I recently bought a 97 3500 express van nice and cheap.

The high mileage 5.7 is disappointingly tired.

Rather than dump money into that I'm thinking LM7 swap with turbo.

We live at ~7000ft above sea level, and have to go over a 9,000ft pass quite often.

Not looking for huge numbers or a great deal of speed just some mild reliable HP.

 

Go for it.

Just a 5.3 alone will make it feel worlds better than a clapped out 5.7 vortec.

 

Yep. I may be getting ahead of myself here. I think I have found a 5.3 with harness etc for reasonable money.

Still need to do the work of the swap and the 5.3 may be enough.

Even so I can't help but think I'd be missing out by feeding it thin high elevation air. So I asked a bunch of newbie questions over in the forced induction section:

https://www.performancetrucks.net/fo...liable-538333/

 

Honestly I think it would be better to put a tvs1900 on that 5.3 once its swapped in. This way you keep it reliable with plenty of power and no spool time, no need to deal with complicated exhaust/intercooler routing in an already cramped engine bay either.