DIY Big Brake Rotor Upgrade?

[Dave80GTSi]

Yes, I did an archive search, but I could not find any info on this particular question!

I am in the process of changing my OEM 17” wheels to the optional 18” OEM wheels, and the new wheel style has a much more “open” spoke construction, meaning that the rotor and calipers behind are now much more visible than before.

I have always been pleased with the braking performance of the OEM set-up (used as a 100% street car), but in trial fitting the new 18” wheels, the rotors now appear to have been downsized (in a relative sense) since there is now more daylight visible between the outside edge of the rotor and the inside edge of the new wheels.

I am aware of the many high quality Big Brake kits which are available – Brembo, StopTech, and the like. These all come with larger calipers, braided lines, better pads, and all of the rest. But in my case I openly admit that my intent here is more cosmetic in nature, and that I do not really need any notable increase in stopping performance.

So, my question: Might anyone know of a readily available OEM front and/or rear rotor, perhaps from another model make or year? Looking for ones which would be roughly about 1” larger in their outside diameter, would be of the correct thickness, and which would properly fit right up to the OEM hubs.

I figure that if I can find these rotor candidates, I then should be able to correspondingly configure the adaptors for the OEM calipers to space them out ½” further away from the hub. I have access to a machine shop which can fabricate the caliper spacers as will be needed, so that part isn’t the concern here.

Thanks - DM

[JFP in PA]

Originally Posted by Dave80GTSi

Yes, I did an archive search, but I could not find any info on this particular question!

I am in the process of changing my OEM 17” wheels to the optional 18” OEM wheels, and the new wheel style has a much more “open” spoke construction, meaning that the rotor and calipers behind are now much more visible than before.

I have always been pleased with the braking performance of the OEM set-up (used as a 100% street car), but in trial fitting the new 18” wheels, the rotors now appear to have been downsized (in a relative sense) since there is now more daylight visible between the outside edge of the rotor and the inside edge of the new wheels.

I am aware of the many high quality Big Brake kits which are available – Brembo, StopTech, and the like. These all come with larger calipers, braided lines, better pads, and all of the rest. But in my case I openly admit that my intent here is more cosmetic in nature, and that I do not really need any notable increase in stopping performance.

So, my question: Might anyone know of a readily available OEM front and/or rear rotor, perhaps from another model make or year? Looking for ones which would be roughly about 1” larger in their outside diameter, would be of the correct thickness, and which would properly fit right up to the OEM hubs.

I figure that if I can find these rotor candidates, I then should be able to correspondingly configure the adaptors for the OEM calipers to space them out ½” further away from the hub. I have access to a machine shop which can fabricate the caliper spacers as will be needed, so that part isn’t the concern here.

Thanks - DM

Your problem of fitting "S" type rotors on the rear of a base car (if that is where you are going) is that the emergency brakes on the base are totally different than the S. To covert the car over to S brakes, you are going to need to swap out the uprights and hub carriers for those from the S, otherwise you will need to go totally after market.

[Dave80GTSi]

Originally Posted by JFP in PA

Your problem of fitting "S" type rotors on the rear of a base car (if that is where you are going) is that the emergency brakes on the base are totally different than the S. To covert the car over to S brakes, you are going to need to swap out the uprights and hub carriers for those from the S, otherwise you will need to go totally after market.

Right, I had found that info already in my search. But in my case, I am starting with an S.

I was hoping to learn, for an example, that perhaps some variant within the 911 line might have come OEM with one size larger OEM rotors, and which would mate up to our 986 hubs.

Thanks - DM

[edc]

Patt on boxa.net has a caliper spacer and larger rotor set up.

[JFP in PA]

Originally Posted by Dave80GTSi

Right, I had found that info already in my search. But in my case, I am starting with an S.

I was hoping to learn, for an example, that perhaps some variant within the 911 line might have come OEM with one size larger OEM rotors, and which would mate up to our 986 hubs.

Thanks - DM

Your S is already carrying the 996 brakes, so you would need to look to the GT cars with iron rotors or aftermarket.

