[justpete]

Originally Posted by NiNeTyOne

You did make the front rotors a bit bigger though yes? The 135i setup as I recall is the same as the BMW Performance brake setup which is 338mm front with 300mm rear rotors, what size rear rotors did you go with?

Front rotors are RB replacements for stock 135i front rotors. Rear rotors are e46 M3 CSL which is 328x20, close enough to the 135i rear rotor to use the 135i rear caliper with a 5mm spacer.

Originally Posted by NiNeTyOne

I'm also curious how thick the RB rotors are. I tried them a few years back on the race car and I had issues cracking rotors with them. I ended up going back to Brembo rotors and hats. The Brembo hardware also may have resolved your pad clearance issue, but not 100% sure of that. The folks at Race technologies could answer that.

28mm, iirc. Pretty sure they won't be an issue on this car. Will be keeping an eye on them and replacing them regularly. Pad clearance solved by welding up and then grinding to fit on the bracket to gain radial spacing.

Originally Posted by NiNeTyOne

I also noticed you took the vibration dampers off the front calipers. Curious why?

Not seeing the reason for them to be there and it cuts unsprung weight. Can always reinstall them if removal's a problem.

Originally Posted by NiNeTyOne

Would love to know where you sourced that Samco coolant hose kit. I had those on the S4 for all my coolant, boost and intake hoses that weren't solid and they were great. I used Oetiker clamps instead of hose clamps, that's very much the way forward.

Those are the first set made, for me. Samco supplied some better than usual hose clamps so we'll use them in place of the stock Oetiker clamps. Should be fine, I think.

[NiNeTyOne]

Originally Posted by justpete

Those are the first set made, for me. Samco supplied some better than usual hose clamps so we'll use them in place of the stock Oetiker clamps. Should be fine, I think.

I'd be interested in a set, let me know how they fit when you put them in.

Not sure how heavier you are, my 440AWHP track car was 3310# wet with me in it and 32mm thick rotors at that weight to have enough thermal capacity to not get away from me. I had really good custom ducting as well with custom carbon shields on the back of the rotor that forced all the air into the hub for maximum cooling. I had two ducts in the bumper and two naca ducts in the belly pan to pick up cool air and get it to the brakes.

I also ran Pagid pads but found the 29's too grabby and abrupt on release, but the 19 is the same temp range and had very nice pedal feel. Used them on the Porsche race car as well and liked them. Used 42's in the rain and 14's when it got really hot out and the 19's would fade (Sonoma, Willows). The endurance pads are great, but they do not generate the same high friction coefficient the 19/14's do.

If you use backing plates on the pads, have them ceramic coated, it'll help keep the fluid in the calipers cool. I ultimately had my calipers coated in thermal dispersant and it made loads of difference.

[justpete]

Originally Posted by NiNeTyOne

I'd be interested in a set, let me know how they fit when you put them in.

Not sure how heavier you are, my 440AWHP track car was 3310# wet with me in it and 32mm thick rotors at that weight to have enough thermal capacity to not get away from me. I had really good custom ducting as well with custom carbon shields on the back of the rotor that forced all the air into the hub for maximum cooling. I had two ducts in the bumper and two naca ducts in the belly pan to pick up cool air and get it to the brakes.

I also ran Pagid pads but found the 29's too grabby and abrupt on release, but the 19 is the same temp range and had very nice pedal feel. Used them on the Porsche race car as well and liked them. Used 42's in the rain and 14's when it got really hot out and the 19's would fade (Sonoma, Willows). The endurance pads are great, but they do not generate the same high friction coefficient the 19/14's do.

If you use backing plates on the pads, have them ceramic coated, it'll help keep the fluid in the calipers cool. I ultimately had my calipers coated in thermal dispersant and it made loads of difference.

Should have install photos from the shop this coming week, will post them.

My car is about four hundred pounds lighter with me in it but only about 280rwhp so far. Thermal capacity should be plenty overkill. Rotor is too wide for the Hard Brake plates I already have, might reinstall them as the pads wear. Torque fluid should be ok with what little heat a momentum car will generate, I think. We'll see with the pad release characteristics on my car, not really critical as I'm not that good a driver yet to where it will matter much.

[NiNeTyOne]

Originally Posted by justpete

Should have install photos from the shop this coming week, will post them.

My car is about four hundred pounds lighter with me in it but only about 280rwhp so far. Thermal capacity should be plenty overkill. Rotor is too wide for the Hard Brake plates I already have, might reinstall them as the pads wear. Torque fluid should be ok with what little heat a momentum car will generate, I think. We'll see with the pad release characteristics on my car, not really critical as I'm not that good a driver yet to where it will matter much.

You'll appreciate the release when you miss your braking point and have to trail deep into a corner. When you release the chassis will stay composed and you want be all hairball mid-corner.

I shaved my pads AFTER bedding them, as you really want to shave them once all the binder has been cooked off. That gets you some room and insures you don't drag you pads.

Are you running with or without the dust seals? That will help, but you can plan on rebuilding the calipers frequently.

You'll like the torque fluid. Be prepared to bleed a little bit every day or even after a really hot session. It's amazing fluid but it still needs the usual care and feeding.

I installed speed bleeder valves in the calipers and it makes VERY fast work of a four wheel bleed track-side, like less than 5 min to do all four wheels.

Speed bleeders

[justpete]

Originally Posted by NiNeTyOne

You'll appreciate the release when you miss your braking point and have to trail deep into a corner. When you release the chassis will stay composed and you want be all hairball mid-corner.

I shaved my pads AFTER bedding them, as you really want to shave them once all the binder has been cooked off. That gets you some room and insures you don't drag you pads.

