What size tyre should I fit?

[kaanage]

My 18x8 +35 offset wheels JUST clear at the rear, and I have 5mm clearance to the struts at the front.

So logically, the maximum offset for a 7.5" width rim would be +41mm and for 7.0" would be +47mm.
I might not need spacers (they'd only be for track use anyway)

[Blitzen]

Yeah. They may just fit. I hope they do for him though.
The way I look at it in my twisted logic is the difference between the 7.5in and 8in wheel is about 12.6mm, and the difference between my +35 and his +45 offsets are 10mm, so 12.6 - 10 = 2.6mm.... Therefore his inner wheels will be 2.6mm closer to the struts/rear damper/fuel filler neck than a 18x8in +35 offset wheel.

[vwthunder]

Just my opinion, but I would never run spacers. They are illegal in Australia (unless fitted as OEM like on some Porsches), and if they are found on a car, you can be defected, and could lead to your insurance being voided if in an accident. It's your car though, and I'm just giving you a heads up.

I dont know what the laws are in Canberra but in Vic your 18X8's are illegal, you can only go 1 inch wider, so standard is 6.5 you can only go to a 7.5inch wheel

Oh and your rolling diameter is illegal too

[dylan8]

leegil when you test fit the wheel make sure you put all the cars wieght onto the wheel... dont just bolt it up and leave the car in the air on the hoist/jack.
215/35 sounds best. should sit pretty straight and be close to your roller dia compared to 215/40.
Blitzen he should actually be more like 4mm closer on 7.5et45 vs your 8et35, but then again cars height, wheel brand, tyre brand can all make a difference. even the car itself can make a difference to the next polo gti sitting besides it.

[kaanage]

he should actually be more like 4mm closer on 7.5et45 vs your 8et35,

Why would you say that?
I'm with Blizten's figures (except 1" = 25.4mm so 0.5" = 12.7mm => 0.1mm difference ~ 0 for our purposes)

[vwthunder]

My Bora sports I think ET35 ? 7.5 wide and i had a 3 mm spacer, was so close to the strut, the tyre wore through the cable for the traction control and ABS

[noone]

1 inch wider rim affects the backspacing by 1/2 inch.

8 inch rim would have the same clearance as 7 inch version with 12.5mm greater offset.

[Blitzen]

I dont know what the laws are in Canberra but in Vic your 18X8's are illegal, you can only go 1 inch wider, so standard is 6.5 you can only go to a 7.5inch wheel

Oh and your rolling diameter is illegal too

The laws I have read for Qld are that a wheel can be any size, but must be within +15 to -26 of the OEM outer diameter of the tyre, so yes, my wheels do exceed this.
Wheels can be 1.3 times wider than the largest option can be fitted (in the case of the Polo, this is the 'Exor', which was 17x7.5), which means the Polo can be fitted with wheels 9.75in wide!! Haha.

[kaanage]

My Bora sports I think ET35 ? 7.5 wide and i had a 3 mm spacer, was so close to the strut, the tyre wore through the cable for the traction control and ABS

So how thick a spacer did you end up running with the Boras, vwthunder?

[vwthunder]

So how thick a spacer did you end up running with the Boras, vwthunder?

3mm

just had to move the cables down a little and cable tie them to the strut, so it dosent come into contact with the moving tyre

[kaanage]

Ah, OK. I thought you may have gone to a thicker spacer. And was this with 215 or 205 width tyres?

[vwthunder]

Ah, OK. I thought you may have gone to a thicker spacer. And was this with 215 or 205 width tyres?

205/40/17 .

[leegil]

OK, I mounted the 18"x7.5", ET45 Speedy FIN wheels onto the car.

I bolted the ball seat bolts of the VW just enough tightness to hold it in proper place (Speedy FIN uses taper seat bolts). Going to have to buy the correct bolts.

There was a lot of spacing between the rim edge and the suspension (the closest bit). Everything else also had excellent clearance (the hose in the front, the calliper etc.). Nothing looked like it would even come close to touching. There was also more gap once I placed my finger between the suspension strut and the rim. Estimate say 15mm in total gap.

Will get the tyres fitted tomorrow. 35 profile should clear very easily.


the caps have subsequently also been painted black.








(oops, that's the painted badge and 'I')

[noone]

everything moves when the car is sitting on the rims. they may touch when you do go over a speed bump, etc. Time will tell...

Any tyre shop should be able to help you out with bolts, avoid anything chromed.

So, how long until you drop it?

[Catfish]

OK, I mounted the 18"x7.5", ET45 Speedy FIN wheels onto the car.

I bolted the ball seat bolts of the VW just enough tightness to hold it in proper place (Speedy FIN uses taper seat bolts). Going to have to buy the correct bolts.

I've got a set of brand new good quality taper-seat spline-drive bolts (with key) you can have cheap ($30).

I'm also in Canberra, so give me a call on 0402 400 578 if you're interested.