280 to 300mm disc options

[Rob7655]

Last year I fitted brembo callipers using the pms kit, I've decided to go to 300mm discs but I didn't realise I'd need a different mounting kit.

Is there any other options before I pay nearly £200 for the pms brackets?

Thanks

 

[Rob7655]

Or has anyone got a 300 mounting kit for sale?

thanks

 

[Rob7655]

 

[MLB]

Or has anyone got a 300 mounting kit for sale?

thanks

I will have to have a look but yes I think I do have a 300mm kit!

 

[Clio_fool]

Did pms machine the calipers for you? Iirc they machine a counterbore in the caliper, how much flat mounting face is left after that? Pms we're the only ones making the 280 brackets like that so any 300 bracket you find won't sit in the counterbores and you may have minimal face to face seating.

 

[Rob7655]

Hmmm, I bought the car with the calipers in the boot, the 280 kit fits no problem,

 

[Clio_fool]

Is it this kit? https://www.pure-motorsport.co.uk/brembo-280mm-brake-bracket-kit.html

 

[Rob7655]

Is it this kit? https://www.pure-motorsport.co.uk/brembo-280mm-brake-bracket-kit.html

Yes , I purchased the kit direct.

 

[Louis]

Hmmm, I bought the car with the calipers in the boot, the 280 kit fits no problem,

They must have been machined though?

 

[Clio_fool]

So your calipers would have been machined like this to fit the brackets.

Every other 280 kit the caliper mounting face is just machined down by 5mm but now you've not got much flat face to bolt the 300 brackets to.
This is the face -5mm.

And the bracket on.

And these are brackets for 300mm discs on the car.

 

[Louis]

Wonder if you could just make some turned spacer adaptors to extend them further out.

Little top hat stylee

 

[Clio_fool]

Wonder if you could just make some turned spacer adaptors to extend them further out.

Little top hat stylee

You'd need to space them out 10mm and the bores are only 11 deep so you could only do it with a big washer and then location is by the bolt and it's still sat on what's left ot the caliper mounting face.
Best thing to do is stick with 280 discs or sell the calipers and brackets and buy new for 300 discs.

 

[Rob7655]

They must have been machined though?

They must have been, thinking back the brackets were on the calipers I just had to order the bolts from pms!

 

[Rob7655]

Ohhh, thanks for explaining that! Looks like i better have a re think.

 

[MLB]

What's the reason that you want to go to 300mm discs?

I've not noticed any difference with mine on track between 300 and 280mm discs.

If anything with 280mm discs you have a greater choice of wheels that fit. 300mm was a right pain because of wheel balancing weights touching the calipers.

 

[Louis]

You'd need to space them out 10mm and the bores are only 11 deep so you could only do it with a big washer and then location is by the bolt and it's still sat on what's left ot the caliper mounting face.
Best thing to do is stick with 280 discs or sell the calipers and brackets and buy new for 300 discs

Let me draw what I'm thinking

 

[Rob7655]

So basically my callipers have had to much machined off.

 

[MLB]

Let me draw what I'm thinking

This can go wrong in so many ways.

 

[Clio_fool]

So basically my callipers have had to much machined off.

No. The pms brackets don't remove any material off the face as the bracket fits into the counterbore machined into the caliper. It's all to do with thread depth on the bracket, some noobs on Facebook made some that sit on the caliper face and the bolt screws into the bracket but you only had 5mm of thread depth which equates to 3 threads holding your brake caliper on, not good. The pms way gives more thread depth in the bracket. I fitted studs to the ones I made and had a nut on top of the caliper instead.

 

[Rob7655]

No. The pms brackets don't remove any material off the face as the bracket fits into the counterbore machined into the caliper. It's all to do with thread depth on the bracket, some noobs on Facebook made some that sit on the caliper face and the bolt screws into the bracket but you only had 5mm of thread depth which equates to 3 threads holding your brake caliper on, not good. The pms way gives more thread depth in the bracket. I fitted studs to the ones I made and had a nut on top of the caliper instead.
View attachment 1773447

 

[Rob7655]

I see, thanks

 

[Rob7655]

What's the reason that you want to go to 300mm discs?

I've not noticed any difference with mine on track between 300 and 280mm discs.

If anything with 280mm discs you have a greater choice of wheels that fit. 300mm was a right pain because of wheel balancing weights touching the calipers.

What's the reason that you want to go to 300mm discs?

I've not noticed any difference with mine on track between 300 and 280mm discs.

If anything with 280mm discs you have a greater choice of wheels that fit. 300mm was a right pain because of wheel balancing weights touching the calipers.

Looks and I wanted new discs while I refresh the front end with drive shafts bushes etc

 

[MLB]

It does look pretty good, I'll admit that!

 

[Clio_fool]

Yep they do look cool. What wheels are you running @Rob7655 ? Disc size won't make much difference with standard 182 wheels. Unfortunately I don't have a decent pic of mine with the Turini's on.

 

[Rob7655]

 

[Rob7655]

247 bhp quaife diff lots of good bits on it,

 

[Clio_fool]

That's sexy. Silver wheels for the win, personally I don't think it needs the bigger discs.

 

[Rob7655]

Thanks, if it means buying new calipers and brackets it won't be getting the 300,s..... shame I've bought discs already though.....oh well😆

 

[MLB]

That looks soo clean! Great combo with the silver wheels 👌

 

[TheBandit]

300 looks great but as mentioned 280 would make life easier. I have 3mm between calliper and wheel and stuck using 16's. I bought the car with, but if I was doing it again I would go 280 for greater wheel selection.

 

[Speedo Gonzales]

It depends which 280mm PMS kit you've got

I'm sure the early ones had more machined off the caliper and a thinner bracket that was a bit more susceptible to breaking

If it's the later one, as people have said you'll be better off sticking with 280mm discs or selling and buying the 300mm setup

I've got a set of Osspoop 280mm brackets. I genuinely don't think there's any point in going to a 300mm setup unless you like buying more expensive 16" tyres🤣

Even 280mm are tight under 15" Speedlines with BYC brake ducts

 

[Clio_fool]

I actually saw a pair of mine for sale recently and they've held up very well considering I made them in 2019 😯.

Just realised they are the aluminium ones too!

 

[Louis]

I actually saw a pair of mine for sale recently and they've held up very well considering I made them in 2019 😯.
View attachment 1773493

Just realised they are the aluminium ones too!

Mine held up great but I did paint them too. Best brackets

 

[Clio_fool]

Mine held up great but I did paint them too. Best brackets

They were steel and zinc plated so should have lasted. Remember those other ali ones that crumbled to dust? 😱