Most liked posts in thread: The Phoenix - The GP Roadster Project

Transmogrification Step 13 - Moar Stopping!

I replaced my stock 1st gen front calipers and rotors with 2nd gen MCS calipers / rotors a few years ago - a great mod. The stock 1st gen brakes are CRAP... at least for hard driving and the track. As most of you know, the 2nd gen MCS front brakes are the same as the 1st gen JCW brakes, just without the red powder coat.

But I've still been running on the stock 1st gen rear calipers for 150k miles now. Many pad and rotor swaps, and installed the bronze bushings several years ago. But otherwise still living with their crappiness. The rears don't do nearly as much work as the fronts... but they don't have the improved lubricated guide pin design and pad design of the 2nd gen brakes, and tend to drag more (especially if you're not diligent in lubing the bronze bushings).

Since I'm going to go even more aggressive on the front (stay Tuned), I decided to go to the 2nd gen JCW rears if I could find a set... and I did. These use a 280mm rotor vs. a 259mm rotor for the 1st and 2nd gen MCS brakes. Other things being equal, larger rotor equals more stopping torque and less heat. I'll be running more aggressive pad compounds on the front, and can fine-tune brake bias by changing rear compound friction as needed.

Plus the bigger rear rotors just look a lot better...

Here's the stuff:

• 2nd gen JCW rear calipers (came with OEM pads that still have some life in them, I have Carbotech XP8's on the way)
• SP Performance T06-420 rotors
• 2nd gen OEM parking brake cables

I was also going to swap my rear wheel bearings as PM while I was at it... but someone in Germany put front wheel bearings into rear wheel bearing boxes. Doh. Oh well, my bearings are still fine for now.

The 2nd gen brakes are designed to work with the alloy trailing arms, and have the brake line and parking brake cable in different positions than the 1st gen. Which happen to interfere with the 1st gen steel trailing arms. So some grinding on the trailing arms is required to make clearance. I had a good carbide bit for my die grinder, was no big deal. I plan to do the alloy trailing arms retrofit at some point in the future...

The 2nd gen brakes also have a different fitting for the end of the Bowden cable housing, so you need 2nd gen parking brake cables. The cables themselves are plug and play, but require some disassembly of the brake handle console and exhaust heat shields to get done. There are instructions around for how to do it... search is your friend.

Old vs. new. You can see that the JCW rotors are almost an inch larger:


Before:


After:


And yes, they look goooood with the wheels on. :cornut:


Taking a break now, will be later today before I drive it. I don't expect any real improvement, except perhaps at the track and in the mountains. And in lower maintenance and more reliability for the calipers.

 

Transmogrification Step 13b - Moar Stopping (part 2)

I've been running 2nd Gen MCS brakes on the front for a few years... a huge upgrade from the 1st gen stock brakes. But even with these, and with great pads, I've had overheating issues in the past. So tonight I went from this:


to this:


I know not everyone is in love with these calipers - I get that, but everything's always a trade-off of some kind. I want to stick with my 16" wheels, so my options are limited. I don't want to spend a zillion dollars, so that limits them some more. I want to focus on heat management, which means fat directionally vented rotors. In the world of fat rotor kits for Minis that fit in a 16" wheel, you don't have a lot of options.

Oh yeah, and it had to be RED. :lol:

So here's what really sold me on this kit:

On top, 2nd gen MCS (1st gen JCW) rotor. On bottom, DT rotor. It's massive.

The diameter of them is almost identical, even though the DT looks bigger in this pic, if you stack them, they're within a couple mm


But the vastly superior venting has got to do something good...


The "business end" of the airflow... this has got to move air better than the OEM rotor.


Interestingly, the calipers use pads with LESS contact area than the old calipers:

New XP10 pad for these calipers on the left, XP12 pad for my old calipers on the right. And they use thinner pads, with less friction material than the OEM calipers. Another trade-off. But at least these CT pads don't have rivets, so I can run them down thinner (in theory).

Will be interesting to see what kind of life I get on pads and rotors. I upgraded to the cryo-treated rotors, in the hope that they'll last longer. We'll see. Cooler setup should mean that I'm able to stay within the XP10 temperature range, and get longer pad life. Again, time will tell.

