DIFFERENT TYRE SIZES FRONT TO REAR?

[muppetlab 0]

After some nightmarish months trying to get the tyres to fit under the arches on my vr it seems that the slight pull to the left which i kept meaning to do has completely scrubbed off the nearside tyre and left the drivers side half worn :bad-words:

I knew i should have looked at it sooner. Think its just the tracking thats out as one side does look like it is angled different to other. Also do people run more camber on the nearside to account for the camber of the road? To get over the arch tyre relationship i am looking to go narrower on the front. Currently on 215 40 17 all round but looking to drop to maybe a 195 40 17 on the front. Can anyone tell me if this will cause a problem with the abs system running wheels that are different diameters or are the sensors reading cross each axle independantly and also will a 195 40 17 be better or worse than a 195 45 17?

thanks jez

[Kevin Bacon 5]

Also do people run more camber on the nearside to account for the camber of the road? To get over the arch tyre relationship i am looking to go narrower on the front. Currently on 215 40 17 all round but looking to drop to maybe a 195 40 17 on the front. Can anyone tell me if this will cause a problem with the abs system running wheels that are different diameters or are the sensors reading cross each axle independantly and also will a 195 40 17 be better or worse than a 195 45 17?

thanks jez

 

Good question, I've thought about that aswell, but camber itself doesn't generally cause a car to pull (unless it's miles out and pulls the toe out with it). It's toe and caster that affect the car's straight line tracking. When the car is perfectly set up, you only need the slightest correction on adverse cambers. If you're permanently fighting to keep it in a straight line, then it desperately needs realignment!

 

I don't think the VR6's ABS is sophisticated enough to compare rolling radiuses (or raduii?) across axles. MK5s do that and put the TC light on if you fit a space saver. I've tried all manner of wheel sizes on mine and never got an ABS light.

[muppetlab 0]

Excellent shall go with the skinny fronts then. Must align the front properly first though. Will have a go and see if i can improve it this week and then get it in a garage for fine tuning. All the height and camber adjustments have messed it right up. Things we do to get shiny wheels to fit when its clear that they really would rather not. Think the rack needsto be centred too.

[muppetlab 0]

Just a follow up. Had the smaller 205's fitted on the front and had an alignment done and no rubbing on arches and i have a bit of "poke" so i am told! one thing i have noticed is the car was spot on, tracked perfect when i collected it but now it has a slight pull to the left. I thought it was tracking until i tried coasting out of gear and it runs perfectly straight. I suspect the diff or gearbox might be causing an imbalance? anyone have any ideas? cheers

[g0ldf1ng3r 14]

im currently running 195/50/15 on the front & 205/50/15 on the rear & all is fine, she was mot'd like it too

 

in fact, & pls correct me if im wrong but i believe that up until the final face lift model the rado's were fitted with 195/50/15s all round :)

 

on the ABS front, from what i can gather the sensors pick up the signal or whatever from a circular disc with lots of holes in the region behind the brake disc....thus not wheel dependant if you get me

 

hope that hleps lol

[Roger Blassberg 0]

In answer to your query about whether the ABS system will be upset by different sized rolling radii, I would have thought that the system must have an inbuilt tolerance to different wheel speeds to account for the differential action when going around corners.

 

Best wishes

 

RB

[muppetlab 0]

Well got them on now and have no problems. Has cured my arch rubbing so cant be bad. Toyos not as grippy as the yokos but hopefully will wear better. cheers