Originally Posted by Tom Goldman (Post 637969)

Like Charlie ,I run Select converters . I went to 4.56 gears from 4.29 in my Vette which weighs in at 2400# .
I picked up 2 mph with an increase of 250 trap rpm .
converter efficiency went from 10% slip to 5-6%. AND very importantly , the converter temperature dropped way down when coming off the stop.
Since Charlie's car is a '27 Roadster, one of the hardest cars to get MPH out of I'm not surprised by the lack of improvement in speed.
I would defiantly recommend 4.56 gears in your car.
Racers get too hung up on trap rpm's , if your engine is still pulling at the stripe ,let it eat !

Originally Posted by Charlie Yannetti (Post 641789)

In my combination, the gear change didn't seem to affect my reaction time.. I didn't change any numbers in the box..