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Quotes from the GTT Spiroslot Official Thread

I initially had some problems with a third-party installation of my GTT Spiroslots. :eek: Although all of this is detailed in the GTT Spiroslots Official Thread...

...I've hooked out the relevant posts from my own experiences for you. Here's a list of things people gave me to check:

OK, so the updated list is:
  • Clean the sliders that the pads move across/sit in.
  • Copper slip/grease on the pad face (the part that touches the calliper - not the part that touches the disc!)
  • Clean and file the hub mating surface with the disc to ensure the disc rotates true to the calliper.
  • Check that the spring wire on the backface of the inboard rear pads is clipped into the groove in the piston at all three points to ensure it's square onto the disc.
And hopefully that should rectify things... :D I'll try to get it sorted this weekend - just need to find somewhere reasonably close that I can book it into.

Many thanks,

After I had it in to an alternate Scotland-based tuner, most of the problems went away, and then the installation was finally put 'right' when I managed to get down to see Roland in person and my brake fluid was uprated:

Hello - I thought it time I made an update in here. A family visit to the south of England finally made it possible for me to take the car in to GTT and, I can quite happily say that:
My GTT Spiroslots are fantastic and problem-free!!
Roland drove me out in my car and demonstrated a few emergency stops and things to look out for when checking the brakes for problems. Amongst other things, I got a lesson on driving with high performance brakes - the trick is to be a bit more relaxed when applying them, and actively control the car to a stop rather than just gripping the wheel straight and throwing out the anchor. ;) Thanks Roland! :D

As for my callipers, Roland knew exactly which rubber seals the other garage here in Scotland had been referring to and it's not problematic as they had made it out to be. :) So that's not really something I need to worry about.

And finally, my braking fluid was uprated to 5.1 - this makes a heck of a difference!!! The winding country road on the way home consists of some very straight national speed-limit bits interspersed by some 90 degree corners. Previously, when I'd use the brakes heavily and repeatedly on these sections, by the time I got to the end of the road, my brake pedal was all spongy and would sometimes sink further than normal on the last corners. A few pumps would make this problem go away but after it happened the first time, I never quite felt the brakes had the same feel as before. Now that Roland has uprated the brake fluid, the feel of the brakes is much more solid and extremely consistent - regardless of how many applications.

Anyway, as aforementioned in the post above, I'm not experiencing squeal when the brakes are not in use (this was due to an incorrect initial installation in Scotland). Also, now that a few more hundred miles have been put on the pads and discs they seem to have settled in even better than before: the low-speed squeal I sometimes get around town areas (while never quite fully disappears) is now dramatically reduced. One thing I noticed is that it rarely did it whilst I was down south (nice warm weather) so I think the brisk climate of Scotland might have something to do with it. :confused: After a spirited drive and the brakes are warmed up (well, hot - with the way I sometimes use them ;)), they're virtually silent. :D

Concluding thoughts:
The added stopping ability the GTT Spiroslots add to my MINI is phenomenal! I highly recommend them - but with one note of caution: get them fitted by GTT themselves so that you're absolutely sure they've been competently installed. If I'd done this initially, I would have avoided all the problems I've experienced with the initial incorrect installation of the Spiroslots.

And that basically concludes my review. :) Any questions? :confused: :D

All the best,

And this is almost a reiteration, but was trying to clarify some points in the above post:

At the risk of reiterating my earlier post... :p

All the problems I had stemmed from the very first installation of them (independent mechanic in Glasgow) - the mating surfaces on the hub weren't cleaned, the sliders weren't oiled, and insufficient quantities of copper slip were used. I found the dramatic weaving from side-to-side under heavy braking was down to the mating surfaces. Brake noise when not actually applying the brakes was due to unoiled sliders and insufficient copper slip on the back of the pads.

On re-installation (tuner based in Glasgow) all this was done and it dramatically improved things - however, I still wasn't altogether confident... I was experiencing what I thought at first was brake fade, but in retrospect I think I was boiling the standard brake fluid. :eek:

When I finally was able to take the car to GTT I had the brake fluid changed and the Spiroslot installation checked. Brake feel was much more solid with the uprated brake fluid (that doesn't boil on the limit) and I've been much happier with the brakes since. There's still a little bit squirm under maximum braking - but I had a bit of a driving lesson from Roland to sort that one out. ;) It's the first high performance brake kit I've ever purchased, so didn't really know what to expect or how to properly drive a rapidly decelerating car.

I've found that having put a few hundred additional miles on them, they've also quietened down a bit - although they're not entirely silent at <10mph speeds when cold. When hot: I can't hear them at all when the windows are up, and you have to listen quite carefully with the windows down to pick it up <10mph.

I've just taken these minor chirps as a characteristic of Kevlar pads and the phenomenal stopping power of the Spiroslots more than makes up for it. :D If I had to do it all again, I'd still get the Spiroslots, but I'd have them installed by GTT in the first instance.

All the best,

I hope you found that helpful. :)

All the best,

1,918 Posts
Best way to stop any squeeling is to USE them :D

Find some nice quiet roads and do ten 60mph to 10mph hard stops then drive for 10-15 mins without using them if possible to let them cool.
You might have to do this a couple of times but it WILL make them nice and quiet :)
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