[PaulE]

If you're looking for bigger rotors to fill up the visible gap between the rotor and the rim, how about the GiroDisc rotor upgrade? The bigger disc provides more brake swept area, and they also reduce unsprung weight due to their aluminum center hats. You'll get a performance upgrade even though stock brakes are more than adequate for street use, and you don't need new calipers or pads, just the GiroDisc kit with rotors and bolts.

[Dave80GTSi]

Originally Posted by edc

Patt on boxa.net has a caliper spacer and larger rotor set up.

Thanks - I spent roughly a half-hour last night searching that board for info on either "rotor" or anything as posted by Mr. Patt, only to come up empty. Might you have a thread link there which I have somehow overlooked?

Thanks - DM

[Dave80GTSi]

Originally Posted by PaulE

If you're looking for bigger rotors to fill up the visible gap between the rotor and the rim, how about the GiroDisc rotor upgrade? The bigger disc provides more brake swept area, and they also reduce unsprung weight due to their aluminum center hats. You'll get a performance upgrade even though stock brakes are more than adequate for street use, and you don't need new calipers or pads, just the GiroDisc kit with rotors and bolts.

Thank you for the tip! That sounds like just the ticket!

However, searching Girodisc's website,. I see no 986 listings. But they do offer this F&R pair for the 996 C2/C4 series: Rotors

Are they interchangeable back to the 986?

Even so, $2200. USD for a set of 4 rotors above does seem pretty dear. I was hoping to find an OEM candidate which one could pick up for less money than that.

Thanks - DM

[edc]

It's not listed on the website but contact Freakyparts Ltd. If you search under username Patt you should find a thread on his now old blue 986 with the brake mod fitted. Rotor in UK is more commonly brake disc.

[Dave80GTSi]

Update: Refining my earlier search to "Girodisc", this thread now pops up.

Link posted here for reference (mostly starting at Post #15):

2004 S for trackdays and anydays

[mikefocke]

Maybe
http://www.boxa.net/forum/topic/76068-photoshop-favour-please/?tab=comments#comment-979231

[Dave80GTSi]

Originally Posted by mikefocke

Maybe
http://www.boxa.net/forum/topic/76068-photoshop-favour-please/?tab=comments#comment-979231

"You do not have permission to view this content".

Can someone who does "have their permission" please post the referenced info here?

Thanks - DM

[edc]

Register and you can see it no problem.

[edc]

http://www.boxa.net/forum/topic/64062-roxster-gt3-aka-molly/?page=4&tab=comments#comment-794043

[Dave80GTSi]

Originally Posted by edc

http://www.boxa.net/forum/topic/64062-roxster-gt3-aka-molly/?page=4&tab=comments#comment-794043

Got it, thanks! I was simply resisting the need to register for yet another on-line forum. I seem to have enough trouble remembering the various existing user names and passwords already!

In any case, 250-ish Sterling as noted in the above thread is much more like what I was hoping to find!

I have sent an inquiry over to FreakyParts, and will post here their reply, if there is any interest expressed in the meantime.

Thanks and Cheers to all for the kind assistance - DM

[Dave80GTSi]

Have heard back - Note that I am passing this info onwards simply as a FYI; I have no affiliation.

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Sorry for the delay in getting back to you, it took a little time to dig out the information. We last made the kit in 2015!
In answer to your question, yes, we make a larger disc conversion for the 318mm front disc setup.
We can supply the kit, which comes with:
1x pair of 338x28mm plain/grooved/dimpled/drilled, black/silver/gold antirust coated discs
1x pair of custom caliper adaptors
1x set of longer bolts
1x pair of spigot rings for the discs

The total price for this kit would be £289.00 plus shipping.

If you'd like to order the kit, can you send the payment via PayPal to sales@freakyparts.co.uk (as friends/family or covering the fees) and follow it with an email to the same address with the order details and delivery address and I'll get a kit sorted for you.

I've attached a picture of the kit as fitted to a previous customers car.
thanks
Stewart
FreakyParts

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Seems like a very cost-effective upgrade, particularly for anyone who is due for a pair of new front rotors anyway.