I had a look at Lawrie's page - lots of interesting stuff - but particularly
looked at the B convertible he modified, and thought that it was much as I
would have done it (which is a real compliment, at least in my eyes, as there
are
so many wrong-headed 'conversions out there).
There were only 2 things I'd have done differently, in fact (well, I might
not have bothered with the rear tube shocks and I would probably have gone with
a non-synch close ratio box, but those are minor).
The seat covers don't ring my chimes, but that's no big deal - aesthetic
judgements are always so subjective.
But the other thing I'd have done was to fit HS6 carbs (I applaud the use of
SUs instead of the obligatory Weber - it denotes someone that is out to get
the best performance, not the most ooh/ahh factor). I note Lawrie's statement
that he chose the stock size HIF4s as he wanted to accentuate torque rather
than
top end power.
That's the bit I question. Having looked at quite a few dyno tests (none of
which fall readily to hand to support my thesis), my recollection is that the 1
3/4" carbs provide higher top end power, _without_the torque figures in the
mid-range falling below what you get with the smaller carbs. In other words you
get just as much torque, but have more high end power, should you ever run
the engine above 5000 or so.
This is not the case, as I recall, with 2" SU's - I think they are weaker low
down and stronger up where most street engines will never tread in any case.
Can anyone comment (I prefer data to uninformed guesses here) about the
relative torque with 1 1/2 and 1 3/4 carbs? Obviously the actual figures
achieved
are dependent on cam, compression etc., it's the relative relationship I'd like
to investigate.
Bill
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