----- Original Message -----
From: David Hill <Davhill@btinternet.com>
To: MG List <mgs@autox.team.net>
Sent: Thursday, July 27, 2000 3:49 PM
Subject: Smoke & Oil, Etc,On list reply
> This is to Richard, but I've put it on-list because I got an undeliverable
> mail kick back.
> Apologies for using bandwidth
>
> Hi, Richard.
>
> I'm sorry but I don't subscribe to this view. I've had any number of
people
> talking about putting big carbs on cars and just as many moaning at the
> results.
>
> The bottom line is that petrol engines work best at a thing called the
> stochiometric ratio of air to fuel. This is about 13.75:1 (I think), no
> matter what carbs are used. The error people do make is to think that big
> carbs=power and this isn't necessarily true. Overcarbing an engine,
without
> head work, changes to the cam profile, exhaust and ignition advance curve
> can drop the inlet gas speed so much that the fuel doesn't atomise =
really
> rough running. Equally, too much tune for road use makes an engine a pain
at
> anything less than about 1/2 throttle.
>
> To me, the only valid part is, 'push the car harder'.
>
> Right, sermon over.
>
> I think that one of two things has occurred, if your problem is indeed in
> the block...
>
> (1) The previous owner did cause a wear ridge and higher revs have caused
a
> ring to touch and break.
>
> (2) There was a ring which was already on its way home and your using the
> car harder has found the flaw.
>
> In the first event, sufficient revs to cause a rod to 'stretch' would
> probably be very, very high-well past the point of valve or even contact
> points bounce, when more revs would just make more noise, not more power.
> Also, why only one cylinder?
>
> In (2), the car wouldn't have too do too much work for an existing flaw to
> travel.
>
> In any case, assuming you haven't been seeing how far into the red the
tach
> needle will go, you remain blameless. An MGB may be a Morris Oxford Sports
> but the B-Series motor is a tough old lump which can take a lot of
> punishment-ask the racers.
>
> I drive my car hard from time to time, in the knowledge that it has good
oil
> pressure and flow, cools itself and makes no untoward noises. That said, I
> temper my enthusiasm with the knowledge that it is pushing 29 years of age
> and can't be expected to rev like an undersquare, Japanese motor.
>
> I hope you will mail me with the results of your car's post-mortem, as and
> when you do it.
>
> Cheers,
>
> Dave H.
>
>
>
> Can I Telework for you? See what I do, at...
> http://www.angelfire.com/biz4/davtel/index.html
> Troubled by a phobia? Know someone who has one? Go to...
> http://www.psychomotor.co.uk
>
>
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