Geometry

Hi all

Had a minor crash a few weeks back and have just had the car back from the garage. It was the other guys fault so all paid for by him. (two re-furbed alloys, re-sprayed front bumper and geo check)

Anyway as part of the work done the garage checked my geometry. They said it was out and adjusted it to the Toyota specs.

Before I had the geo done I always noticed a bit of tramlining on bad roads. However since I've had it adjusted I seem to be getting much more tramlining than before and the back seems to step out when driving over drain covers etc. ( i have 8jj 16s all round at present)

Any ideas on why this might be? Excuse my technical ignorance:)

Cheers in advance

Jon

8J's are way to narrow for the rears, are you TT? and what size tyres are you running on the rears?

Nah N/A. Tyre sizes all round are 225/50

mate, get some wider rears for a start

Even for N/A thats just wrong, you should be atleast 245 min on the rears, its a rear wheel drive car, the supra has larger widths at the rears than the front.

Get bigger tyres on them rears, being 8j's you cant really go above 235's wiht out it bulging too much, you need to have atleast 8.5" or preferably 9" rears and slap on some 245's or 255's.

Just read that stock N/A has 225's all round..dint know that, that sounds too narrow.

From reading provious posts I realised they were too narrow but didn't think it would effect the handling so much and it's only since the geo adjust that it's got worse!!? I am looking for some new wider ones as we speak.

Mate if your going to stick with the same wheels then the max you can slap on 8" wheels is 235's anything over wouldnt be advised, id get hold of some decent 17's mate with atleast 8.5" min rears or may be 9" and slap on some 245's or 255's on the rears and 225's or 235's on the front, car should handle alot batter mate.

although i agree that the rear of the car should have wider tyres on, surely making them wider will actually contribute to the tramlining effect he is experiencing?

although i agree that the rear of the car should have wider tyres on, surely making them wider will actually contribute to the tramlining effect he is experiencing?

Good point, the wider wheels will not cure the tramlining but it with help will the handling of the car, dont get me wrong wider and more grip than stock does not mean the car will handle like a dream, but the set up that jon has the wheels seem a bit too narrow for a supra.

Cheers for the info guys. I will certainly be investing in wider wheels ASAP.

Still unsure why the tramlining seems worse after the Geo has been done though. I's be surprised if the garage got it wrong.

Could it be anything to do with the way the tyres have worn previous to the goe being set correctly?

I's be surprised if the garage got it wrong.

really?

Jon are you sure the stock wheels are 225's on stock N/A's, im assuming the garage used the geometry data from the UK supe which has 255's at the rears on 9", if this is the case then that could explain your situation??

really?

Well ok maybe they did get it wrong they just seemed to know what they were doing. May be worth a return visit I suppose

Jon let them know that the setup of the wheels etc are different from the UK as they have much wider wheels front and rears, so the geometry data maybe incorrect for the N/A, i dont know if this could be a cause as i dont know much about geometry setup's.

Jon are you sure the stock wheels are 225's on stock N/A's, im assuming the garage used the geometry data from the UK supe which has 255's at the rears on 9", if this is the case then that could explain your situation??

Hmmm good point. They were well aware that it was an import but will double check with them anyway. Although maybe it's worth me getting the wider wheels first.

Get the wider wheels, as its recomended anyway try and get close to stock as close as possible, i.e offset +50, trye width etc, and then get them balanced, tracked etc and make sure they are aware of the difference between uk spec and N/A as N/A have narrower wheels and tryes.

Again Jon i dont know if it makes a differnce, TBH you should get in contact with Chris Wilson, he has this subject well and truly sussed.

HTH

It will be fine on 8 inch rims all round, and assuming they are the correct offset the handling should be fine, too. I suspect they have cocked up the alignment, I regularly see abject horrors straight from a "Super Laserline Geo Computertech" setting up, so it wouldn't be at all surprising.

Chris surely the rears should have meatier tyres ??

I don't know what size rims an N/A comes from the factory on, but I actually prefer them on 8 inch all round, even TT's are pretty nice to drive on 8 inch all round, I consider a lot of cars are over wheeled and tyred, even from new, stock, for purely cosmetic and fashion reasons. It should certainly handle fine and not tramline on the rims he has, IF they are the right offset.

Thanks Chris,

The wheels are standard toyota so I assume the offset is correct. Looks like it's back to the gargage then!!!

Cheers all

Jon

You HAVE carefully checked the rear tyre pressures are about 34 PSI and the same both sides??? !!!

Checked the pressures and they are fine.

One thing I noticed is that the wheel that was on the front is now on the back and vice versa. Could this be the problem because the two front tyres only have around 3mm of tread but the rears have around 5mm. So now that they have been swapped I have one tyre on the front with 3mm and one with 5mm and the same on the back. This can't be good for handling!!!