98 k2500 nv4500 350 to 454 swap opinions

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jaxcob

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Hey everyone, been running the 5.7 in my 98 k2500 with the nv4500 and 4.10 gears for a while now. Upgraded to the mpfi spider from the poppet style among just random things here and there. Graduated college, got a job over in Southern Iowa and finally started the house buying process so a lot of 'fun' there. Lost most of my ability to work on projects for the time being but was also wrapping them up so itching for something new. Got a line on a 97 454 long block with ecu and some accessories for $200. Now i know my 350, with my driving, gets about 14-16 at best and there's some small things i could do to maximize that but as the house is a couple blocks from work, the big block doesn't worry me on mileage. Guess the question is in your opinion, is the 454 worth swapping to?
I'd be buying the engine and all with the idea to do this in a small garage over a few months here in the late summer and fall.
Applications would be for some towing but mostly having fun and gravel/dirt road. Plan is to have this truck and build for fun/working and get another truck in the future to fit the whole family.
EDIT: More info on the bb. Pulled in good running condition supposedly, has the egr tube and wiring harness. Guy wanted his built engine going in this new setup instead of the bb.
 

Schurkey

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Gonna be interesting if that $200 engine doesn't have all the accessory drive system included.

Bigger radiator, stiffer front springs, exhaust mods to match the manifolds or headers, too.

I really like my 7.4L K2500.
 

L31MaxExpress

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Gonna be interesting if that $200 engine doesn't have all the accessory drive system included.

Bigger radiator, stiffer front springs, exhaust mods to match the manifolds or headers, too.

I really like my 7.4L K2500.
Kwik Performance sells an adapter bracket set to bolt the small block brackets right on. Used them when I put a 396 in place of a 350 in a 94 G30 van.
 

jaxcob

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sorry for the lack of info, with closing on the new house and now the transmission issues I dropped the fun projects for the time being
 

letitsnow

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If you aren't going to be pulling a heavy trailer often and for lots of miles, I'd stick with the 5.7.

You don't have much of a commute now, but it is a good idea to stay flexible as life sometimes changes. The 5.7 will still git r done, and get ok mpg empty.
 

DTrain

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I know you said you dropped the project...but I did the swap. Cost more than $200, a lot more. And when you think you know what it may cost, ad a whole bunch more. But man was it worth it. The 350 is awesome, but personally I didn't realize what I was missing until I had what was missing...BIG BLOCK POWER!! I have a NV4500 too, really makes for a fun truck to drive. Hope you don't totally lose the bug and get back to a project again soon. I'm about to embark on another 350 to 454 swap here soon. What's MPG anyways?!
 
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