Bud,
Stu,
According to Carl Cederstrand's booklet on rear end conversions, a Michelin
165 x 15, ZX tire turns 813 revs per mile. (He doesn't specify tire
pressure.) Multiplying by 4.3, the rear end ratio, results in 3496
driveshaft revs per mile. Since the transmission ratio is 1:1 in fourth
gear and since 60 mph is a mile a minute, the engine RPM at 60 MPH should be
3496.
If Stu has a Datsun five speed or some other gearing, then perhaps 3250 RPM
at 65 MPH is possible. It is also possible that speedometers and/or tachs
are in error.
Ben
54 TF 1500
----- Original Message -----
From: Bud Krueger <bkrueger@ici.net>
To: Stuart Keen <simbafish@home.com>
Cc: MG T Digest <mg-t@autox.team.net>
Sent: Sunday, October 22, 2000 5:19 PM
Subject: Re: Valve Cover Cap
> Stu,
>
> There's little question that your cap wasn't missing for very long.
The oil
> spray would have hit some hot surfaces and brought it to your attention.
>
> My big question is --- What sort of gearing (and power) is allowing
you to be
> running at 65 mph at 3250 rpm? With 4.3 gears in my 52TD I'm at about
3700 at 60
> mph (running 165-15 Dunlop SP-20 tires).
>
>
> Stuart Keen wrote:
>
> > I'm looking for the voice of experience. The scenario is this:
> >
> > I filled up the engine sump with oil just before I left and put on the
> > valve cover cap (I know this is fact). I drove 75 miles to Tampa to an
> > all British Car Show car show.
> >
> > At the show I had both halves of the bonnet raised so viewers/judges
> > could observe the engine compartment. I didn't observe anything was
> > missing; but then, I wasn't suspicious.
> >
> > After the show, I closed the bonnet and drove home at a steady 65 mph
> > (3250 rpm). No noticeable smell of oil burning.
> >
> > This morning I raised the bonnet on the left side. I noticed two VERY
> > small "runs" or trickle of oil on the underside. I immediately noticed
> > the cap to the valve cover was missing!
> >
> > Further inspection showed a slight (not heavy) mist of oil on the
battery.
> >
> > My question is this. How much oil would bounce/spray out of the valve
> > cover filler opening when the engine is running? Since I see very light
> > evidence of oil external to the cover, I am thinking that the cap must
> > have come off just before I arrived home. However, perhaps my thinking
> > is wrong. Maybe not much oil would spray out in any situation. I don't
> > know. If very little oil would spray out during the 75 mile ride home,
> > then that would mean my search for the cap would be in vain. I have
> > already search the road traveled for a distance of 4 miles.
> >
> > Has anyone driven any distance with the valve cap off? What was the
> > effect over what period of time. The filler hole on my valve cover is
> > about 2.5 inches in diameter and is raised about half an inch from the
surface.
> >
> > Stu Keen
> > Venice, FL
> > 51 MGTD MkII
>
> --
> Bud Krueger
> http://home.ici.net/~bkrueger/
> 52TD
> 77MGB
>
>
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