Need help..

[YahamaR1]

I am going to run a stock 454 in my 51"chevy
With the TH 400 .
I want a ford 9" axle.. What setup is the best
Option? What kind of ratio/gears,?..?
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[mr48chev]

Gear ratio needs to match what you intend to do with the truck. The big block will handle gears in the 2's or high 3' like 3.08's and not be a slouch on the bottom end allowing you to easily cruise at freeway speeds. 3.50 or 3.70 gears would give better acceleration but cost fuel mileage on the highway.

Suspension= what you prefer. Again what you intend to do with the truck determines that to some extent. If you plan to run at the drags the setup might be a bit different then if you just want to go to rod trots and show the truck or if you plan a lot of serous long (500+) road trips.

[YahamaR1]

Originally Posted by mr48chev

Gear ratio needs to match what you intend to do with the truck. The big block will handle gears in the 2's or high 3' like 3.08's and not be a slouch on the bottom end allowing you to easily cruise at freeway speeds. 3.50 or 3.70 gears would give better acceleration but cost fuel mileage on the highway.

Suspension= what you prefer. Again what you intend to do with the truck determines that to some extent. If you plan to run at the drags the setup might be a bit different then if you just want to go to rod trots and show the truck or if you plan a lot of serous long (500+) road trips.

My plan with the truck is just to cruise some on the highways, and I am not
Going to dragstrips with it, but I want the car to be fast, good acceleration, but
Nice cruisin speed. Some tell me that I need A TH 400 with a overdrive, but I just put a lot of money in this one to fix it, and this is also the original 400 that belongs to the engine..
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[YahamaR1]

So what kind of gearing do you think?
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[OrrieG]

Here is one of many tools on the internet that allow you to change gearing, transmission ratios, and tire sizes to see what your rpm at any speed will be. If you put in honest hp, weight, etc. numbers it will also calc an estimated 1/4 time and speed. http://vexer.com/automotive-tools/speed-rpm-calculator

FWIW my chevelle has a 350/TH350 (1:00 ratio in 3rd gear), 3.08 rearend, 215 x 15 tires and it runs between 2800 and 3200 in freeway traffic which is probably between 65 and 75 mph (speedo is broken).

Your goal of rapid acceleration and low rpm crusing are not possible with the 400 tranny, you need overdrive to effectively run lower trans or rearend gearing. That is why my wifes Honda (5 speed auto) is great between stop lights but will cruise at 1600 rpm at 75 mph.

[solidaxel]

A 3:55 or a 3:70 with 255X65 tiers I like them both, with the torque of a Big B. you could usa a higher, lower numerical gear and get better use of your engine.