8.1 LS swap?
 

Posting this just to see if anyone has done anything along these lines, or has any thoughts. Found a 8.1 LS motor on Craigslist, thinking about swapping into '87 Silverado 3/4 ton. Truck has factory TB 350 and Muncie 4 spd. Would like to keep the Muncie if possible. Any thoughts or opinions appreciated!

Re: 8.1 LS swap?
 

The 8.1 is not an LS based engine, it is an L18 based on the original big block Chevrolet. There are a lot of them out there in commercial applications and they also share ECM similarities with the LS engines but... there is not much aftermarket for them. The heads/intake/firing order are all different from the Mark IV traditional big blocks and the relatively short run left them out of a lot, especially since the LS based engines became so prevalent.

If you want a stock swap with good manners and killer torque it's a great option, just know what you get it what you'll have, there won't be a lot of easy modding with it.

Re: 8.1 LS swap?
 

Oh yeah, it's been done. And fortunately the fella who did it the best is a prolific poster here and very generous with sharing information. Search for user Dirty Larry here on this board. He has written extensively about putting an 8.1L in both his 78 shortbox expedition truck and more recently into his 89 suburban.

Over on the CK5 board he even started a specific "L18 8.1L swap resource thread"

Here is his Polar Bear Suburban thread here on this board. The 8.1L specific stuff is towards the end.