Re: 16" on 90 coupe

[Glenn Lawton <lawtonglenn@gsmai.com>]

Grant Lenahan wrote:
> ...(1) Tire width/section and (2) wheel diameter. Your proposal, for 
> 225/50/16s increases BOTH.  They are unlikely to fit, and would 
> drastically alter your gearing anyway.  Calculate the total circumferance 
> to ID gearing changes, diameter and width to determine fit.

Ian Duff wrote:
> Non Coupe or 90-20v owners please note (and don't flame, er singe, me on
> 225/50 not fitting), the stock Coupe tahr size is 205/60-15, unlike the
> 90 seedan.



Grant:
I think Ian hit the nail on the head. The 20vCQ came with BIGGER tires 
than the 90 sedan, and therefore the gearing change is less than 1%

Section	Aspect	Wheel	Side	Side	Overall		
width	Ratio	Dia	Wall	Wall	Dia	Circum	
mm		inches	mm	inches	inches	inches	
205	60	15	123.0	4.8	24.7	77.55	100.0%
225	50	16	112.5	4.4	24.9	78.09	100.7%


Ian:
Most aftermarket 15" wheels are 7", most 16" are 7.5"
Original ET on the CQ is 45, I just bought 16x7.5x35.

If you put the 20mm wider tires on ET35, the inside of the tire would
move inboard by 20mm/2=10mm. If you change the offset by 10mm,
say from ET45 to ET35 (or ET37), then the inside wall of the tire
is kept at the stock location, and the outside wall moves towards
the fender lip by the entire 20mm.

I like the look of the Borbet C, $199ea at Tirerack. I cheaped
out and got the lookalike Motoring Exponents Zones from Discount
Tire Direct, for $139ea, with 225/50-16 P7000supersports $148ea.

I applied, but I don't think I am on the 20v list, how do I get subbed?

Glenn