Author Topic: 1984 c10 350-th350 to 454-th400 swap  (Read 3385 times)

Offline bones 84

  • New Users
  • Posts: 2
  • Newbie
1984 c10 350-th350 to 454-th400 swap
« on: October 02, 2014, 08:40:33 am »
Well i was wondering. i have an 84 c10 longbed that has a 350 with a flat cam and a 2 barrel and i have a buddy of mine who has a running 454 th400 combination in his rv he's wanting to sell me. 400 dollars buys the whole set up and i can hear it run. what all would be involved in swapping the assembly over? I was told i could use the 350 mounts but what about trans mount? Would it be just move it back and drill new holes? And will i need a new drive shaft? Obviously i would need a new exhast setup but what about wiring or gauges any different? I have no.idea what carb is on it atm but i have a 570 holley for it if i don't like it haha.

Offline Captkaos

  • OWNER and Administrator
  • Administrator
  • Senior Member
  • *****
  • Posts: 18461
    • http://www.73-87chevytrucks.com
Re: 1984 c10 350-th350 to 454-th400 swap
« Reply #1 on: October 09, 2014, 08:15:37 pm »
Trans crossmember will need to be moved, motor mounts can be used from the SBC on the BBC..  If you have a fan shroud, you will probably have issues with fan hitting...  The output shaft on the TH400 is different and you will need to modify the driveshaft for length.
As for wiring, nothing is different, some wires like coolant might need to be extended, but on the ones I have done, we just dropped it in and wired it up without changing.

Offline FlatBlack77

  • Junior Member
  • ***
  • Posts: 894
  • Cheap Fast Reliable - Pick 2
Re: 1984 c10 350-th350 to 454-th400 swap
« Reply #2 on: October 09, 2014, 10:48:23 pm »
you might get lucky scoring a driveshaft from a local salvage yard.

with things like that i usually just go and look because 90% of the time whoever answers your phone call aint gunna know for sure what they got in the yard
"When you are a hammer, everything looks like a nail"
'77 C/10 - 350/350 mild street motor