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Re: lbc questions...

To: british-cars@autox.team.net
Subject: Re: lbc questions...
From: fickes@taurus.apple.com (Stan Fickes)
Date: Thu, 20 Oct 1994 10:00:36 -0800
Ray asked:
>If the collective net wisdom (I like the concept of net
>wisdom--you add up the good opinions and the bad ones, to get the net
>wisdom--but I digress) is that the carbs were improperly rebuilt, and I
>have to start over, I am tempted to have the larger set rebuilt for a
>performance gain.  The question is, would there really be a significant
>gain?  If I am not mistaken, the original carbs are 1-1/8 inch, and the
>other set is 1-1/4 inch from a later Spridget.

[Only a partial answer...]
Going from 1.125" to 1.25" is a gain of nearly 25% in throttle area, which
is certainly nothing to sniff at.  However, unless the rest of the engine
is ready for the better breathing (yours does sound like a good setup) you
won't necessarily gain, and you could lose performance.  For example, if
you went to a REALLY large throat, you would reduce the air velocity to
almost nothing, and would lose the venturi effectiveness.  Now if you
weren't worried about originality, a 1275 would look real good under the
bonnet...

I'm not sure I'm the best one to comment on rebuild quality; I currently
have a real problem with my rear carb.  It's turned about 12 flats richer
than the front.  Yes, I have carefully balanced, checked the pistons, etc.
but suspect a shaft bushing problem or a clogged jet.  Maybe I'll get to it
this weekend...
sf

Stan Fickes                             British Cars
Wireless Communication Technologies     1951 MGTD
Advanced Technology Group               1965 Austin-Healey Sprite
Apple Computer, Inc.
408 974-7653





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