10-09-2020, 08:59 PM
There is something seriously amiss with a lightweight special that is not capable of more then 45mph I don't believe the gearing is going to be it. It is very hard to answer the questions without seeing the car in the flesh and knowing what has been done to it, which Duncan appears not to know either, first stop would be ignition timing and mixture. You mentioned the exhaust system what is on the car, is it seriously restrictive which if so may be the problem? The manifold is, as on all sevens, dreadful but that should not stop it from achieving a far better top speed than quoted.
Black Art Enthusiast