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Re: Midget/Sprite revs

To: british-cars@autox.team.net
Subject: Re: Midget/Sprite revs
From: jesup@cbmvax.cbm.commodore.com (Randell Jesup)
Date: Sat, 21 Nov 92 17:20:30 EST
>>>> First, how fast is it safe to run constantly on the highway in this car?
>(Keep in mind that it's a 3-main engine and the final drive translates to
>about 3700-4000 RPM at 65 MPH.  I'm just wondering if anyone has any
>suggestion on the upper limit to engine speed for long drives.<<<

>>>> Hmm - I'm also very interested in any recommendations from the list.
>My '66 Midget seems to indicate rpm of nearly 5000 at 65mph.... <<<

        All Sprites/Midgets until '67 (or so) had stock 4.22 rears.  Later
A-series cars had 3.9 rears, and I ignore the triumph-powered midgets... ;-)

        A 4.22 rear makes these light, low-powered cars feel far faster
than a stopwatch would indicate.  It also gives them good low-speed performance
which drops off a fair bit by the time you get to 3rd gear.  The downside is
major revs on highways, and an overdrive was never offered.

        If you want real fun, have a sprite with a bad 4th gear for your
only car.  I did that for years in high school and college.  A 4.22 sprite
will turn ~1000rpm/10mph in 3rd.  Driving at 55-60 on the highway meant a
steady 5500-6000 rpm for hours (and this in a 1098CC engine - I'm glad it
wasn't the 1098CG).  Yellow-line started at 5500, red at 6000 (the 1098 is a
much longer stroke engine than the 1275, which is under-square).

        That car took that (burning 1 quart oil per 100 miles the whole time)
for 3-4 years, before finally relegated to parts car after blowing a flexible
brake hose (and then being stolen with a tow-bar after only a few parts had
been used!)  It may well have contributed to the valve job it needed at one
point, though - two burnt/chipped exhausts, 1 chipped intake, 1 bent intake,
though the final damage apparently was a roll-start with a bad condensor.  Even
like that it would do 45-50mph limping back to college and the RPI auto shop.
(That was a "fun" trip - 0-3 degrees F outside, drafty sprite, and the engine
never got warm enough to make the temp needle move - 1098's had it mounted in
the radiator, and a 3 hour trip.)

        Randell
p.s.  Cpt. Bobwrench, you still have all my Sprite books/manuals/catalogs...
4.5 years and counting...



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