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VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Mon Jul 16, 2018 8:57 pm
by Bodyboarder
MrPT ..... sorry one more question. What size Tyres are you running ?
Thanks
VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Mon Jul 16, 2018 9:21 pm
by MrPT
Bodyboarder wrote: ↑Mon Jul 16, 2018 8:57 pm
MrPT ..... sorry one more question. What size Tyres are you running ?
Thanks
235/40/19 and 265/35/19.
VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Mon Jul 16, 2018 9:26 pm
by Bodyboarder
They look spot on in your pics .... most I’ve read go for 235/35 265/30 ... why the bigger 40/35 profile ? And no rubbing still ?
VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Mon Jul 16, 2018 9:30 pm
by MrPT
Bodyboarder wrote: ↑Mon Jul 16, 2018 9:26 pm
They look spot on in your pics .... most I’ve read go for 235/35 265/30 ... why the bigger 40/35 profile ? And no rubbing still ?
Ah, pics were with 235/35 and 275/30. Went up in profile to improve the ride. Rear is fine - front needs some mild arch modding.
VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Tue Jul 17, 2018 8:31 am
by Bodyboarder
What’s involved to mod the front ?
Appreciate the info
VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Tue Jul 17, 2018 8:55 am
by MrPT
Bodyboarder wrote: ↑Tue Jul 17, 2018 8:31 am
What’s involved to mod the front ?
Appreciate the info
Just drive around very fast until the horrendous scraping noise stops.
Seriously, it’s not worth it - you need to heat and push out the arch liner around the front brake vent and shorten the vent itself, roll out the upper, outer arch lip and a small patch directly to the rear of the tyre. 245/35 is a better choice if you want a higher profile front tyre with slightly larger contact patch. Most of the improvement in ride quality comes from changing the rears.
VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Wed Jul 18, 2018 12:56 pm
by Bodyboarder
Last question.... ( probably not
)
To run 5mm spacers are longer bolts required ?
Thanks
VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Wed Jul 18, 2018 1:32 pm
by BMWZ4MC
I run a set of appropriately longer bolts with each set of spacers (I have lots of spacers - 5mm, 12mm, 15mm and 20mm - and so I have 80 bolts not in use at any one time
).
If there are at least seven complete turns of the OEM bolts engaged when running the 5mm spacers, strictly speaking you don’t need longer bolts.
VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Wed Jul 18, 2018 3:05 pm
by TomK
Personally I would never run a 5mm (or anything less than a hubcentric 10 for that matter), it's an unnecessary safety risk imo.
With a 5mm you are almost halving the size of the ledge on the hub that the wheel sits on and placing more load on the wheel bolts. Since many wheels have the center bore chamfered the 7mm you have left can be an issue.
There's also the potential problem if they have not been machined properly of causing vibrarions.
Either get a hubcentric spacer (minimum possible is 10mm) or don't use a spacer at all imo.
VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Wed Jul 18, 2018 4:10 pm
by craig3.2
TomK wrote: ↑Wed Jul 18, 2018 3:05 pm
Personally I would never run a 5mm (or anything less than a hubcentric 10 for that matter), it's an unnecessary safety risk imo.
With a 5mm you are almost halving the size of the ledge on the hub that the wheel sits on and placing more load on the wheel bolts. Since many wheels have the center bore chamfered the 7mm you have left can be an issue.
There's also the potential problem if they have not been machined properly of causing vibrarions.
Either get a hubcentric spacer (minimum possible is 10mm) or don't use a spacer at all imo.
I would second that,spacers should be hubcentric,and as said,need to be 10 or 12mm.(depends on make,some 10mm makes are hubcentric,some aren't stated as being by the said manufacturers until 12mm), tWhich is what I found out.
10/12mm on the front with the 245/35 profile shouldn't rub,from what others have had fitted over the years
VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Wed Jul 18, 2018 4:13 pm
by craig3.2
Bodyboarder wrote
What's involved to mod the front?
MrPT wrote
Just drive around very fast until the horrendous scraping noise stops.
[/quote/
That made me laugh
VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Wed Jul 18, 2018 5:02 pm
by Bodyboarder
My front wheels specs are 19” 8.5 et40 , running a 245/35 tyre .... with a 10mm spacers I’d be at et30 . I’m on eibach springs ... do you think I’ll rub? I do plan to go to a 235/35 265/30 tyre combo also
VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Wed Jul 18, 2018 5:15 pm
by bmwaddict
Bodyboarder wrote: ↑Wed Jul 18, 2018 5:02 pm
My front wheels specs are 19” 8.5 et40 , running a 245/35 tyre .... with a 10mm spacers I’d be at et30 . I’m on eibach springs ... do you think I’ll rub? I do plan to go to a 235/35 265/30 tyre combo also
I'm running 19x9 et38 with a 245/35 tyre fitted, lowered 25mm it does rub a bit on full lock. I plan to fit this brake kit too, so I will have similar issues to contend with.
For your 19x8.5 the ideal tyre size would be 235 width, and you shouldn't have any rubbing issues, bear in mind that different makes of tyre have slightly different shape sidewalls eg. MPSS are very straight and slender, where as GY F1s have a chunky rim protector, and a much more bulbous sidewall shape.
VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Wed Jul 18, 2018 5:27 pm
by Bodyboarder
I guess the sensible thing to do would be buy the Tyres , then the 10mm spacers and see how she goes before purchasing the lovely Brembo’s !
VagBremTechnic Big Brake Kit for E85/E86 Z4 'M' models
Posted: Wed Jul 18, 2018 9:09 pm
by RedUn
TomK wrote: ↑Wed Jul 18, 2018 3:05 pm
Personally I would never run a 5mm (or anything less than a hubcentric 10 for that matter), it's an unnecessary safety risk imo.
With a 5mm you are almost halving the size of the ledge on the hub that the wheel sits on and placing more load on the wheel bolts. Since many wheels have the center bore chamfered the 7mm you have left can be an issue.
There's also the potential problem if they have not been machined properly of causing vibrarions.
Either get a hubcentric spacer (minimum possible is 10mm) or don't use a spacer at all imo.
I used to think that but some OEMs (Porsche) run a 5mm spacer from the factory... So I tried it (not on the zed) and many track days and ring trips later, it was fine
I did go for longer studs (bolts on the zed) though just to make sure.
I'd happily run them again if need be