Fred,
You didn't include one crucial piece of information: what size tires?
At the risk of sounding like an engineer (I am), you can use the following
formula to figure out road speed if you know RPM, axle ratio, and tire
height (measured from the ground to the top of the tire).
Speed (MPH) =(Tire Height (inches) x Revs (RPM) x Pi (3.14))
----------------------------------------------------------------
divided by: ( Axle ratio x 1056 (inches/mph))
The stock tire on a 13" rim is approximately 22" tall. Plugging in that
number gives approximately 74.4 mph.
Still pretty good for a 35 year old Sprite!
Jim
> -----Original Message-----
> From: Fred Krampits [SMTP:fred@hprrc725.rose.hp.com]
> Sent: Monday, June 01, 1998 10:57 AM
> To: spridgets@autox.team.net
> Cc: Lawrie@britcars.com
> Subject: Beautiful Saturday drive, bad sunburn and couple of
> questions
>
> I've got about 200 mile on my Midget since all the engine and tranny
> work was done, and finally decided to take a afternoon ride thru the
> mountains. Lawrie Alexander recommended HWY 49 between Rescue & Auburn
> CA. Well worth the ride, numerous hairpin turns, my car attracted so
> much attention from other drivers I'm surprized nobody drove off the
> mountain. From Auburn to Roseville (Home) I took I-80, was able to hold
> my own in the center lane, got it to 4800 rpms without even pushing it.
>
> Now comes my questions, I have a 1098CG, stock ribcase, 422 rear end,
> how fast was I going at 4800 rpms? My speedometer has been on the bottom
> of the list of things to fix, it kinda erratic, it did register close to
> 90 when I was at 4800 rpms in 4th. I doubt it's accuracy. The next
> morning I woke to a flat on my right front wheel, no tire damage
> probably a pinched tube from the wire wheel spokes and nipples being put
> to the test. Anybody ever use the rim bands Moss sells?
>
> Only real drawback of the trip was just as when I was in Hawaii, I did
> not realize how bad the thinning mane was being sunburned until it was
> too late, I got a mild second degree sunburn on the scalp which I'm
> going to be paying for all week. So much for my thrill of watching my
> wife grabbing the Sprite grab handle I fitted, hanging on for life as I
> nailed those hairpin turns.
>
> Fred
> 1963 Midget MK I 1098CG
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