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cvw74

any mathematicians out there

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help needed on total height of tire and wheel.

 

at the mo running winters - 6.5 x 15 with 205/55 rubber.

 

trying to decide on summers at mo

 

if i run a 9x16 with 205/40 or 215/35 also 8.5x17 with 205/40

 

would there be much difference in heights?

 

thanks

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If you run 40 profile on 16" wheels your car will be undergeared. Good for acceleration, but bad for fuel economy plus your speedo will underead your speed by around 4%

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If you run 40 profile on 16" wheels your car will be undergeared. Good for acceleration, but bad for fuel economy plus your speedo will underead your speed by around 4%

 

 

not thought about all that, on a 9x16 whats the best to run, as to be low though. As much as i want 16's may be better option to go 8.5x17

 

sump may be safer as well

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If you go for a 45 section on a 16 inch wheel it shouldnt be any lower than a std wheel.

 

I think 8.5's would be on the wide side as wellespecially in 17 inch

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My workings make it the 15inch wheel with the 205/55 rubber should be 303.25mm to wheel centre.

 

The 16inch wheel with 205/40 rubber should be 285.2mm to wheel centre.

 

The 16inch wheel with 215/35 rubber should be 278.45mm to wheel centre.

 

The 17inch wheel with 205/40 rubber should be 298.1mm to wheel centre.

 

 

Hope my calcs are right and hope this helps.

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I ran 205/40/17 on 8J rims on an old Corrado.

 

With an 8" rim a 205 section tyre will give you a fairly decent stretch already, but the car should drive well. I would personally not go as wide as 8½" as I would worry about overstretching them and compromising safety. An 8½" rim is correct for a 225-235 section tyre but there's no way you'll get those on without modifying the arches. Indeed even when I ran 8" rims with stretched 205s I needed to have the front arch lips trimmed back to prevent arch fouling (although the car was also lowered 80mm) and the rears a lesser amount too.

 

It's possibly also worth mentioning that I think every Corrado I've seen running 9" or wider has only done so with modified arches front & back. Indeed even some 7½" wheel designs (e.g. BBS RKII) grind the arch linings away so be a bit careful.

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Just a quick point, i ran 215 40 16's of 16x7's (bbs rxii's) as that is the tire size that came out of the factory for a golf anniversary (Rolling radius 270mm)

 

and the mk3 vr's run 205 50 15's from the factory which is the same as the corrado vr (rolling radius 270mm), are your current tire sizes not too big - 205 55 15 = 278mm static rolling radius

 

are the 15's your runningn from a mk4 as they tend to have 55 profiles on a 6.5 rim

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the second number is the percentage of the first eg 205/50 means 50% of 205, which is 102.5mm.

45% is 92.25 so you have lost 10mm of sidewall.

 

HTH.

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I would have interjected here that there's a link to a wheel and tyre bible in the wiki, which includes a calculator to work out all this kind of thing.

 

But as the wiki's semi-dead at the moment Lisa's link will do the job. :lol:

 

This link for the terminally geeky though - http://www.carbibles.com/tyre_bible.html

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I would have interjected here that there's a link to a wheel and tyre bible in the wiki, which includes a calculator to work out all this kind of thing.

But as the wiki's semi-dead at the moment Lisa's link will do the job. :lol:

 

This link for the terminally geeky though - http://www.carbibles.com/tyre_bible.html

 

Where's the fun in looking it up on a Wiki? Takes all the fun out of being opinionated it does! :D

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