Borbet A troubles.. help!

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scottiemorris
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Mon Jun 23, 2008 9:27 pm

i recently got myself a set of perfect borbet a's 9 inch all round for my 325, my suspension is totaly standard, my problem is when ive just 1 person in the back and a go over a bump or dip about 50mph the arch screeches of the tyre at the back.. i'm concernd that it may bottom out and the arch will damage the rim of my alloy... would really stiff suspension and a small drop help? as i want 2 lower it a bit..?? any suggestions appreciated!
march109
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Mon Jun 23, 2008 9:30 pm

scottiemorris wrote:i recently got myself a set of perfect borbet a's 9 inch all round for my 325, my suspension is totaly standard, my problem is when ive just 1 person in the back and a go over a bump or dip about 50mph the arch screeches of the tyre at the back.. i'm concernd that it may bottom out and the arch will damage the rim of my alloy... would really stiff suspension and a small drop help? as i want 2 lower it a bit..?? any suggestions appreciated!
Have your arches rolled or flared, 9J is a bit wide! A drop will make the problem worse as it won'tmove the topof the tyre in much but will bring it closer to the arch lip.

And I'd be more worried about the arch shredding the tyre at 50mph!
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leeparkes
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Mon Jun 23, 2008 9:35 pm

What offset are they?
usually stamped ET then the number!
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felt so proud,even tried it with a E30 325i and got put in my place.. :o:
scottiemorris
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Mon Jun 23, 2008 9:36 pm

yea i was thinking maybe harder sporty suspension witha a drop would compensate a little bit? how much does rolling/flaring cost roughly? and do e30's have bump stops or anything like that, could bigger ones stop the arms going all the way up so the tyre doesnt contact the arch..
scottiemorris
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Mon Jun 23, 2008 9:38 pm

hey lee, am not sure.. they fit on fine though. is it on the rim itself, where borbet is stamped?
leeparkes
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Mon Jun 23, 2008 9:47 pm

not sure where they are stamped on borbets but the lower the (ET) number the more the wheels will stick out,but as they are 9"wide you havent got a lot to play with plus you say its catching on the arches (inner or outer) if its catching on the inner arch you can solve it with spacers
if its catching on the outside you have no choice but to have the arches rolled
you could try the stretched tyre look but not sure how low you can go on 9"rims
what width tyres are on at the mo?
Cypriotgeeza wrote:I done both my mates in my old 318is
felt so proud,even tried it with a E30 325i and got put in my place.. :o:
scottiemorris
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Mon Jun 23, 2008 9:55 pm

its the outside, ive got stretched on the now, i'd say its as far as you could go really its pretty stretched, looks like iam gonna have to get themem rolled!
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touringsport
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Mon Jun 23, 2008 10:04 pm

Hi mate. I've got borbet A's on my car, 9j on the back- i had -60mm springs which scrubbed a tad with two people, now i have -40mm which is fine. I'm using 215/40/16's.
The lower the car, the more the camber moves the wheel away from the arch- within reason though :cool:
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leeparkes
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Mon Jun 23, 2008 10:10 pm

Easiest way ive found to see where wheels catch on the arch is to drive the rear wheel on to a quite high gutter and leave the front wheel on the road (if that makes sense) then get some people to sit in the back (or slabs in the boot) then you will have a better idea of where its catching,they may just need tapping back in certain places
but make sure you dont leave bare metal if you tap them back or you wont have any arches left through the rust worm
good luck!
Cypriotgeeza wrote:I done both my mates in my old 318is
felt so proud,even tried it with a E30 325i and got put in my place.. :o:
Jonsku
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Tue Jun 24, 2008 7:57 am

You've to get your arches rolled. 215/40 with -60 or -40 springs works fine, but the arches need to be rolled.

Usually 9x16" borbet A ET is 15, which is just fine. Do they roll nicely in the front (ET also 15 and 9" wide?)
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