Best gear for 9.90

Tom Goldman · 04-03-2021, 01:27 PM

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 !

04-03-2021, 01:27 PM	#9
Tom Goldman VIP Member Join Date: Jan 2003 Location: Allentown,PA Posts: 2,478 Likes: 894 Liked 886 Times in 238 Posts	Re: Best gear for 9.90 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 ! __________________ Tom Goldman 1500 SG , 1506 STK