Are you running with or without the dust seals? That will help, but you can plan on rebuilding the calipers frequently.

You'll like the torque fluid. Be prepared to bleed a little bit every day or even after a really hot session. It's amazing fluid but it still needs the usual care and feeding.

I installed speed bleeder valves in the calipers and it makes VERY fast work of a four wheel bleed track-side, like less than 5 min to do all four wheels.

Speed bleeders

Hairball mid-corner is my jam...

Come to think of it I've no clue what thread the bleeders are on the calipers.

The front calipers are rebuilt with Stoptech pistons, boots, and seals.

[NiNeTyOne]

Originally Posted by justpete

Hairball mid-corner is my jam...

Come to think of it I've no clue what thread the bleeders are on the calipers.

The front calipers are rebuilt with Stoptech pistons, boots, and seals.

Those are good seals and pistons; did you get them from Dave Z?

You can also ceramic coat the inside of the pistons and the piston faces if it gets to be an issue. That's a cheap and easy proposition when you're doing a rebuild and it helps quite a bit to keep the fluid from getting cooked in the caliper.

[justpete]

Originally Posted by NiNeTyOne

Those are good seals and pistons; did you get them from Dave Z?

You can also ceramic coat the inside of the pistons and the piston faces if it gets to be an issue. That's a cheap and easy proposition when you're doing a rebuild and it helps quite a bit to keep the fluid from getting cooked in the caliper.

Turner Motorsport.

Will be very concerned if this momentum car ever puts that much thermal load on the brakes.

[NiNeTyOne]

Originally Posted by justpete

Turner Motorsport.

Will be very concerned if this momentum car ever puts that much thermal load on the brakes.

I've been in a lot of "light" cars you may consider momentum cars, Spec E30's, Spec Miata's.. brakes are always a factor. Much more so than people want to admit, typically because real brake systems are real expensive

[justpete]

Originally Posted by NiNeTyOne

I've been in a lot of "light" cars you may consider momentum cars, Spec E30's, Spec Miata's.. brakes are always a factor. Much more so than people want to admit, typically because real brake systems are real expensive

Well sure but physics determines thermal loading of the brakes and a lighter lower power car doesn't need massive rotors to manage fade. Been working just fine so far with zero fade.

[NiNeTyOne]

Originally Posted by justpete

Well sure but physics determines thermal loading of the brakes and a lighter lower power car doesn't need massive rotors to manage fade. Been working just fine so far with zero fade.

Well aware, I have a BS in physics

You're making all manner of claims without any mention of which circuits you are running, all while saying you don't have a lot of experience on track..???

Not buying your optimism. I was spec'ing brake systems for GP teams at Jerez 17 years ago. I kinda know what I'm talking about here.

[justpete]

Originally Posted by NiNeTyOne

Well aware, I have a BS in physics

You're making all manner of claims without any mention of which circuits you are running, all while saying you don't have a lot of experience on track..???

Not buying your optimism. I was spec'ing brake systems for GP teams at Jerez 17 years ago. I kinda know what I'm talking about here.

Same here.

Don't care if you don't buy it, this is a pointless internet forum, please do enjoy yourself taking it all so seriously. Personally, I don't give a shit, I have a life.

[NiNeTyOne]

Originally Posted by justpete

Same here.

I'll just go grab some popcorn then.. I haven't had a good show in a while.

[NiNeTyOne]

Originally Posted by BudVlad

Let us know what you did with the brake calipers. I was wandering why Brembo added unsprung weight and if I can cut it off.

Those are bolt in harmonic dampeners. They are there to reduce the harmonics at brake application.

Most running these calipers find them too narrow to accommodate sufficiently large (as in thick enough) rotors, even on the 135's to deal with regular track day abuse once they get on pace. The 26 or 28mm rotors that fit in these are not adequate. Most end up with 32mm thick rotors.

Many learn the hard way when the brake fluid boils out of the reservoir causing total brake failure. That's always a fun moment.

By comparison, my last non-race car that saw track duty was only a couple hundred lbs heavier and had 355x32mm fronts and 330x30 rear, and it was under braked.

[justpete]

The ATI damper test fit plug fits perfectly so now it's just down to the mfg leadtime before it's available. No idea how long this will take, haven't been able to get an answer. FYI

[justpete]

Samco Sport coolant hose installation



The end of the CAI is visible in the airbox

[justpete]

FWIW the N54 test fit plug worked out so mfg for both the N52 and N54 dampers can proceed. Supposed to get a leadtime soon.

[Taskmaster]

Any video of the car in action?

[justpete]

Originally Posted by TheAxiom

Any video of the car in action?

Hell, I haven't even seen it in a couple of months... :/

[Taskmaster]

Originally Posted by justpete

Hell, I haven't even seen it in a couple of months... :/

Soon - SOON! I have hope! I just meant from any of the previous track days.

[justpete]

Originally Posted by TheAxiom

Soon - SOON! I have hope! I just meant from any of the previous track days.

ha

Yeah, me too. Most days anyway...

Got a couple videos but they're not that interesting and I'm pretty sure one of them's been posted at least once before, somewhere on the forum...

[Taskmaster]

Originally Posted by justpete

ha

Yeah, me too. Most days anyway...

Got a couple videos but they're not that interesting and I'm pretty sure one of them's been posted at least once before, somewhere on the forum...

I swore I saw one, and I've been looking around...

[justpete]

Originally Posted by TheAxiom

I swore I saw one, and I've been looking around...

Yep, you did, I found it but I deleted my Vimeo account so it's no longer accessible.