Wheel Arch Rolling

[domhart10]

Hi guys, not really seen this on here but something I have started thinking about and wanted to start researching is arch rolling?

With more power coming to the front I think it you be good to widen the stance to improve any grip I can to aid cornering really. My fronts sit very very snug to the wheel arches with some bilstein coilovers but I was thinking of getting some spacers to push the wheels out wider a bit more.

If the weels are pushed out more im guessing I will need to lift / roll or just do something to the arches to allow the wheel to come out a bit? I dont really want to cut and stick in any arch flares just yet.

Does anyone know anything about these setups or rolling arches really? best way without doing too much damage?

And also any downsides with using wheel spacers?

[lockstock]

Originally Posted by domhart10

Hi guys, not really seen this on here but something I have started thinking about and wanted to start researching is arch rolling?

With more power coming to the front I think it you be good to widen the stance to improve any grip I can to aid cornering really. My fronts sit very very snug to the wheel arches with some bilstein coilovers but I was thinking of getting some spacers to push the wheels out wider a bit more.

If the weels are pushed out more im guessing I will need to lift / roll or just do something to the arches to allow the wheel to come out a bit? I dont really want to cut and stick in any arch flares just yet.

Does anyone know anything about these setups or rolling arches really? best way without doing too much damage?

And also any downsides with using wheel spacers?

read up on cornering dynamics and tyre width in wet and dry. The problems arise not generally because of the contact patch but because of the inherent issue of having the tyres steer and drive power. Widening the tyres will actually, most likely worsen the steering and handling characteristics. You may get improvements in dry weather straight line traction. I wet weather and cornering you won't gain. Widening the track wont make much difference. The suspension is a McPherson strut, not a double wishbone so you will be limited by what improvements you can make to handling characteristics. Stiffening the suspension will reduce body roll, but will actually reduce front end traction. It's not straight forward to get real gains. I'd find someone who has stripped out a t5 for track use and read up on what worked well, what badly. And remember the car will be terrible to drive on British potholed roads.

edit:
just read some of your build thread so you are probably already familiar with the above

[domhart10]

Originally Posted by lockstock

read up on cornering dynamics and tyre width in wet and dry. The problems arise not generally because of the contact patch but because of the inherent issue of having the tyres steer and drive power. Widening the tyres will actually, most likely worsen the steering and handling characteristics. You may get improvements in dry weather straight line traction. I wet weather and cornering you won't gain. Widening the track wont make much difference. The suspension is a McPherson strut, not a double wishbone so you will be limited by what improvements you can make to handling characteristics. Stiffening the suspension will reduce body roll, but will actually reduce front end traction. It's not straight forward to get real gains. I'd find someone who has stripped out a t5 for track use and read up on what worked well, what badly. And remember the car will be terrible to drive on British potholed roads.

edit:
just read some of your build thread so you are probably already familiar with the above

yeh man am find sacrificing ride quality as my car is the lowest it can go before slamming now. I have 235/45 tires on which has improved cornering massivly but after this K16 comes on I would like to improve cornering as much as I can.

I have read about quite a few ST's running big power and they have sacrificed cornering for straight line power which im a bit worried about really.

It is defenitly on the list to stip the car which will also help.

I am constantly chatting with a guy who has widened his S40 T5 for track but using flared wheel arches and although theylook good, it was a massive job which im shying away from.

I dont know if anyone has put on spacers and had any problems with driveshafts etc? as im guessing the further pressure would cause even more strain?

[lockstock]

Originally Posted by domhart10

yeh man am find sacrificing ride quality as my car is the lowest it can go before slamming now. I have 235/45 tires on which has improved cornering massivly but after this K16 comes on I would like to improve cornering as much as I can.

I have read about quite a few ST's running big power and they have sacrificed cornering for straight line power which im a bit worried about really.

It is defenitly on the list to stip the car which will also help.

I am constantly chatting with a guy who has widened his S40 T5 for track but using flared wheel arches and although theylook good, it was a massive job which im shying away from.

