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Old 03-21-2013, 08:40 PM   #1
0311fastco
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Transmission and Gears!

Im gonna be running a 454 40 over hydraulic cam, Im thinking of going with a
700R4 what is your guys knowlege for best performance for street and highway to have fun and cruise, so I dont have to go 55 on the freeway, ha.
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Old 03-21-2013, 10:46 PM   #2
68350
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Re: Transmission and Gears!

i have a built th400 and 3.42 gears in my 72. The stall in the tranny is 2800 and at 65 mph it just gets to lockup. It cruises really well on the highway.
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68 Chevy CST/10, 50th Anniversary, 327/th400, 373 posi, buckets
68 GMC Shortbox Stepside, 402/th400, Tilt, Tach, Bucket Seats, 3.08 Positraction
69 Chevy Camaro SS, 383, 4 speed, positraction
70 Chevy El Camino SS396, Triple Black, 454/th400, Tach
70 Chevy Shortbox Stepside 4x4, 350/th350, Tilt, Tach, Cab Lights, Bumper Guards, Tow Hooks
70 Chevy 3/4 Longbox, 350/auto, 70k, SURVIVOR
71 Chevy Blazer, CST, 350/auto
71 GMC Sierra K2500, 454, 4 speed, 4.10 posi, 37s
71 Custom/30, Open Road, 350/th400, tilt
72 Chevy Shortbox Fleetside, 496 Stroker/th400, Tilt, Tach, Bucket Seats, 3.42 Posi
72 GMC Sierra Grande 2500. 427/th400, tilt, a/c, tool and stowage, buckets/console, 3.54 posi
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Old 03-22-2013, 07:21 AM   #3
MARKDTN
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Re: Transmission and Gears!

What size tires are you running?
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Old 03-22-2013, 08:46 AM   #4
68350
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Re: Transmission and Gears!

Let me double check but I think 295/65/15 in the back
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68 Chevy CST/10, 50th Anniversary, 327/th400, 373 posi, buckets
68 GMC Shortbox Stepside, 402/th400, Tilt, Tach, Bucket Seats, 3.08 Positraction
69 Chevy Camaro SS, 383, 4 speed, positraction
70 Chevy El Camino SS396, Triple Black, 454/th400, Tach
70 Chevy Shortbox Stepside 4x4, 350/th350, Tilt, Tach, Cab Lights, Bumper Guards, Tow Hooks
70 Chevy 3/4 Longbox, 350/auto, 70k, SURVIVOR
71 Chevy Blazer, CST, 350/auto
71 GMC Sierra K2500, 454, 4 speed, 4.10 posi, 37s
71 Custom/30, Open Road, 350/th400, tilt
72 Chevy Shortbox Fleetside, 496 Stroker/th400, Tilt, Tach, Bucket Seats, 3.42 Posi
72 GMC Sierra Grande 2500. 427/th400, tilt, a/c, tool and stowage, buckets/console, 3.54 posi
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Old 03-23-2013, 12:50 PM   #5
Mike C
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Re: Transmission and Gears!

That's a 30" tall tire. Is this a fuel injected motor? With the TH700 I would run at least 4.10 if not 4.56. 30" tire with 4.10 at 70 mph = 2250 rpm and with 4.56 = 2500 rpm. Fuel injection would allow it to work better at the lower rpm than a carb, the cam you choose will also make a difference. With a .050 duration of 210 degrees or less the 4.10 would be my choice. Also allowing you higher speed when towing if you stay in 3rd gear which I would recommend with the 700 and any real weight (5000# or more). With a .050 duration of 220 degrees or more, I'd go with the 4.56 and something in the middle either gear would probably work well.
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