE ZCP callipers provide more clamping force than the Porsche setup. in fact, not even the DB9 callipers with 40/44 pistons would provide the same clamping force as the 60mm floater. The newer option (Renault Megane callipers) with 2 40mm pistons would be better than the Porsche's, but nowhere near the OE ZCP. Food for thought I guess

This was also part of the reasoning behind my calliper selection (135i + 996). which is better than a pure 996 setup from a clamping force perspective.

[r4dr]

Does clamping even matter? I haven’t heard anyone say they can’t push hard enough to engage ABS with any brake setup on these cars?

That’s an honest question, I’ve never considered clamping force much.

[maupineda]

Does clamping even matter? I haven’t heard anyone say they can’t push hard enough to engage ABS with any brake setup on these cars?

That’s an honest question, I’ve never considered clamping force much.

I think it does, why wouldn’t it? Is just as important as rotor diameter, etc. Is a factor to consider as part of the whole package. I did notice that with my setup it does take a bit more effort to trigger the ABS.

if you move to a larger rotor, or change to a more aggressive pad, then you can compensate for that, but if keeping OE size rotors and similar pad compound, is an important factor in my book. This was my case as I kept using Textar pads and OE rotors.

what I do agree 100% with everyone is the extreme improvement in brake pedal feel and consistency