Took it out for a test drive... OMG STOPPING. I really didn't expect a night and day difference. The pedal feel is much more firm and the pedal is a bit higher - a welcome surprise. With the ZII's it took some serious brake application to get into the ABS with the old brakes... once warmed up, the XP10's and these brakes are like an anchor... I think I could almost do a front wheelie. And it takes a lot less effort to get to the limit of the tires and invoke the ABS. It's not touchy... there's just a lot more available clamping force there. Should be plenty for later when I move up to R888's or Rcomps. Modulation is still very good. Bias with the rears also seemed good once everything was warmed up. Really really happy right now. We'll see how they do at the track in a few weeks.

 

The Transformer is going to put it all back together, when I fail. And the vampire is gonna punish me for thinking I could DIY.

 

Picking this thread back up.

If you followed the Auto DIY Rebuild thread, you know that was a FAIL. But my engine is running great!

I'm working right now to secure a donor car to do a major organ transplant, to convert Blimey to MANUAL. Parts start arriving tomorrow, and hopefully I'll win an auction on a donor car tomorrow.

Then the fun continues

 

Well, this happened.


Getting proficient at something I never really wanted to be proficient in. Oh well.
Took about half as much time to pull the engine as it did the first time.

Tomorrow, work on the engines, and strip the engine bay for painting.

 

Nope. Like I said before - before MOTD 2016. That's next year.

This year, it will be Frankensteined. Which is cool.

At least ONE car with mismatched panels will be at MOTD this year. :devil:

 

After fiddling with NCS Expert some more, I drove another 40 miles on Monday.

This happened:



What do you NOT see?

Warning lights. Win.
(of course, the airbag light has tape covering it... shhhhh)

On Sunday, I eventually swapped in the steering angle sensor from the GP, and reset all the DSC sensors individually with AutoEnginuity. This seems to have cured my DSC faults. Perhaps just resetting the sensors would have done the trick, but I've read some places that the steering sensor gets initialized to the car / VIN...

However, I did discover that my Xenons and Cruise weren't quite working right. And my convertible "windows down" button wasn't putting all four windows down, only the rears.

<WARNING GEEKY ARCANE CODING STUFF>
On Sunday morning, first thing, I started working on coding with NCS Expert. It had been a year since I had touched it and had to re-learn how to do it. I accidentally did a "process car" using the GP's VIN and a blank .MAN file. As a few folks may know, doing this resets ALL modules on the car to the factory defaults, based on the options installed on the car. In this case, the options installed on the GP at the factory. So, it thought it had too many airbags, no convertible top, halogen headlights, etc. Completely negating the value of me keeping the original BC1 from the cabrio. Oops.

After fighting with NCS Expert, attempting to get everything sorted back out on the BC1 and ABG modules, I decided to attempt to recode them back to the original cabrio defaults. I unplugged the GP EWS (immobilizer) module, and plugged in the one from the cabrio. Left everything else the same. Then ran NCS Expert and fetched the VIN and options list from the EWS, and did a "process ECU" using blank .MAN file on the BC1 and ABG modules. Tested lights and convertible window switch - ALL GOOD. Checked airbag settings. Now it's looking for the right combination of bags. Then swapped back to the GP EWS, tested again, and recoded my desired options (e.g. comfort opening / closing with the key). Done.
</GEEKINESS>

Also got this in the mail:


Matches my e-brake handle and steering wheel. Awesome.

Came with a cheat sheet. :lol:


After I stopped laughing, I realized I might be the only MINI driver in the world who actually needs that. So, installed.


As long as I don't ever need to find "R" on the racetrack, I'm good. :devil:

 

Thanks Chris.

I have the car I want, running well. That's enough of a reward.

That, and bragging rights. And people tilting their heads when they see it at MOTD. :cornut:

 

Crank sensor replaced and tested. Car put back together completely with all braces and bumper hardware for the first time in 7+ months.

Went for a drive, threw a P2270 code. First time I've ever had that one. Post-cat O2 sensor stuck lean. Which in my car means the O2 sim isn't working. Pulled the O2 sensor, and yep, crappy solder job had broken loose. Fixed a million percent better, won't break again. Reinstalled. About to drive some more.