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Square wheels for S550 AX?

New to the forum, I'm an SCCA F-street (former S-197) AX driver looking for wheel recommendations for my new 2018 S550 PP1 car. Square is needed due to frequent rotations needed, but I'm stuck with +/-7mm offset due to SCCA rules. Thankfully, PP2 wheels/tires are legal because it's an option on this years model. PP1 is +45 front / +52.5 rear, but I'm unable to find PP2 offset specs, evidently not published yet - please post if you have them!

The least cost option is Ecoboost [email protected] ($400/set delivered) to run 275/35's, but I'd like 9-1/2"-10-1/2" needed to run 285/35's. Heck, 20X10's with taller 295/30's would be awesome to get higher speed in 2nd.

Any help you can help would be greatly appreciated!

TimK
 
If you're looking to run F street with PP2 wheels... you can't. The PP2 is classed in AS therefore none of its parts are legal for an FS car. You can't mix and match parts from cars on different model lines, so the Ecoboost stuff is also not legal for you car since it's in DS.

If you're going to run CAM, have at it :)
 
Thanks for your reply DocWalt; so much for wishful thinking.

Re-reading the rules, it says an option must be completed in whole to be legal. I'll take your word that the PP2 is A-Street. A question about the 19X9X45mm Ecoboost wheels: Why wouldn't they be legal? Same exact 19X9X45mm up front. Of course, the rears would be 0.5" narrower than factory 19X9.5X52.5MM. Though 0.5mm too far inboard (+/- 7mm is allowed), I don't see anyone caring. Worst case, a narrow spacer could be run to make up the difference. Your thoughts?
 
From the SCCA rulebook (below), width must be the same as standard. Do you think anyone would argue if the rears are 0.5" narrower than standard?


Any type wheel may be used provided it complies with the following:


A. It is the same width as standard and as installed it does not have an offset more than ±7.00 mm (±0.275") from a standard wheel for the car. The resultant change in track dimensions is allowed.

B. Wheel (rim) diameter may be increased or decreased 1" from the standard part. This change may be applied to the front, rear, or both axles.

Wheel spacers are permitted provided the resultant combination complies with the offset requirements of this Section. On vehicles supplied with an OE wheel spacer, the wheel spacer shall be considered as a part of the wheel. Wheel studs, lug nuts, valve stems (including pressure-relief types), and/or bolt length may be changed. Wheel bolts may be replaced with studs and nuts but the number of fasteners may not be changed. Tire pressure monitoring sensors may be removed.
 
If you're not doing SCCA national events nobody is likely to care. National events, yes, you could get in trouble with a protest for the 0.5" narrower wheels.

I agree that the rules are really restrictive on that kind of stuff, but it is what it is, for better or worse. :(
 
Thanks DocWalt,

The result of your input, I'm looking into CAM-C and STP as alternatives. To my surprise, 2017 track times between FS, CAM-C, and STP are much closer than expected:

F-Street 45 drivers, Fastest 56.5/61.6 Slowest 69.3/71.6

STP 18 drivers, Fastest 55.8/60.6 Slowest 63.1/71.9

CAM-C 53 drivers, Fastest 55.9/61.9 Slowest 63.1/71.9

Just gotta make a decision and pony up!
 
CAM-C is a great place to play, but I'm expecting CAM-C to get a LOT faster this year. STP isn't very popular nationally, mostly because CAM exists.

Where I live, street class is fairly popular (though F Street is all but dead) but CAM is exploding.
 

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