Not a lot of pre-73 4X4 LS swaps?

[robb13425]

I have a 71 K5 and the engine is getting a little tired. I am flirting with the idea of a 5.3 swap, but I am struggling to find information.

From what I've found, crossmember and mounts seem to be the biggest mecanical hurdle. There are multiple options for 73-87-(91) trucks' crossmembers, but not too much for 68-71.

 

[bigblock72]

You can use the stock crossmember with the holley style motor mount adapters.

You will have to move the transmission forward 1-2 inches for firewall clearance.

Truck style manifolds won't clear the frame without cutting.

What transmission are you going to use?

What type of fuel delivery and electronic system are you going to use?

If you can do the majority of the work and can get an engine for a reasonable price then it may be more cost effective than building a new 350 and putting fuel injection on it. Let me know if this something you are going to pursue and I can get more specifics for you.

 

[metalneverdies]

You can use the stock crossmember with the holley style motor mount adapters.

You will have to move the transmission forward 1-2 inches for firewall clearance.

Truck style manifolds won't clear the frame without cutting.

What transmission are you going to use?

What type of fuel delivery and electronic system are you going to use?

If you can do the majority of the work and can get an engine for a reasonable price then it may be more cost effective than building a new 350 and putting fuel injection on it. Let me know if this something you are going to pursue and I can get more specifics for you.

Even with engine mount adapters? You can't keep the engine in stock location?

I had read some where dougthroley had made some swap headers. I not positive they work on first gen k5's but its worth checking on.

 

[bigblock72]

Even with engine mount adapters? You can't keep the engine in stock location?

I had read some where dougthroley had made some swap headers. I not positive they work on first gen k5's but its worth checking on.

I tried leaving the transmission in the stock location on mine and the valve covers hit the firewall 2 inches before the bellhousing lined up.

I have heard of people modifying 4th gen camaro headers but haven't tried it myself. I gave up on trying to find something that would work and made my own.

 

[Mark1968]

There are quite a few swaps into the earlier trucks on that other message board.

 

[el curioso]

You can go to 67-72chevytruck.com Alot of info there

 

[Mark1968]

That's the one I was making reference to. Somewhere over there is a list of build threads by year but I can't find it atm. Edit: Right here http://67-72chevytrucks.com/vboard/showthread.php?t=457939