May be some one can confirm please

I understand that the 6 piston OEM Brembo front calipers on a stock GP2 are the same as the ones that came stock on a BMW 135 ( the grey ones )

So am I to be correct in thinking that the BMW performance BBK. that was offered for BMW 128's ( the yellow ones ) would fit a GP2 ? I'm guessing I would need that caliper brackets or are they the same also ? What is the rotor diameter of the GP2 OEM rotor?

For clarification the pics below are the set of calipers in question. I removed theses off my 128 before turning her back in. . I planned on selling them but maybe not ? I have a fR58 JCW so it may be a cool upgrade if I feel the OEM JCW calipers can't hold up to next years 10 track days.

I wonder if the backing plates are the same ?

Thanks in advance for any input.













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Buller ?

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Visually, they do look very similar (if not identical), however, you'd need to source the brackets to mount the caliper to the front hub. I doubt the brackets you have from the 128 fitment will work on the R58.

 

The calipers are the same. Pads are the same.

The hubs are different, the minis are 4 bolt pattern and 1 series are 5 bolt pattern. The rotors are different sizes as well.

If you were going to use these the easiest way would be to buy oem GP2 rotors.

 

Thanks guys.

Duh. I didn't even think about the spindles/hubs. Of course they are different.

Ok so caliper brackets , rotors, and backing plates it is to convert shouldn't be any problem to source those as they are all OEM.

I know 135 owners had issues with the 6 piston Brembo caliper pistons crumbling. We had a big discussion in the 1addicts forum on this and determined that the heat generated on the track with the higher speeds and weight of the car were the culprit. Those calipers pictured above have 3 seasons of track days. That's approx 30-35 events ( 5 / 25 to 30 minutes sessions per day ) and I had zero issues ever. Not even fade. I had done some mods to help. Titanium heat shields / f30 backing plats with larger built in cooling duct / high temp fluid / good pads / flushes .

The 135 had 20 to 25 mph top speed on me on the straights so there is the speed and the 135 weighed about 300 lbs more ( turbos, sunroof, lux accessories wheels )

I've read here that the gp2 guys were having issues also. Seeing that the weights of a cooper and 128 are close I have to imagine it's all about the cooling and the heat control ( titanium shields ) I can't imagine that the gp2 can achieve that level of heat ? But I guess it does. One would think that the big rotor was a sufficient heat sink but it appears not.

I wonder if I could modify those f30 backing plates. I really believe they made a difference. Installing full brake ducts on a DD insane.

My mock up of my first attempt of a backing plate with a cooling duct









Then I found the f30 plates with theses built in from BMW and it was an easy mod to get them to fit. Just move a mounting hole.
I think you can see them in the pics in the first post.

The 128 in question. She was fun to track. The heated seats were great early and late in the season





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IF the calipers are actually the same between the 135 and the GP2 then you need caliper brackets, rotors, backing plates, and maybe brake lines from a GP2. They "should" bolt right up. I don't see the bracket as a separate part # from the caliper though so that may cause you some problems.

I can't imagine you'll have issues with brake fade on the track with the mini. What tires are you running? Which brake pads?

 

Hmmm I see what you mean. No separate part for the brackets. I'll have to do some research.

I haven't run the mini yet on track. I only recently got it and my club EMRA only had 2 more events. I'm prepping for next season ( I'm in NY so it's seasonal)

I ran ferrodo 2500's and RS'3 on the 128. I don't think I can get the size I want for the RS3 for mini fittment although I have stock suspension witch I prefer as it's a little mor forgiving on the curbing and suites my driving style. The pads I'll choose are still up in the air. I don't mind swapping pads at the track but sometimes it could be a pain.

I learned ( although not mastered ) " slow in fast out" along with some other things that won me a season in my class and 3 rd in another season so I'm happy with that. As long as the car stays together and stays shiny side up I'm good.

I did learn I need a harness bar for the track. I've had corner workers catch me in the pits and say " your fast but you need to control your head, im leaning way to far to the point at which they see my helmet go side to side. Constructive criticism is a good thing.

I think the JCW calipers will Ben fine. I'll just pick the correct pad.

Thanks for the input

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In fact if you look at ECS Tuning's website you can see the part numbers clearly on the brackets.

http://www.ecstuning.com/ES2643016/

Scroll through the images.

Brembo caliper bracket part # 20.9747.85
Seals for the pistons part # 20.4872.40

 

GP2's have a specific Booster as well, just fyi...