I dont know if anyone has put on spacers and had any problems with driveshafts etc? as im guessing the further pressure would cause even more strain?

the moment of enertia from wider wheels/bigger offset/spacers, will act upon the bearing and possibly the hub. Unless the bearing is actually distorting (i which case you are stuffed anyway) I don't see how it would affect the driveshafts. Massively lowering the car will change the geometry in an unfavourable way and this 'may' affect the driveshafts but you would have to look into this. Again slamming this car, given the McPherson strut design wont improve traction and handling. Does the focus ST use the same differential set up as the T5? as this will affect cornering and putting power down. extra power simply will never mean faster cornering ability. Weight distribution, complient suspension and good tyres will. On track, accelerating out of the apex and getting power down out of the corner will be benefited by extra traction. But, a better balanced car with less power will be faster on some tracks than a slammed, widened, higher power car with overly stiff, low suspension. The only way to know for sure is trial and error, learning from others and racing the same circuit with and without changes.

[domhart10]

haha ,yeh in no way am I every going to think of slamming this car.

There is nowt I can do about the power now so just listing out all the next steps for improvement with cornering really. I do have an LSD on the list for the car but wanted to know how beneficial widening the front stance would be and if worth it for cornering.

Has no one put spacers on their car? felt any actual difference in handling at all? or real minimal improvement if any?

[lockstock]

Originally Posted by domhart10

haha ,yeh in no way am I every going to think of slamming this car.

There is nowt I can do about the power now so just listing out all the next steps for improvement with cornering really. I do have an LSD on the list for the car but wanted to know how beneficial widening the front stance would be and if worth it for cornering.

Has no one put spacers on their car? felt any actual difference in handling at all? or real minimal improvement if any?

spacers increase the ET offset, which means the pivot point of the hub is further from the centerline of the wheel. I 'think' this could affect Ackerman angle. In this case it would negatively affect cornering. Small differences of 10mm probs make no noticable difference. Widening track by using longer control arms and driveshafts wouldn't cause this problem so may give some benefit. Also if wider wheels/tyres with standard offset fit without scrubbing they increase track width.

Also extra power doesn't make cornering 'worse' you just need talent to modulate throttle and not use all the power too soon! :-)

[domhart10]

Originally Posted by lockstock

spacers increase the ET offset, which means the pivot point of the hub is further from the centerline of the wheel. I 'think' this could affect Ackerman angle. In this case it would negatively affect cornering. Small differences of 10mm probs make no noticable difference. Widening track by using longer control arms and driveshafts wouldn't cause this problem so may give some benefit. Also if wider wheels/tyres with standard offset fit without scrubbing they increase track width.

Also extra power doesn't make cornering 'worse' you just need talent to modulate throttle and not use all the power too soon! :-)

haha thanks man, yeh even though I try go flat out on the track I defenitly do not have the tallent. I do already have the wider tires 235 on my wheels and I think thats the safest I would go really.

Sorry what do you mean by widening control arms and driveshafts? can you get wider versions on these?

[lockstock]

Originally Posted by domhart10

haha thanks man, yeh even though I try go flat out on the track I defenitly do not have the tallent. I do already have the wider tires 235 on my wheels and I think thats the safest I would go really.

Sorry what do you mean by widening control arms and driveshafts? can you get wider versions on these?

I meant hypothetically. I don't know if there are wider options available aftermarket. Probably not. I was saying this would be the better way to widen the track than spacers.

[D6Stevie]

Arch rolling is pretty easy. you can either make your own roller or get one fom fleabay
I’d guess around the£50 mark. Before you start to roll them get the inners as dirt free as possible (once inner splashguards are removed) Also check for any seam
sealer you can find it wants to be as much removed as possible then you’ll need a decent watt heatgun and heat the arch before and all the way during rolling. This prevents, or rather helps prevent the paint cracking.
Do it full sweeps at a time again heating all the time and have the area workkng
on hot before attempt to roll.