mgs
[Top] [All Lists]

Re: MGB engine and transmission in an MGA

To: mgs@autox.team.net
Subject: Re: MGB engine and transmission in an MGA
From: WSpohn4@aol.com
Date: Sun, 13 Jan 2002 02:03:10 EST
In a message dated 1/12/02 8:56:58 PM Pacific Standard Time, shaws@mlcltd.com 
writes:


> >With your recommendation, you have a car with less performance than a stock
> >MGA. With all due respect, that is NOT a direction in which I am interested
> >in heading!
> >
> >Bill
> 
> Bill, That is NOT TRUE.  The modifications I have done to my car make 
> 

That's not the point. By using the lower diff ratio, the car is slower 
through the gears than it would be with the regular ratio. The fact that you 
may have tuned it is irrelevant.

If you are saying that it is fast enough for you, that's very nice for you - 
but it would be a quicker accelerating car if it had a lower ratio.

If you are worried about  first gear being too low ( about which I would 
disagree) you can always fit a close ratio gear set. The admittedly low 1st 
gear is perfectly acceptable with a 4.3 diff ratio, even with a tuned MGB 
engine, though I would agree that for any sort of spirited driving not 
involving a lot of stop and go, the CR set is much nicer, and MUCH faster, 
given a 4.55 diff.

Your assertion that using a 4.3 instead of a 3.9 diff "makes a slower car 
that is not able to optimally use the additional power present in the 1800 
engine" is specious.

If, as you imply, you have traction problems with a 4.3 diff, the answer lies 
not in fitting a 'longer' ratio than the MGA, or indeed than an MGB, came 
with (given the 15" wheel size of the 'A'), but in giving attention to 
methods of improving the traction.

I base this on my experience using tuned MGB engines with twin 1 3/4" SUs, a 
supercharger, an HRG head with SUs, and the same head with twin Webers, all 
on the street, with a variety of diff ratios from 3.9 to 4.88, and wheels 
from 13" to 15", all on the street.  All of which is confirmed by my racing 
experience.

You indicate a preference for the all synchro transmission (I prefer the 
feel, and the CR ratios of the early box, but can understand those who like 
the later one - I use both). The comments would be essentially the same for 
that box, although the ratios vary from the early box slightly.

Bill

///
///  mgs@autox.team.net mailing list
///  or try http://www.team.net/cgi-bin/majorcool
///


<Prev in Thread] Current Thread [Next in Thread>