Okay, so with my fancy schmancy new computer and op-sys and software I have
done another minor boo-boo and gone and responded to James privately rather
than back to the list. Thankfully, James was alert enough to send his
response to the list anyway. So I am hereby forwarding my earlier message
to the list (just 'cause I thought the full length version was a little
humorus). So now you get to be confused with the first message last.
[begin forwarded message]
>Date: Wed, 16 Feb 2000 07:27:58 -0600
>To: James Nazarian Jr <James.Nazarian@Colorado.EDU>
>From: Barney Gaylord <barneymg@ntsource.com>
>Subject: Re: Tire question for engineers
>
>James,
>
>At 05:00 PM 2/15/2000 -0700, you wrote:
>>.... The V8 is going in a '71BGT .... the car will be the absolute
minumum of street legality that I can pull off. .... but fact of the matter
is it will be a driver and will be on the roads a lot more than on the
track. Also I don't drive slow so I don't want to compromise. ....
>
>Okay, so hang all other parameters, and you have the race tires nailed
down (slicks), and now you just want tires that haul ass on the street.
>
>First rule of thumb: If it's more then 40 horsepower inch of tread width
you're screwed on all counts no matter what kind of rubber compoumd it has.
>
>Second rule of thumb, If the tires are more than 8" wide on a 2000 pound
car they won't warm up quick enough to be fully effective at autocrossing,
so don't get too carried away with extra width.
>
>First obvious implication: The combination of ROT1 and ROT2 implies that
anything more than 320 horsepower in an MG in ludricus. I would extend a
rather rash assumption and guess that this will not be the case.
>
>First obvious conclusion: As you are absolutely determined that you
"don't want to compromise", you should absolutely run treaded racing tires
on the street.
>
>Considering that you seem well bound (and well founded) to use 15"
diameter wheels and tires for street use as well as racing, you may like to
know that there is only one tire in the factory in the entire world that
makes a race tire in the 195-60-15 or 195-50-15 sizes, that being the
Yokohama A008RS road race tire (but not the A008RS-II autocross tire).
Other race tire makers do 15" race tires in 205 or wider sizes for 15"
wheels, but not narrower sizes. I use the A008RS tires on my MGA for
autocross, but only because such width is already too wide for the stock
wheel width that I am compelled to use in Stock class. Otherwise the
A008RS-II is better through the harsh turns, and other companies make
similar tires, so you logically don't want to use what I do.
>
>Second obvious implication: Following from the prior paragraph, you will
be using a minimum of 205 tire width as a matter of no other choice.
>
>Now as others on this list have stated, tires larger than 205 width will
not fit on a MGB without rather significantly flaring of the fenders (at
least the rear fenders). And as you yourself have stated, you don't want
to do that for appearance purposes (appearance to the insurance agent).
>
>Final obvious conclusion: You're stuck with the 205-15 tire size, and the
choice is just down to 60 series or lower profile. After that you can
collect all sorts of subjective opinions about which manufacturer makes the
"best" race tire. But none of this calls for you to do any exotic
calculation about tire size, because (with this car in particular) you end
up having worked yourself into a nitch where you don't have the liberty of
that choice anyway.
>
>$.015,
>
>Barney Gaylord
>1958 MGA with an attitude
> http://www.ntsource.com/~barneymg
[end forwarded message]
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