FC wheels on CM FF....Go!

[CM/FFdriver]

Hello All,

I've been thinking about this after the post about not being able to get rain tires in the bias ply anymore for the FF cars so what do you all think About?

FC wheels they are about the same price as the FF wheels, we already using the FC front tire and the rear tire would be 3/4 wider. So...I don't have any FC wheels but I'm betting wheel/tire combo is going to be a little heavier and with the corner speed could be up but not over all speed it maybe a wash. Profile of the cantilever and the rear tires of the FC are the same looking from the rear of both cars, let me give you some details, we had an event 2 weeks ago and a FC showed up and I was taking a lot of measurements and the FC rear tires are more squared off so thats where the 3/4 wider (a total of 1.5 in) comes from.

There is so much more to think about here but I was just thinking and thought I would throw this out there.

I couldn't help thinking of the wide variety of tires we could choose from R20's, R35's, R45's and R60's and yes rain tires. Just something to think about.

Ben

[-pru-]

Ben,

Given the long term uncertainty of a soft (i.e. R25/R20) FF rear, I like the proposal. From a cost/modification point of view, it seems pretty straightforward. Like you've noted, most (if not all) of those running the FF in CM are using the FC (7") front (on a 5.5" wheel), so acquiring/fitting a pair of 8" rear wheels (initially) would be all that is necessary to move forward. Again, like you've noted, the 8" rear opens up numerous tire selection options.

Time for a letter to the SEB (http://crbscca.com/) ?

Take care,

[TedV]

What would be the number of cars that can not move the inner rim lip location 1.25" in because of suspension interference? Some cars were ran as both FF and FC so no problem there. Others built to only FF might use that location close to rim and tire as a suspension point. Why am I thinking DB1 might have an issue?

[-pru-]

Why am I thinking DB1 might have an issue?

Photo of rear wheel of DB1 as a FC (DB3):



From the following ad:

1985 Swift DB3 Formula Continental For Sale
https://r.tapatalk.com/shareLink/top...ink_source=app

[tlracer]

Biggest factor is going to be the offset, from the inner rim to the drive face of the wheel, and whether this gives clearance on the upright and rocker/wishbone (A-arm) bearings.

I would think there are very few cars where the rear uprights are different between the FF and FC versions?

[R. Pare]

Do the CM rules allow the wider FC wheels?

[lowside67]

Do the CM rules allow the wider FC wheels?

Not currently - that is the point of this thread, to gauge interest and garner support I imagine.

-Mark

[TedV]

Do the CM rules allow the wider FC wheels?

Not at this time. Cars must meet road race rules except for CM has an open tire rule.

DB1 issue may have been from needing more camber for radials or maybe some cantilever tires took an offset towards the upright and rubbed. I would think any car made for both FC and FF wouldn't have an issue. Maybe some of the earlier FF only cars?

The FC rear size is also used on some FA fronts so the 22x9 or 22x8 might have more sales than the FF bias rear. Conversation with Hoosier and Avon might be in order. Hmm, who makes the better FC sized tire for autocross?

[Earley Motorsports]

How about grooving some slicks? Just asking.