17x9 and 245/40 RE-71 combo for ND Club

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ChristopherH060
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Joined: Sun Mar 11, 2018 1:35 pm

17x9 and 245/40 RE-71 combo for ND Club

Post by ChristopherH060 »

Is anyone running this combo and if so:
- what suspension set up
- how much rub
- how much fender roll is required

Thanks-
Brian
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Re: 17x9 and 245/40 RE-71 combo for ND Club

Post by Brian »

Common Autocross fitment (STR class in particular). Pics of this setup throughout the gallery here. If you go to the product description for most of the 17x9 in our store, that's the picture you see is 245/40. For example, Charcoal 6UL 17x9, click here.

Below is one of those shots, 245/40/17 requires fender roll front and rear. Our Ohlins coilovers, adjusted heights of about 13.25 inch center of wheel up to fender lip. That does rub fender liner at full lock.
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Charcoal-6UL-ND245.jpg
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
ChristopherH060
Posts: 13
Joined: Sun Mar 11, 2018 1:35 pm

Re: 17x9 and 245/40 RE-71 combo for ND Club

Post by ChristopherH060 »

Thanks Brian, I know we exchanged emails on this a while back when I was just getting started.

I'm running STR and aside from my driver needs some work, but I'm trying to do everything else I can to close the gap on the S2000 at the top of my class. I'm currently running your Hypergrams 17x8 with Dunlop ZIIs in 235/40.
I'm O.K. with the fender roll.

Is it worth it to switch to the 17x9 and 245/40s (i.e. is it potentially worth 1-sec)?

Currently running sways F/R, RS springs, GWR header, OFT stage 2, 17x8 Hyrpergrams wrapped in 235/40 ZIIs.
Brian
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Re: 17x9 and 245/40 RE-71 combo for ND Club

Post by Brian »

Yes, on 60 second course the change from 8 inch wide wheel to 9 inch wheel is easily over 1 second advantage.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
ChristopherH060
Posts: 13
Joined: Sun Mar 11, 2018 1:35 pm

Re: 17x9 and 245/40 RE-71 combo for ND Club

Post by ChristopherH060 »

Thanks for the insight. Last (I hope question). I'm running 17x8 Hypergrams weighing in at 16.3lbs with Start Spec ZII 235/40. The ZIIs have a tread width of 8.4".
I'm about to upgrade to the 6ULs (15.4lbs) and RE-71 in 245/40, but the tread width is only 8.6". I'll give the RE-71 an edge in performance, but 0.2" difference in tread on the pavement doesn't seem like much.
What am I missing....(I know that's potentially a long list)?
Brian
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Posts: 11308
Joined: Tue Feb 15, 2005 11:44 am
Location: San Diego CA
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Re: 17x9 and 245/40 RE-71 combo for ND Club

Post by Brian »

Sidewall support and Compound trumps. The new Dunlop is very good, but the kings of STR continue to be Rival S and RE71R. I have slight preference for the Rivals, seem to work best with my driving style. Support the sidewall with extra inch of rim width and more of that tread actually stays on the ground in the turns.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
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