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David Winn

(2 posts)

11/20/2017 10:44PM

Main British Car:

Suggested gears for a ford 9 inch 3.55 in a 1974 Jensen Healey
Posted by: dlwharleyman
Date: May 25, 2018 11:48AM

My 74 Jensen Healey has a 1988 TPI (tuned port injection) 350 and a 700R4 automatic transmission, with a Ford 9 inch rear end with 3.55 gears. The rear tires are P205/60 R14 and look to be around 23" tall. The TPI 350 has a tons of low end torque. The previous owner used to drag race it and won some races. Needless to say, with the high torque and 3.55 gears, it takes very little gas for the tires to spin. Feels like I can hit the gas at 50 to 60 and have tire spin. Looking at putting lower gears in to make more highway friendly, but would still like some good torque for in town and mountain driving. Recommendations?

Jim Stabe
Jim Stabe
San Diego, Ca
(746 posts)

02/28/2009 10:01AM

Main British Car:
1966 MGB Roadster 350 LT1 Chevy

authors avatar
Re: Suggested gears for a ford 9 inch 3.55 in a 1974 Jensen Healey
Posted by: Jim Stabe
Date: May 25, 2018 12:25PM

Those engines are stump pullers especially with an automatic. I would try to get a larger tire on the car for better traction as well as lower cruising rpm. With OD you won't need a super tall gear, maybe a 3.23 or so. Try to get the rpm at 70 mph under 2000, that seems to be a sweet spot for mileage.

Art Gertz
Winchester, CA.
(3009 posts)

04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: Suggested gears for a ford 9 inch 3.55 in a 1974 Jensen Healey
Posted by: roverman
Date: May 30, 2018 01:52PM

Got posi ? With the Huffaker rear glass fenders you get 12" wide wheelwell,(move shock). LT1 is all iron ? If so, around 60% +/- on front, weight bias ? Your size tires pretty hopeless for stoplight grandprix... Drag shocks on the front = bumpy street ride. Maybe finesse the instant center of rear suspension ? You could try some sticky slicks, to push that smile further back on your face ? Good Luck, art.

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