Transmission swaps
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Transmission swaps
So I have a 1966 f100 and I have the granny geared 4 speed that I believe is a c4? I was just wondering what are some options I would have putting in maybe a higher geared 5 speed ... let me know thanks !
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4 speeds: Borg-Warner T-18 - Reverse is up - towards the dash // New Process 435 = Reverse is down - towards the seat.
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I wanted to swap my NP435 for a 5 speed until I saw how much work and money it takes. You’ll never make back the money saved in gas mileage. Swapped to taller rear gears but other than that I just cruise it as 60 on the freeway like they did in the good ol days
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I priced out a trans swap to a five speed and like Christmas said, right around $4500. I still may go that route next year, but in mean time I swapped gears from the 4:10 to 3:54 and it’s a pleasure to drive.
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More Turbo
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I have a 95 ZF S5-42 behind my 300. It was a combo that dad put together when he was sourcing parts for the truck. It has a granny first gear, but will run 75-80 down the highway by the time you hit 5th. I'm not sure what gears are in the rear end.
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I must have the NP then because my reverse is down ... I have a 390 with a 1973 3/4 rear end ... I wouldn’t be interested in swapping but going about 55 60 has it running at pretty high rpm and one more gear would be nice
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[QUOTE=Vandy23;19239401]I priced out a trans swap to a five speed and like Christmas said, right around $4500. I still may go that route next year, but in mean time I swapped gears from the 4:10 to 3:54 and it’s a pleasure to drive.[/QUOTE/)
I have a fairly hot 352 in my 65 F100. Going through a 3.03, three on the tree with 3.50-1 out back, spinning 31x10.5x15 tires. I have a 325-1 pumpkin I could swap in, and another that I think is like 3.0-1. what do you think about the 325, still enough grunt to get it going, but drop the rpm significantly on the freeway? Would 3.0-1 be okay? I know the 398-1 is out the window!
I commute in SoCal and to not be an obstacle I'm running around 3300 rpm on the highway.
I have a fairly hot 352 in my 65 F100. Going through a 3.03, three on the tree with 3.50-1 out back, spinning 31x10.5x15 tires. I have a 325-1 pumpkin I could swap in, and another that I think is like 3.0-1. what do you think about the 325, still enough grunt to get it going, but drop the rpm significantly on the freeway? Would 3.0-1 be okay? I know the 398-1 is out the window!
I commute in SoCal and to not be an obstacle I'm running around 3300 rpm on the highway.
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You might save gas, but you won't save money.
Since you have a 3/4 axle, I assume a Dana 60, a gear change would be less money than the transmission.
Or the old taller tires trick.
*There is a 4 speed OD from the '70s-'80s. Geared like a 3 speed, big gap 2nd to 3rd and not a heavy duty transmission. Some here have run the iron cased version behind an FE.
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.......................
I have a fairly hot 352 in my 65 F100. Going through a 3.03, three on the tree with 3.50-1 out back, spinning 31x10.5x15 tires. I have a 325-1 pumpkin I could swap in, and another that I think is like 3.0-1. what do you think about the 325, still enough grunt to get it going, but drop the rpm significantly on the freeway? Would 3.0-1 be okay? I know the 398-1 is out the window!
I commute in SoCal and to not be an obstacle I'm running around 3300 rpm on the highway.
I have a fairly hot 352 in my 65 F100. Going through a 3.03, three on the tree with 3.50-1 out back, spinning 31x10.5x15 tires. I have a 325-1 pumpkin I could swap in, and another that I think is like 3.0-1. what do you think about the 325, still enough grunt to get it going, but drop the rpm significantly on the freeway? Would 3.0-1 be okay? I know the 398-1 is out the window!
I commute in SoCal and to not be an obstacle I'm running around 3300 rpm on the highway.
Change to 3.25 you would run 91 MPH at 3300. (70 = 2548, or roughly 27mph/1000rpm)
Change to 3.0, 98 MPH at 3300. (70 = 2352, or roughly 30mph/1000rpm)
So you are either driving too fast, or your tach or speedo is wrong.
If you have a good clutch and a deft foot, you can run the 3.0s with ease.
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