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Hey fellas,

Just bought some new shoes and waiting for them to arrive.

They are 17x7.5 ET38, and thinking about running 225/45R17 (probably Dunlop Z1 Star Spec or Continental Extreme Contact DW)

Do you guys think the rear guards will need to be rolled? This is for a 2007 NC PRHT

And where are the cheapest places to get some tyres? I can get Dunlop off of tire rack but not continental

Ta

online wheel/tyre calculator, a tape measure and your own car will get you an answer in 3 minutes.

I'm running 17x8 but ET50 with 235/40/17.
Plenty of clearance but I'd reckon your et38 might need a little roll if the car is lowered much
works out ~7mm that the outer rim is further outboard...tyre is a little narrower depending on the actual section.

All depends on how low you are Kev. If your tucking tire then you will need a roll or a 215 tire.

see here -


Old New
Diameter 616.3mm 634.3mm
Circumference 1936.2mm 1992.7mm
Poke 33.9mm 57.3mm
Inset 143.9mm 133.3mm
Speedo error 0% -2.84%
Reading at 30mph 30mph 29.15mph
Reading at 60mph 60mph 58.3mph
Ride height gain 0mm 9mm
Arch gap loss 0mm 9mm

So your new wheels are going to sit out around 24mm compared to the stock ones, if memory serves me right that will be flush, that means a roll is needed, especially with 225's. If you don't want to roll for some reason, then you could squeeze the 205's on there, but i don't recommend that. Ideal size for a 7.5 is 215, i'd go 215 with a bit of neg camber and guard roll.

ksharp wrote:Hey fellas,

Just bought some new shoes and waiting for them to arrive.

They are 17x7.5 ET38, and thinking about running 225/45R17 (probably Dunlop Z1 Star Spec or Continental Extreme Contact DW)

Do you guys think the rear guards will need to be rolled? This is for a 2007 NC PRHT

And where are the cheapest places to get some tyres? I can get Dunlop off of tire rack but not continental

Ta

You need to read this: http://www.tirerack.com/tires/tires.jsp ... uper+Sport

thanks guy, I'll roll the rear guards just to be safe.

Where is a good place to source some Michelins since tire rack can't sell them to Aus?

I have 17x7.5 +50 on 225 45 tyres.

I put on 10mm spacers for 2 days to see if it rubbed. No rub.

lowered about 1 finger between tyres and arch.
-2.3 camber.

I'm guessing it won't rub. If it does.. Then roll it don't roll before you try!