I sent this off to the resident knower of all things british on the MG
list here is his response
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Date: 09/13/1998 7:08 PM
Received: 09/14/1998 12:30 PM
To: Larry Macy, firstname.lastname@example.org
Larry, you will have to re-mail this to them for me, I am not on their
Larry Macy wrote:
> This came from the Spridgets list. Can you help these poor forgotten
> souls that think a Sprite is a real car?? They've already been banned
> from the Healy list, and nobody seems to care about Midgets (even though
> the early T series are called Midgets). Just thought I'd ask?
> Larry Macy
> 78 Midget
> ---------------- Begin Forwarded Message ----------------
> Date: 9/12/98 7:05 PM
> Received: 9/13/98 12:25 AM
> From: Martyn Ridley, email@example.com
> To: Spridgets, firstname.lastname@example.org
> Summary: For those that skim read only!
> 1. What is rolling diameter for original Frog(BUG in US)eye Sprite?
A) The rolling diameter of the wheel will depend on if a radial ply, or
cross ply is fitted. The pressed steel wheels are the same as used on
millions of Austin A30, A35, and A40 Farina UK models. Infact to us the
car IS a A35 souped up a bit!! Size are 13" ventilated disc wheels, with
5.20 by 13 tubeless tyres originally. These are cross ply. Sitting, the
car tyre will be about 3 3/4" on the tyre, plus the 13" wheel, equates
to a rolling diameter of 20.5". The circumference is equal to pie-D,(
3.142 x 20.5) which gives a rolling distance of 64.5". For a 155 radial
ply, remove 3/4" from the diameter.
> 2. Name a modern BRITISH radial that will fit
A) 155 by 13", Michelin are the most popular, but Dunlop seem OK. As
many modern small cars use 13" wheels, tyres are no problem in the UK.
165 by 13 will fit, but look a bit fat.
> 3. Reply please!!!!!!!
A) This information is supplied by someone who sold his 1966 Midget
because he could not get out of it any more!!!!!!! Replaced by a 1952 MG
'YB' saloon.....heater and a roof.
( They can email me if they want to.)
> We seem to be spending a lot of time on this subject but to date I don't
> see that we are really getting anywhere. If I gauge the issues
> many of us are looking to find out what rubber me put on our various
> collection of beasts. I judge us to be in three camps; purists,
> functionalists, & go faster!.
> Purists seem to favour cross ply tyres, Functionalists, modern radials,
> go faster, what ever is quickest and stickiest.
> Unless anybody can correct me, the only cross ply tyres still out there
> (worth buying) are Dunlop's vintage race tyres (L or M series). Are
> vintage race tyres suitable for street use?
> As for go faster tyres, I am out of my league. I know that fitting Vega
> rims and race tyres is ultimate bur exactly what is best is not in my
> realm. Help anyone?
> So, now to us functionalists. We are looking for good, day to day tyre,
> that will fit on a 3.5 (disc), 4.0 (wire) or 4.5 in rim. In essence we
> would like to maintain the original rolling diameter (OK PURISTS!, what is
> the original rolling diameter?) and give us the benefits of modern
> technology (as those around us will have it and assume we do too!). I
> no problem with 165/70s if they fit on the 4.0 rim. Do they?, Safely?
> What if I only have the Frog's 3.5 disc wheels? Is there a 155/75?, or
> will a 175/70 or 175/60 that will fit? I know Dunlop does a 145/80, a
> 155/80 and a 165/70. Are there any REAL British mfgers out there that
> equivalent tyres? (Sorry, functionalist I may be, but putting yoko's or
> tyre cheep o cheepos is beneath me) Comments would be appreciated.
> It's the going, not the getting there, that's good.
> (Harry Chapin - Greyhound)
> ----------------- End Forwarded Message -----------------
> Larry B. Macy, Ph.D.
> System Manager/Administrator
> Neuropsychiatry Section
> Department of Psychiatry
> University of Pennsylvania
> 3400 Spruce St. - 10 Gates
> Philadelphia, PA 19104
> In a world without walls or fences, what use do we have for windows or
----------------- End Forwarded Message -----------------
Larry B. Macy, Ph.D.
Department of Psychiatry
University of Pennsylvania
3400 Spruce St. - 10 Gates
Philadelphia, PA 19104
Voice mail 215 662-2890