[Cloud9...68]

I was on Rennbay's site for a different reason the other day, and I ran across these:



http://www.rennbay.com/944-big-brake-kit-p-83.html



It doesn't say whether they fit on a 968, but what intrigues me, and makes me think they might, is that the previous owner of my car put 944 Turbo S calipers on my car (they really are huge - the pads that go into them make stock 968 pads look like they belong on a toy car), but the guy who installed them had to use a pretty beefy adapter to get them to mate up to my stock spindles (mine isn't an M030 car). Rennbay advertises these calipers as substitutes for the 944 Turbo S calipers, but without the need for the adapters. Visually, the Rennbay calipers look just like mine. They're very reasonably priced, too, and Travis is a really good guy.



I haven't inquired about these myself, as I already have the big calipers, although potentially saving some unsprung weight would be nice, especially with the stout but very heavy RE A-Arms I've installed. But for someone looking to upgrade their front brakes (yes, I know you have to do the rears at the same time), this might be a straightforward, affordable option.

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[flash]

i've run wilwood brakes before on smaller cars. no problems. i've heard horror stories though about them on heavier cars. no idea what's up with that.

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[Cloud9...68]

Yeah, they seem to be a popular brand among racers. As far as I know, there's no difference between 944 and 968 spindles, so I would think these would bolt right up.

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[bva]

also popular among lifted truck owners and for tow vehicles. been looking at wilwood to upgrade the brakes on my full size chevy truck. they're just down the road from me in camarillo. still trying to make time to pay them a visit.

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[Cloud9...68]

Well, I contacted Rennbay about these brakes, and it turns out they will NOT fit on a 968. They were meant as a straightforward upgrade for an N/A 944. According to Travis, they provide about the same braking capability as the 944 turbo, without having to change the spindles to the 944 turbo style spindles, plus they're quite a bit lighter than the 944 turbo calipers. So they sound like a good option for 944 owners.



I learned that the 968 uses 944 turbo spindles, which is why Rennbay's calipers won't work on our cars. In my particular case, the previous owner installed 944 Turbo S calipers, which apparently came with the 944 M030 option. But mine isn't an M030 car, so he had to use adapters to get these monster calipers to fit my stock 968 (aka 944 turbo) spindles. So I apparently have about the most braking power that was available on the 944/968 series, but at the expense of a large amount of unsprung weight <img src="/forum/images/smilies/968/mad.gif" class="smilie" alt="" /> . Unfortunately, unless you want to get into some very expensive custom brakes, this is the trade-off we're faced with in these cars. Somebody with more knowledge, please correct any errors in this summary.

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[flash]

nope - that's about right.



after getting my setup for the denali from bear, which was larger rotors and caliper extensions which allowed you to use the stock calipers, resulting in a 30% braking improvement, without all that much weight added, i toyed around with the idea of some similar caliper extensions, and then fully floating aluminum hat rotors, but i never finished that project. i have more brake than i use now (i learned to drive in a momentum car, so i don't use the brakes much, even on the track), so adding more seemed silly. i still have the aluminum hats, and somewhere around here i have the drawings for the adaptors. maybe someday i'll finish it, but i'll never market it. the liability is just too high.



but i'm sure somebody else could do it too.

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[bombfactory]

I'm waiting for someone to do a Boxster S/Cayman S brake adapter kit for the 968. (mostly for looks, as Flash said. I know I really don't need more brake on this car)



Still waiting.

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[Cloud9...68]

I wish there was something I could do to cut out some of the unsprung weight my calipers add to my car. I also agree that this car really doesn't need more brake, but seeing as I hope to be driving on some faster, less technical tracks sometime before I die (or get this car running again, which may be close to the same time...), I don't think I want to go all the way back to stock brakes.

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[Eric_Oz_S2]

The stock brakes are not too bad, depending on the tyre and pad you use. I run Hoosier r6 and pfc pads and they have more than enough breaking power on the track. I suspect if you run slicks and wider tyres they would be at heir limit. In which case the 928gts brakes (big blacks) can be fitted. These will work with larger cayenne rotors which re cheapno replace.

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[Cloud9...68]

I'm running (well, if the car were actually running...) 18 x 8.5 front/18 x 10 rear, 255/35, 285/35 Hankook R-S3's. At this point in my theoretical track driving "career", braking power is the least of my concerns, so the 944 Turbo S calipers with Zimmerman cross-drilled rotors (not sure of the diameter, but they're big) that I have are gross overkill, and I have heartburn over how much this setup weighs. I'm wondering if going down to 944 NA spindles, and then going with Rennbay's Willwood calipers, with some "in-between" sized rotors, wouldn't be a decent package, as it would give braking power equivalent to a non-MO30 944 turbo, while being much lighter than what I have now. But of course I'd have to balance this with what I have in the back, which I believe is also some version of a 944 Turbo S M030 setup. None of this is much of a priority right now - priority 1 is taking care of my car's remaining issues, and then getting some serious seat time at Driveway Austin.

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[Lear35A]

Granted that unsprung weight is best minimized. However, I don't see how a car can have too much brake any more than have too much horsepower.

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[flash]

lol - i can see having either one, and have driven cars with each. unfortunately they each lacked the other.

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[Joes]

I have a 924s with the M030 struts with 928S4 (big blacks) up front and 944 turbo fronts on the rear. I am here to tell you when you are on lap 15 at Road Atlanta coming down the back straight braking from 120+MPH you can't have enough brakes, damn how much more they weigh.

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[Cloud9...68]

[quote name='Joes' timestamp='1367612411' post='142249']

I have a 924s with the M030 struts with 928S4 (big blacks) up front and 944 turbo fronts on the rear. I am here to tell you when you are on lap 15 at Road Atlanta coming down the back straight braking from 120+MPH you can't have enough brakes, damn how much more they weigh.

[/quote]

I'm sure that's correct. But so far, I've only driven on very tight, highly technical tracks where my fastest lap times have come where I've done the least amount of braking possible. As I progress to faster tracks, I'm sure I'll come to appreciate braking power a lot more. But if you have huge, heavy brakes (including large, heavy rotors), you pay the price digging your way out of corners in an already relatively underpowered car. Plus, you pay for the unsprung weight in other places around the track (particularly the bumpy areas). So, it seems to me that in a car with a modest weight/power ratio like ours, there needs to be a balance between braking power, rotating mass, and unsprung weight. If only there were an affordable, aftermarket ceramic rotor/lightweight caliper available. But if there was, you can bet it wouldn't be available for a car as low volume as a 968!

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[bombfactory]

Anyone know what the weight penalties are for M030, 928 and Big Red brakes over the std. 968 setup?

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[Lear35A]

[quote name='Joes' timestamp='1367612411' post='142249'] I am here to tell you when you are on lap 15 at Road Atlanta coming down the back straight braking from 120+MPH you can't have enough brakes, damn how much more they weigh.[/quote]

Very well put. Larger brakes not only give you more braking power, they also give more area to dissapate heat. I'm not sure ceramics are the answer, but they sure are expensive.

Big brakes are good. Bigger brakes are better.

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[netopyer]

excuse me to dig out  this old topic, but does anybody know, if the 986 boxster S calipers will  fit m030 968 ?

it has 130mm between  fitment hole centers so it should be  possible,  but 986S uses 28mm thick  disc and 968 m030 is 32mm 

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