Boxster s brakes on a non s

[duncan00]

Hi there

I was wondering if someone could confirm this for me please.

I'm looking to put a set of S brakes on my 99 Boxster. I believe the only thing i need is 17" or above rims (I have 18's) for the addtional size of calipers/discs??

Is this correct will the S calipers and discs fit directly to my car?

Thanks in advance for your help

Regards

Duncan

[mee]

No, they will not directly fit. The fronts will, but the rears will not due to different parking brake arrangements. If you surf, you will find a couple of people who have done different modifications to get the rears to work--one modifying the S brakes/rotors and the other modifying the stock side.

[Peter986]

No, they will not directly fit. The fronts will, but the rears will not due to different parking brake arrangements.

This is correct. The problem is that the brake drum on the inside of the rear caliper (for the e-brake) is a different diameter on the S brakes. I have 996 calipers and rotors (same as S) on the front of my car and just left the stock brakes on the rear. These work just fine.

[JFP in PA]

Hi there

I was wondering if someone could confirm this for me please.

I'm looking to put a set of S brakes on my 99 Boxster. I believe the only thing i need is 17" or above rims (I have 18's) for the addtional size of calipers/discs??

Is this correct will the S calipers and discs fit directly to my car?

Thanks in advance for your help

Regards

Duncan

Brembo makes a special rotor for the rear, "S" diameter & cross drilled so it will accept the calipers, but the ebrake drum is machined to "base" specs, so it will bolt right on...................

[duncan00]

Hi there

Thanks very much for your help everyone.

JFP is this a conversion you have done? Do you have the part numbers for the brembo rotors?

Cheers

Duncan

[duncan00]

Sorry me again I'm getting differing views on this.... can anyone please please tell me if this conversion is possible..... I'm really confused and don't want to go to the expensive of buying the rest of the parts only to find the rears don't fit.

Has anyone done this conversion and if so did you have to use any special parts?

So far I've had a few places say easy change.... and others say not sure never tried.... and others say no!!!!

Didn't realise it would be so hard!! :(

So far I've....

E-mailed Brembo (no response)

Spoken to local Porsche dealer in UK (no conversion kit available)

Spoken to an independant in UK (not a problem)

Suncoast Porsche (not sure if it's possible)

Spoken to a breakers yard in UK(3.2 and 2.5 have different e-brake set up never tried to put s on standard so not sure)

Thanks very much for all your help guys.

Cheers

Duncan

[JFP in PA]

Sorry me again I'm getting differing views on this.... can anyone please please tell me if this conversion is possible..... I'm really confused and don't want to go to the expensive of buying the rest of the parts only to find the rears don't fit.

Has anyone done this conversion and if so did you have to use any special parts?

So far I've had a few places say easy change.... and others say not sure never tried.... and others say no!!!!

Didn't realise it would be so hard!! :(

So far I've....

E-mailed Brembo (no response)

Spoken to local Porsche dealer in UK (no conversion kit available)

Spoken to an independant in UK (not a problem)

Suncoast Porsche (not sure if it's possible)

Spoken to a breakers yard in UK(3.2 and 2.5 have different e-brake set up never tried to put s on standard so not sure)

Thanks very much for all your help guys.

Cheers

Duncan

You need to contact Bremo's master distributor in the US: Race Technologies at http://www.racetechnologies.com

Yes, a full conversion kit exisits, I have one installed and have done two others, they are a bolt in swap with the kit; which includes the "special" rear rotors that are machined to the base e-brake size, stainless steel lines, new caliper bolts, etc. But be aware the the kit is not cheap..................

Oh, and one kit was purchased from Suncoast, so I have no idea why they are "not sure is it possible"........

[duncan00]

Thanks very much for the info I contacted them and finally got a straight answer!!! The rotors cost $495 each I'm just waiting to find out how much the shipping to th UK is to decide if I'm going to go ahead with it.......

This may be a really stupid question but..... Do you know if I can use a standard disc with the S rear calipers?

Thanks again for your help.

Duncan

[KevinC]

...

This may be a really stupid question but..... Do you know if I can use a standard disc with the S rear calipers?

Thanks again for your help.

Duncan

The standard rotors are 4mm thinner than the S rotors, so it *might* be possible to "hyper-extend" the pistons of the S calipers with the standard rotor. (Probably only a problem if you foolishly manage to extend the pistons all the way to the rotor with no pad in place. I got away with this using S calipers and rotors. I wouldn't want to try it with thinner rotors.) The standard rotors are also smaller in diameter so the pads in S calipers would overhang the rotor. All this said, I know that folks have gotten away with simply moving standard Boxster front calipers to the rear, which is a pretty similar situation to putting rear Boxster S calipers on the rear of a standard Boxster.

