Frank...my 2 cents worth: I use a narrowed 8" Ford rear end geared 3:00,
and find it to be excellent for general highway use. That puts me at ~2400
rpm at 70 mph using the overdrive of a stock MGB trans. Calculated top speed
is 140 mph, though I've never seen it. Of course, much depends on the
configuration of your motor, cam, etc.. The reason, I think, you found the
facrory V8s disappointing is they didn't really make any real power...being
rated at ~130 hp. It's actually hard to build one of these motors to have
that little power. Just putting a 4-barrel carb on the motor will make
significant additional power. Paying just a little attention to the
efficiency of the motor should easily get you 200 hp....I think you'll find
that to be a little less disappointing. ...ron howard
----------
>From: "Frank van Dalen" <F.vanDalen@lr.tudelft.nl>
>To: "mgb-v8" <mgb-v8@autox.team.net>
>Subject: Final drive ratios
>Date: Fri, Oct 29, 1999, 9:41 AM
>
>I am now well underway converting the front end of my '68 MGB to a RB spec
>(including the RB cross-member! -no offence intended Jim) and am starting to
>think ahead to what final drive ratio I should be using to match the Rover
>3500 engine and SD1 5-speed gear box.
>What I have in mind performance wise is a proper sports car that will
>accelerate quickly from curve to curve at speeds around 50 to 70 mph, but
>will cruise "comfortably" at 100 mph. I have driven two factory V-8s with
>the 3.07 final drive ratio, and found their acceleration a bit
>disappointing. On the other hand, most people seem to agree that the
>standard MGB's 3.9 ratio is unsuitable. What do you people recommend? What
>ratios have you tried and how did you like them? (don't forget to mention
>whether you built your car for sprint events or for the german motorways!)
>
>Thanks i.a.,
>
>Frank van Dalen
>
>
>
>
|