Originally Posted by 80camaroguy
would that gear be good for gget up and gobehind the 4 speed. or even posibly a 5 speed
The Saginaw will not take much abuse.
Shoot for a 10.0:1 first gear final drive ratio and a close ratio gearbox.
This would be my choice for you if you're bucks-up....
Richmond Gear 7021710A Richmond 5-Speed Street Transmissions
Richmond Gear 49-0001-1 Richmond Gear GM 10-Bolt Ring & Pinion Sets
Match the 3.28 first gear of the 5-speed with a 3.08 rear gear and find a first gear final drive ratio of 10.1:1.
5th gear is 1:1, so with the 3.08 rear gear and a 28" tire, the cruising rpm's at 60 miles per hour would be 2,250. Cam the motor accordingly. If you screw some fosdick long duration cam into the motor, you'll be steppin' on your.....toe.
If you're not bucks-up, try to locate a '66-'74 Muncie 4-speed with a 2.52 first gear.
Mate it with the 3.54 rear gear suggested by big gear head for a first gear final drive of 8.6:1 or use a 3.73 rear gear for a first gear final drive of 9.4:1.
Muncie Transmission Id and ratio guide