The rear brakes are not prone to overheating, so the only reason to upgrade them would be to maintain similar front/rear bias. Brake torque is determined primarily by three factors: the "bite" of the pads, the size of the caliper pistons and the diameter of the rotor. I'm pretty sure Boxster S front pistons are the same size as those in the standard Boxster calipers. That means that the only factor giving you more bias to the front is the slightly larger diameter of the Boxster S rotor. I would probably just leave the rear brakes as they are and let your nice new big front brakes take a little higher percentage of the load.

[duncan00]

Okay sorry I have another question.... the shipping on the rotors came in at $295.... although they have offer to reduce the cost of the discs to allow for this... I'm still debating this in my head. I have however had an e-mail this morning with another suggestion by a Porsche specialist in the UK as follows.....

Duncan,

You need to use the complete S upright/disc/handbrake assembly on the

rear

because the discs are a different offset and the 2.5 has a smaller

diameter

handbrake assembly. It is possible to "fiddle" the S caliper onto the

stock

2.5 disc but I do not believe that it is worth the effort. If you shop

around you should be able to find the parts at a breakers cheap enough.

Kind Regards,

What do those technical people think of this.... do you see any fitment issues?

As always thanks for your help.

Duncan

[JFP in PA]

Okay sorry I have another question.... the shipping on the rotors came in at $295.... although they have offer to reduce the cost of the discs to allow for this... I'm still debating this in my head. I have however had an e-mail this morning with another suggestion by a Porsche specialist in the UK as follows.....

Duncan,

You need to use the complete S upright/disc/handbrake assembly on the

rear

because the discs are a different offset and the 2.5 has a smaller

diameter

handbrake assembly. It is possible to "fiddle" the S caliper onto the

stock

2.5 disc but I do not believe that it is worth the effort. If you shop

around you should be able to find the parts at a breakers cheap enough.

Kind Regards,

What do those technical people think of this.... do you see any fitment issues?

As always thanks for your help.

Duncan

I do not konw who this "specialist" is, but he is not correct on this issue. I have the Brembo kit on my car, I've installed it on two others, there is no "fitment" issues, no "offset" issues or need to change ANYTHING ELSE to put them on the car, period. They simply replace the exsiting rotors, with the new caplipers ("S" version) and bolt on. You need to stop worrying about it, buy the correct parts and get on with it............................They fit!!!!!

[duncan00]

Hi JPA

Thanks for the info.... I realise they will fit as you've mentioned however the price tag of $1,000 is putting me off a little bit.... was trying to come up with a cheaper solution.

The people in the UK's suggestion was if I wanted to use the S rotors I'd need to replace the other bits.... as they don't sell modified rotors.

I'll stop bugging you now and get it sorted either way. :)

Cheers

Duncan

[JFP in PA]

Hi JPA

Thanks for the info.... I realise they will fit as you've mentioned however the price tag of $1,000 is putting me off a little bit.... was trying to come up with a cheaper solution.

The people in the UK's suggestion was if I wanted to use the S rotors I'd need to replace the other bits.... as they don't sell modified rotors.

I'll stop bugging you now and get it sorted either way. :)

Cheers

Duncan

Because the factory "S" uses the six speed, the rear hubs (and several other components) are different, including the rotor and ebrake size. While a base car can be converted over to all these "S" components, the price to do so is totally outrageous; hence Brembo introduced the "Big Reds" kit to change the base car over to "S" brakes by using the special rear rotors. The total kit used to cost in the $3K (US) range and had every possible part you would need, including braided stainless steel brake lines, which are a very nice additon to any car. The price for the kit was less than half the price for the OEM components to get the car ready to accept the OEM "S" brakes set up. As I've mentioned, I have one on my Boxster, and have installed two other kits, it is a simple bolt on swap, but expensive...............

Edited June 21, 2006 by JFP in PA

[duncan00]

Ah okay so the disc is part of the big red upgrade kit.... I'll speak to some porsche parts places here and find out how much the disc will be.....

Thanks again for all your help.... hopefully that'll be the last question I ask :)

Cheers

Duncan

[JFP in PA]

Ah okay so the disc is part of the big red upgrade kit.... I'll speak to some porsche parts places here and find out how much the disc will be.....

Thanks again for all your help.... hopefully that'll be the last question I ask :)

Cheers

Duncan

Brembo Kit: 894.5986R Boxster 97-03 Front & Rear minimum wheel size: 17" Front rotor diam: 12.5" 318 mm Cost : $3,250 (US$)

Enjoy!