Hi Russell,
Our Ghia will do between 135-140mph on a long straight. We calculate this via gear ratios, tire diameter, and RPM. and the fact we stay up with the competition. Our next race is early March, SVRA Road Atlanta.
You want to keep as much weight within the wheelbase as you can. An important modification is adding caster shims under the front lower torsion tube. You couldn't do this on your B and it makes all the difference. The swing axle is not the most stable of rear suspensions and tends to steer your car from the wrong end. We have the 4-joint rear suspension and run zero toe. A swing axle tends to rise and squat and you accelerate and brake. At the least, you need good stiff spring plate bushings.
We always ran a sheet metal airdam in HSR but SVRA won't allow it. At our first Road Atlanta race without it, We really couldn't tell much difference.
A final tip is with some real power, lower the suspension one to two inches.
email me at fjcamper.dot kg at gmail dot com with photos and we can talk aerodynamics.
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