I have been lowering the rear spring rates on my cars. This allows me to raise the rear tire pressure, for a easier rolling race car.
It has helped the HP VW, and adds some straight speed to the Miata.( I have less data for the Miata)
I have dropped the VW springs from 550# to 350 and increased the pressure to mid 40s. The car pushes much easier this way and we had great straight speed last race. This car uses zero scrub for both ends and drum brakes that are very true and spin free.
The tires are the SRF, Good year slicks that we have a lot of. The little Hoosiers are faster but we dont have any sticky ones.
Next is to get the weight right on (50#), make a fuel box so that we can get all of the fuel, along with a pre filter. Still 100% glass and steel, and Mike is pretty close to the front in his first race.
I hope to have the HP lap record some time this winter. The Sebring track has been changed enough that it may not happen tho . maybe it will count in the new configuration.
All good. MM