1970 k10 Shortbox - 402 BBC Swap

[gmc 2500 4x4]

i have a '71 402 that was pulled from a chevy truck. are these 5 quart w/ filter? i came across a 6 quart on evilbay and they say its for 2/4wd with correct clearances, 396,402,454

[no1udknow]

to save a little space on the front end, have you considered electric fan/water pump?

[Gawdly]

Originally Posted by no1udknow

to save a little space on the front end, have you considered electric fan/water pump?

Space shouldn't be an issue... The angle of the engine with the aftermarket motor mounts may be an issue. It may not let me use the factory shroud. My fall back will be an electric fan setup on the stock 4 core radiator.

[Gawdly]

Anybody know what this extra connection is on my new 4 core radiator from brothers right below the trans cooler connection? My other radiator doesn't have it. What goes here? Or just plug it? Easy way to plug?



Core support and radiator are in. Engine is actually sitting lower than I expected. Only 1/8 to 1/4" gap between fan and shroud at the bottom. Works, but just barely. Almost perfect position front to back. Fluids are in. Just need to mount the starter, route a fuel line to carb, reinstall the gauges and do some minor rewiring then it'll be ready to fire.

I swapped to an auto pedal assembly. Since then I haven't been able to push my brake pedal in, seems stuck, can push it in at all. I can tell from the engine bay side that the rod to the brake booster is fully extended out. Everything is hooked up right. Thoughts?

[gmc 2500 4x4]

thats for the heater core line.

[Gawdly]

Originally Posted by gmc 2500 4x4

thats for the heater core line.

Hmm... So instead of the heater returning to the intake manifold, it should return to here? So water pump to heater, then heater to here?

[Gawdly]

Found it, intake manifold to heater core inlet. Heater core outlet to radiator. Bib on water pump not used.

[gmc 2500 4x4]

old post, wondering on headers fitting a 3/4ton 4x4 with a 402 also. best headers?

[402Bowtie]

Resurrecting an old post...hoping to do the same configuration: 402 BBC, 700R4, and NP205.

Three questions I have:
1) Has the OP or anyone else experienced issues running the 700R4 behind the 402...or is the key to have the 700R4 built to handle a 402? I'm expecting only some occasional towing and in-town driving.
2) What headers are people using in a similar setup to what the OP describes?
3) Anyone with this setup have any other tips?

[Mryan]

Cool truck! Lots of good information, Thank you guys! I have a 71 short 4x4 with a 454 4speed that I bought a year ago and am slowly getting through the mechanicals.

[Jack15T]

Hi Myron, I also have a 1971 K20 with a 454. Mines an auto with a long box. I bought it about a year ago and the 454 engine is sitting on small block mounts and crossmember. The engine is hitting the firewall and the exhaust is hitting the frame rail on the passenger side. Is your engine sitting on a small block set up or did you find a clean solution to the fit issue? I was wondering if the Big Block crossmember and perches from a 1971 C10 would work in a 71 K20? I have a new 454HO from Chevy ready to go in if I can work out the mounting issue. Thanks, Jack

[Jack15T]

My apologies for miss spelling your name. Jack

[72Cheyenne454]

It's been a long time... but I remember using a passenger car single step BBC oil pan when I installed a 454 in my 72 K20. The passenger car pan cleared the factory engine cross member with no issue. I left the engine in the original spot and had to modify the firewall for valve cover clearance.

I'm not sure how the early passenger car and factory 67-72 BB truck oil pans differ.

Here's a few pics of my truck with the BBC in it and also a better internet pic of the passenger car oil pan I'm referring to.

Maybe this info will help those considering a BBC swap in the future.

[Jack15T]

Thanks for the info and the pictures. Beautiful job!

[Mryan]

My truck was done by the PO, here is what I've seen. It looks like they moved the crossmember forward by an inch or two and has some welding done to it, the oil pan is dented...is that because it needed to be? additionally the transmission etc... has all been shifted forward. I am preparing to remove this engine (to reseal) and have purchased a crossmember from DIY 4x4 and a new oil pan. I hope to be able to clean things up soon. Let me know if you have a question you think I could help with or need a picture for clarification. Good luck!


Mike

[Jack15T]

Thanks for the info Mike.