Oddjob

Thanks for the sizes and p/n's. I've got a couple sets of BBS 17" wheels, E50 centers and E26 centers are getting too old to keep running (have already cracked one of the E26 cast mag centers). Looking at either replacing the centers with E87s, or going up to a full set of E88s. I really prefer the look of the 18" vs the 17's, but have to decide if the cost of full wheels (centers and rim halves) and 18 tires, compared to just getting 17" centers for my existing rims, is worth it.

951and944S

Seems that the trend is smaller diameter wheels.
IIRC, Poeltl is running 15" rears on SP3 S2 which helps lower gearing without expense of custom ring and pinion or 2-4/5 gears.
Going from stock 16" to 17 seems doable since, in R7, there are still tires that are equal to or barely larger diameter than the 16s.but 18s are + 1" diameter and +4" in circumference.

Going 18 = Heavier wheel + larger dia. tire + more expensive per unit....seems like a no brainer.?

T

Oddjob

I agree, but aesthetics has something to do with it. If the car looks good, it's worth at least a second a lap, right...?

When Hoosier came out with the 275/35/15 (23.0" diam), several years ago, there has been the trend to use them for the gearing. Buckley had custom wheels made, which are now real common on the E class SC's and 3.2 Carreras. I recall one 944T running on 15" BBS wheels in E class up to a couple years ago, Kansas City area. He was selling them on here not too long ago. Hard to find 15's that fit over the front calipers (small brembos), impossible over the 928S4s. So stagger is the only option there. I did hear that Poeltl did or was going to try the 15's on the rear over at Road America last year. He used to run 18's, did you hear or see that he is on the 15's this year?

Was a rule proposal a few years back wanting to limit tire diameter difference, so the small diameter whl/tires could not be used to significantly alter the final drive ratio - so it is generally believed to a noticeable advantage. The rule wasn't adopted.

Hoosier has a lot of low profile options, the 285/30/18 is 24.9", the 275/35/17 is 24.7" vs the 245/45/16 at 24.4". So you do lose just a little gearing with those, but not like running the 275/40/17 which is over an inch taller.

And gearing preference has a lot to do with track - my home track might be the only track in the US where the stock tall 951 gearing is a benefit. S2 gearing, or even shorter rear tire diameter would hurt me there (would add 2 additional upshifts/downshifts per lap). Absolutely agree that going with a taller rear tire is a detriment probably every where else. Although I did try running Road America with taller hear tires (the 275/40/17 Hankooks) to see if it helped shift points. Stayed in 4th on the straights, just barely didn't need to catch 5th.

DasSilberWedge

Sorry but.. MOAR E88!

PF

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PF

Pauls door decals look better in action👌