8.1L swap into my 7.4L K2500 Burb

[4Birdman]

Figure what the hell, can't hurt to research it. I did a lot of searching and couldn't find anything really definitive. My Burb is a 95 K2500 with the TBI 454. I am in the process of a complete teardown and rebuild and am investigating my engine options. Truck is getting an NV4500 swap.

One option is probably the smartest - doing a Vortec 454 with a FITech fuel injection system.

The other option - I can get a wrecked 2004 8.1L truck fairly cheap. I have no issues thinning the harness and doing a tune on it to have a stand alone ECM. I know it'll bolt up to the 454 mounts, just not sure on accessories and how they would work. Or if it is even worth the effort.

Any insight?

 

[Z71Hobbs]

Just my opinion..but I’d stick with the 7.4-more options available.

 

[someotherguy]

Since you're a TBI truck - either one will be just about as much work, providing you have a suitable donor - but you'll have a much harder time finding parts for the 8.1 down the road. Also the newer generation 8.1 donor truck will end up meaning much more work for you, harness-wise. A better donor would be a 2001-2002 GMT400 3500HD although it's possible that version of the 8.1 may be slightly lower HP thanks to tune and/or component choices for the heavy duty application.

Richard

 

[MIHELA]

This swap would be easier with a 96-99 and a 411 PCM swap. You would need to do a LOT of harness swapping and modification to go from 1995-1996 type wiring layout.

 

[BowtieBrody]

I'd just bore and stroke the 454 out to a 496, and then continue with the fuel injection kit and all that good stuff.

 

[Tom P]

I agree with BowtieBrody. If you are going to spend the time and money to go with a new injection system, might as well build the 454 the way you want it. I'd take a fresh 454 built my way over a used, stock, 8.1 any day. The 454's have more options for fun goodies like cams, pistons, heads and all that anyway.

 

[Biggershaft96]

Im an 8.1 fan, id like to see it done but youd probably be effort and perfomance ahead building your own 454 the way you want it. Rylar engineering is about the only place to find 8.1l performance parts and if something were to happen to the motor, theyre not the easiest to find replacements for. Also i dont remember what part it was but @thz71 had one that he had trouble finding parts for because people stopped making them. Just a few things to think about.

 

[skylark]

I noticed that the 454 guys are all chiming in as 454. Have you considered the 6.0?

 

[tanman_2006]

Unfortunately a 6.0L is a very real option. If you want more cubes then stroke it. As well all know the 6.0 is about as bullet proof as they come.

 

[Jay33089]

I did a 6.0 in my k2500. Pulls better than the 454 Burb I had! More pickup and mpgs too!