GR86 GR86 - Brake Upgrade Guide

For those with a BBK on their GR86, did you add it as a mod to insurance and did it make a difference to the premium? I’m not sure that ‘better brakes’ is really something that needs to be declared is it?
My insurance company won't insure me with any modification to the brakes!
 
Swiftcover
Yeah, found them to be the same with anything outside of their ‘standard’ mods list. Did you call and ask them at all?
Have managed to find fully comp for 390 including modded exhaust, tyres and uprated brakes from Esure Flex. Will let Howdens have a try nearer the time to see if I renew or not.
 
Yeah, found them to be the same with anything outside of their ‘standard’ mods list. Did you call and ask them at all?
Have managed to find fully comp for 390 including modded exhaust, tyres and uprated brakes from Esure Flex. Will let Howdens have a try nearer the time to see if I renew or not.
Yeah, they said no. I couldn't complain as they were significantly cheaper than anyone else at the time. The nearest competitor who would insure those mods were £250 more expensive. It wasn't worth it, so I will revisit it in April when my renewal is up.
 
For those with a BBK on their GR86, did you add it as a mod to insurance and did it make a difference to the premium? I’m not sure that ‘better brakes’ is really something that needs to be declared is it?
I added it to mine but I'm not sure the exact figures because I changed something else at the same time. The total was less than 15% from memory.
 
BBK @Godspeed kit fitted to GR86 today. Immediate and subsequent issue with tyres rubbing at full lock and it has damaged a small area the wheel arch underseal work that I had done by ‘Preserve and Protect’ in February 🫨.
I’m wondering if it might be an issue caused by having 225/40R18 tyres on the OEM rims instead of the standard 215/40R18 tyres?
I have never had any rubbing from the bigger All Season tyres on the OEM rims before today, so the only change has been the BBK. It now means the car is parked up for a few days on the drive to avoid any more damage.
So on Monday, despite having only been used for 3 months last Winter, I’m gonna swap out these Vector 4season 225s for a new set of Goodyear Vector 4Seasons in the regular (but more expensive) 215 size and see what happens.
Hypertech is standing by for a bit of fault finding next week if new tyres don’t solve the issue. My last ditch solution might be a thin set of spacers which I’d like to avoid if possible 😕.
I believe that there may be other members out there with this BBK that are also running 225 tyres? Have any of you had issues with rubbing? Thanks for any input.
IMG_7219.jpeg
 
Is the brake disc hub of the bbk thinner than that of the the stock disc? That's the only way I can see it affecting the wheel offset. Perhaps you might need a spacer to correct it.
 
Where exactly is it rubbing?

I'm using 225 40 18's. And have them on both oem wheels and 18x8 et45's.
Thing is... They rubbed (on the aftermarket wheels when installed) at full lock , I recall mainly on a right turn. But...what's worse is that it stopped randomly. And I've jacked the car up since, no idea.
I had a feeling it's cos I'm running -2.3 camber and it's very close to the strut, that paired with the disc being perhaps a smaller offset pulled the wheel in even further - but doesn't add up now it's stopped.

Also noticed your caliper looks different. Was that the £999 one (clio fitment, I think?) or the £1200 megane one. Mines the latter.
 
Is the brake disc hub of the bbk thinner than that of the the stock disc? That's the only way I can see it affecting the wheel offset. Perhaps you might need a spacer to correct it.
I’m looking at the amount of ‘spindle’ (?) showing in my photo above and don’t remember that much showing with the OEM hub when I’ve swapped wheels over? I may be mistaken of course. Hopefully we’ll come up with a solution next week; phase 1 being a new set of tyres (stop crying wallet, it’s only money 😭).
 
Why don't you want to use spacers? Surely that would be better than changing the tyres? You only want to restore the offset you had before the BBK install, so its not like you have to worry about suspension geometry, bearing wear, etc.
 
Where exactly is it rubbing?
Inner lower rear face of both wheel arches, so when on full left lock (left wheel arch) and full right lock (right wheel arch).
Also noticed your caliper looks different. Was that the £999 one (clio fitment, I think?) or the £1200 megane one. Mines the latter.
Smaller/cheaper set which is STi I think?
 
Oh dear that's not very good. The 215s are slightly stretched on the stock wheels, 225 will give flat sidewalls, not a drastic change and shouldn't cause rubbing. I'm with the other guys, the thickness of the disc bell has changed, it's increased your wheel offset causing it to rub. Thats pretty poor IMO.

Edit: Not the issue.

You can run slip on spacers to correct it but you shouldn't have to in the first place and you will lose the centre bore fitting, it would just be sitting on the studs.
 
Last edited:
Why don't you want to use spacers? Surely that would be better than changing the tyres? You only want to restore the offset you had before the BBK install, so its not like you have to worry about suspension geometry, bearing wear, etc.
I’m not wholly anti-spacers, I’d just like to avoid them as they’re another insurance modification to declare. Going back to 215 tyres removes one element in the fault finding chain, as well as letting me remove ‘wider tyres’ from my insurance. Once we get to the bottom of the problem I’ll be able to let @Godspeed know about the issue and assist future customers.
 
That's fair enough, I forgot you might have to declare them.

Another option might just be to have at the wheel arch liner with a Dremel :D
 
Thing is... They rubbed (on the aftermarket wheels when installed) at full lock , I recall mainly on a right turn. But...what's worse is that it stopped randomly. And I've jacked the car up since, no idea.
Could is just be that if it was rubbing against the plastic wheel arch liner, it just wore away enough material to eventually stop making contact?
 
Could is just be that if it was rubbing against the plastic wheel arch liner, it just wore away enough material to eventually stop making contact?
I agree. Mine is a very small contact area (will try and get a photo in daylight tomorrow) and the lightweight/ally construction makes the noise super apparent 🤯
 
…225 will give flat sidewalls, not a drastic change and shouldn't cause rubbing. I'm with the other guys, the thickness of the disc bell has changed, it's increased your wheel offset causing it to rub. Thats pretty poor IMO.

You can run slip on spacers to correct it but you shouldn't have to in the first place and you will lose the centre bore fitting, it would just be sitting on the studs.
Agree. I researched 225s before I had them fitted and the profile was judged as square.
There certainly appears to be a ‘compatibility’ problem with the kit I have and my GR86 judging by the results seen today. That said, I’d prefer to gather what data I can with Hypertech’s assistance, pass it on and perhaps prevent others from having this issue in the future. Fingers crossed for a robust solution.
 
Agree. I researched 225s before I had them fitted and the profile was judged as square.
There certainly appears to be a ‘compatibility’ problem with the kit I have and my GR86 judging by the results seen today. That said, I’d prefer to gather what data I can with Hypertech’s assistance, pass it on and perhaps prevent others from having this issue in the future. Fingers crossed for a robust solution.
Absolutely ,I hope you get it sorted quickly. I think if it was me I would measure the length of exposed stud on the godspeed disc and then on a standard disc to get an idea of what's going on, assuming it is that of course.
 
Last edited:
I did actually buy some 3mm shim spacers when mine started rubbing, only paid ike £20 from ebay. I never fitted them though as it stopped (I'll check to see what's worn, couldn't see anything though) ... It's worth a go for that sort of money as buying 225 tyres will save you money in the long run compared to 215. More choice too.
 
Back
Top