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Hi all,

Upgrading the rotors in the std 32 gtr callipers, and i see the std rotors are front - 296x32mm and rear - 297x18mm.

What is the maximum thickness rotor i can fit in the stock callipers, front and rear.

cheers

Shane

That is a really odd question.

32mm is what they come from the factory new. I guess you could go wider than that is you ran old pads, but....

By way of comparo the V8 Sillycars run rotors that are 375x25mm. So you can see the Nissan stuff is small in diameter & quite fat.

A number of aftermarket rotors can be had in either 1 1/8" & 1 1/4", ie 28 or 32mm.

That is a really odd question.

32mm is what they come from the factory new. I guess you could go wider than that is you ran old pads, but....

By way of comparo the V8 Sillycars run rotors that are 375x25mm. So you can see the Nissan stuff is small in diameter & quite fat.

A number of aftermarket rotors can be had in either 1 1/8" & 1 1/4", ie 28 or 32mm.

reason i ask, is i'm looking at a larger dia rotor for the front and rear from stoptech, and they have varying thickness rotors. however the smallest being 22mm and go upto 35mm.

i was under the impression, the thicker the rotor the better, as it aids in heat dissipation?

Well sort of, not really, it depends.

If you are buying a new rotor why not just get the 32mm width?

There are a number of elements as to cooling. One of the most important, yet most neglected, is the number of cooling vanes internal to the rotor. These effectively work like a fan and pump air through the rotor. The more vanes the more airflow. So it might be an idea to ask C-Red (Stoptech agent?) how many the things have.

Well sort of, not really, it depends.

If you are buying a new rotor why not just get the 32mm width?

There are a number of elements as to cooling. One of the most important, yet most neglected, is the number of cooling vanes internal to the rotor. These effectively work like a fan and pump air through the rotor. The more vanes the more airflow. So it might be an idea to ask C-Red (Stoptech agent?) how many the things have.

ok, that's the fronts sorted, but im still not sure about the rears if i can run the 22mm ones or if i can only run 18mm ones.

Regarding airflow, it seems they have designed for this fairly well, as they show here https://www.stoptech.com/products/BBK/best_...r_airflow.shtml.

i was looking at a 355mm rotor at the front, and need to replace the rear so thought why not upgrade it aswell. keeping in mind these will be pulling up a ~750bph gtr on semi's :worship:

Well it is just money at the end of the day. It won't cost alot to try the new fronts with the current rears.

You may well find if you are pulling up a full weight GT-R with that kind of hp the pad size in the standard Sumitomo calipers or even the Brembo's is far too small. It would be worth your while to check on the pad sizes offered by Stoptech in their calipers. They seem to have some fairly large offerings.

how are you planning to fit these? you realise you cannot just pull off your old rotor, and whack on some 355s... you will either need new calipers (would strongly reccomend it for 355s) or at the least a custom made bracket to offset the caliper. bear in mind you will need some 18s to fit this under. with a 750hp track car I would bin all the factory gear and start again with something bigger and better.

Well it is just money at the end of the day. It won't cost alot to try the new fronts with the current rears.

You may well find if you are pulling up a full weight GT-R with that kind of hp the pad size in the standard Sumitomo calipers or even the Brembo's is far too small. It would be worth your while to check on the pad sizes offered by Stoptech in their calipers. They seem to have some fairly large offerings

hmm thats food for thought. i'll drop stoptech an email and see what they have to offer for mounting hardware and interchangability

i'm hoping to be at the nsw track day in july, so just need something that will perform safely and i doubt the stocko's will do it too well.

how are you planning to fit these? you realise you cannot just pull off your old rotor, and whack on some 355s... you will either need new calipers (would strongly reccomend it for 355s) or at the least a custom made bracket to offset the caliper. bear in mind you will need some 18s to fit this under. with a 750hp track car I would bin all the factory gear and start again with something bigger and better.

yep i definately realise i'll need some custom brackets. and i have a set of 18" TE37's

dammit, looks like i'll have to trial fit the rears for myself :D

cheers for the input and help guys, greatly appreciated :worship:

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