My 54 Chevy has a peppy sbc in it. bored .030 over, moderate cam (238 @ .050), big valve ported/polished heads, headers. 10.5:1 compression. Its backed up by a 350th tranny with B&M 2400 stall Holeshot converter. The rear is a 9 inch ford unit with 4:10 gears. This car was bought for a daily driver and I'd like to put a overdrive tranny like the 700r4 or a 5 speed in it to make it a little more highway friendly while still keeping that bottom end grunt the 4:10s deliver. I was thinking a lower stall converter if I go with the automatic. I was wondering what would be the better swap? What mods are going to be required on both? I hear the 700r4 is a easy swap. I love driving a standard shift too though. Whats the cost difference between the two? Pros cons? Do I have to modify the driveshaft length for either? crossmember? I never have done anything like this before so your help is great. thanks alot
mid length th350 vs a 700r4 are nearly the same length. within an 1/8 of an inch. you can usually use the same drive shaft. I havent done it to my 51' , but I hope someone posts a little info on it.
The 5-speed would be the better swap. (IMHO) You still get to have 3 pedals, which according to someone's signature, makes a real hot rod, and I agree. If you do a lot of town driving, it could get annoying after a while, so you might opt for the 700, but if it were mine, I'd put in the stick.
I have had both, but ask your self what you want to do...do you like to shift? do you live in or around alot of lights? is this a cruiser? a daily driver? You can still manually shift an auto if you like. Both options can cost you a little or alot depending on how much you want to spend. The automatic is probibly the cheapest and easiest on your car...and easiest to swap as well...slamin gears breaks stuff....always!!! But its fun. if you go stick you gotta get a pedal assembly and set that up. For both swaps you gotta change your trans mount and have your drive shaft cutt. Honestly the cheapest route would to be to change your gears to a 3.55. It'll give you the alot more up top...if money is no object....6spd!
I put the t5 in my 54, and have 4.10s in the rear. I have a built 235, but it still doesnt seem to go fast enough on the freeway, even with the 5th gear. I can hang around 65-70, but I like the 80mph fast lanes. I am thinking of puting in a lower set. The t5 is only designed to handle 300hp max, and there are many different 5th gear ratios. If memory serves correct, I have a .68 5th, which is the lowest I can find. If you do go with the t5, make sure you find the correct bell housing. The angle that the clutch fork is different than later bell housings. I installed the later one, without knowing a difference. Now the geometry of the pedal linkage to teh arm is way way wrong. I thought I could solve this by making a linkage. Even with 3/4 round stock it is bending the linkage, and I have made two different ones trying to correct the problem. I say go with the manual, theres nothin like ripping through gears. Just do the home work. Here is link to the inliners site that will go into more detail about the bellhousings. http://www.inliners.org/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=2;t=000680
I picked up a used Blazer this week that has a 350/350 in it (plan on poaching the drivetrain for my '54) and the automatic has been a nice change. I'm usually a 3 pedal man myself. But it has a Hurst Pro-Matic II shifter that lets me shift whenever I feel the need!
I'm not sure on the horsepower mine is putting out. This is my first sbc actually. Its a .030 over 350. moderate cam (238 @ .050), big valve ported/polished heads, headers. 10.5:1 compression. Has a low rise edelbrock single plane intake and a holley 4 barrel. Thats all I know right now. I'd be happy to cruise 70mph thats good enough for me.
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