Thread: Budget 350 build questions

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I too have worried over mpg for a '29 roadster in the building stage with a 0.030" bored 350 with a Crane street cam, tube headers, Edelbrock Performer and 1.60 ratio rockers. After a lot of research I have settled on a 3.50 ratio rear and a beefed up 700R4 in the hope of getting 20+ mpg. Folks tell me that is iffy at best but yet Corvettes get about 26 mpg with a 700R4 and 2.90 ratio or thereabouts. As yet the car is not on the street so I do not know if I will get 20 mpg on the Interstate, but that overdrive gear should give good mileage at 65 mph and yet the low gear should give tire burning performance. Note that the 700R4 is said to require some beefing up for engines over 300 HP (???) so I bought an upgraded 700R4 from the "Eat My Shift" folks in Florida. You need to play around with some on-line gear ratio-rpm programs to figure out your rpm range and rear ratio. Take a look at this site:

http://home.tampabay.rr.com/1bking/c...calculator.htm

Don Shillady
Retired Scientist/teen rodder