Late model I-6

Just wondering if anyone has looked at the possibility of installing one of the late model I-6's from something like a Chevy Trailblazer in a 1st gen?

That's what Suicide King is doing.

My wife's car is a Trailblazer and I have a friend that built a 53 Chevy sedan delivery with a Trailblazer six drivetrain........
Those engines are not small and are not very easily swappable.... Nothing about them naturally adapts or bolts up to anything...There are lots of interferences on the bottom side when trying to adapt one to a car that probably wouldnt be problematic in one of our vans.
With so many cool BBC and SBC combinations that basically bolt right in and run circles around a Trailblazer, I don't think the payoff would be worth the pain.... Also, it might interest you to know that a Trailblazer gets around 13 city and 19 highway, so our old 230/250's with a 1bbl carb are actually thriftier!

Thanks for the input Samsvan and AzDon. After looking at Suicide King is doing I decided that would be way above my skills. Those engines look huge compared to the 250.

Before I switched to the 350, I was going to put in a 4.3 V6. The motor mounts and bolt pattern for the tranny is the same as any SBC.

the local van club I belong to has 2 early vans with the 4.3 in them
both also have 700r4s behind them and both of them get 20mpg hwy
but they are both tbi fuel injected.

If you going to go through all the effort of doing a swap to late model engine check out the ls series from gm 4.8 5.3 6.0. Motors are in every junk yard because they never die, and usually cheap.The 4.8 is rated @ 275hp and would move a van just fine. The wiring harness is pretty simple and can be made stand alone in an afternoon. I haven't got to drive my 5.3 powered van yet for milage . I have a 4.8 in a 1/2 ton full size 4wd truck and it gets 19-20 around town. My dad had a two of the same pickups , one with a 4.3 v6 and the other with a 4.8 v8 and the 4.8 got better milage