I have a 93 k1500 w/4.3 v6, i also have a carb 350 out of my 74 c10 i want to install in place of the v6. question is has anybody done this swap before and do i have to take the computer out of the system. also the fuel pump, i know i have to put the mech one on the block, but do i need to replace the fuel sending unit for a non inj unit
any help or info will help out....thanks

rock on!!!!!!  

this is a fairly common swap, however i've never done it. i would think you will have to swap sending units as inj pressure would be too high or install an inline regulator. the computer will be scrap for the motor but you may need to retain it for the tranny. if this is gonna be a daily driver you will also have emissions issues to address. sorry i can't help more, good luck!  

Personally, I would not do this swap. 74 350's were kinda pigs with low compression and mild cams and retarded spark curve timing. You will see a BIG increase in fuel usage. Furthermore, your 93 tranny is a 4l60E which is fully electronically controlled and it will not work right with no engine inputs from carbed motor. If you want to use the engine you need to find a 700R4 to replace tranny because it does not need a computer. I would suggest that is you 4.3 runs okay you simply regear the axle in it. If it has a lift and some tires on it some 4.56 or 4.88 gears will really wake it up and run better than 350 carbed motor overall and use less full too. Also be advised that some 4.3 application then used a 4L30 with is a LD version of a 4L60 which is okay with 4.3 but it will not like a 350.  

your not suggesting that a 4.3 will out power a 350?  

chopperfreak2k1:
your not suggesting that a 4.3 will out power a 350?

That year 350 was rated at about 160 HP as a 4bbl and 145 as a 2 bbl. Power wise they were the worst of the smog 350's. (73 and 74 both and I was driving for some time when they were new!) What I am saying here is that if he has a lift and tires that his truck likely has  3.42 axles and that plus lift and tires equals slug. If he were to regear it with 4.56 or 4.88's or even deeper (depending on tire size) it would out perform old 74 350 and stock gearing combo in that truck. Many do lifts and big tires and when it is a slug they blame engine rather than the fact they should have changed the axle gear ratios with the lift too.  

i agree with that 100%  

i see what your saying but i didnt mention my p up has a 5 spd w/ granny and 373 gears, so i dont have to worry about auto trans......so lets add that to the equation and see what you think!!!
thanks  

oh...also my p-up is what chevy called the W/T 1500 4x4
so its very plain jane  

use the 4.3 oil presure sender stuff on the 350 that will run the stock electric fuel pump, you don't need to use a mechanical on this swap, plug it off. the extra line can be plugged,
get rid of the 882 cast heads and put on 68-72cc it'll have more power even with the stock cam, way more

I have done this exact swap in a 92 k2500 light duty it is hassle free, and the front pulley brackets from the 4.3 bolt on the old 350 so you can keep all the accesories,fan, alt, ac. power steering, using the serp. belt, even the stock exhaust cross over will work, I used a set of smoged tube headers though and hooked up the smog/air pump, hey, I still have those in the shop, I changed to hookers and went dual 2 1/2"  

thanks, mud....thats good to know i can use my accs. and pump.
i planned on using all summit internals, .030 over on the 350, headers, everything from summit just to how well the stuff holds up perf. wise and reliability wise.i had a set of summit headers on my 74 c10 350 and had good power and no problems so what do ya think...theres no lift as of yet but plans are for a 6" lift and 34" super swamper LTB's, i think my 373s will be ok too.  

You are WAY off on being okay with 3.73 and 34's even with a 350. (kinda like 3.23 with stock tires, stinks off road) Also unless someone has done a tranny swap, that truck came with a NV3500 which does not have a granny as first gear is only 4.02. I would not put a warm 350 in front of it. Then there is the drive axles getting into gray area. If you installed some say 4.88 with 34's that would give you about 2300 RPM in 5th at 65 MPH which would be okay but you would not want it any taller because 5th would not work/pull well. Quite honestly you would likely be very pleased and surprised with its performance with the 4.3 and 34's with 4.88 or 5.13 gears. SOme look at OD trannies as 3 or 4 speed boxes plus one gear you use some of the time. I look at it as being able to use all the gears fully all the time (not just when wind and grade is right) and gear my trucks accordingly.  

yeah great, I gotta go with snoman on the gear though, I'm sure you've considered it some.  

my 4.3 was still a slug with the 5sp 35's and 4:56's, part of the reason for the 350 that got stuck in it. the carbed 350 also got better mileage than the 4.3 did. I do kinda wish I put in 4:88's. that long past, now the truck went to alaska and i sold it.
I ran a pair of 048 casting heads on a 73 monte carlo block stock pistons, summit 260 cam. great power and torque.  

well it sounds ALOT cheaper to go w/regearing the axles...(it will keep the wife on the quite end of complaining too much too!! lol! )honestly the engine may be a slug but i have NO problems w/it. not even a lifter rattle/no internal noises either.put quite a few new parts on it to make it run good too....so i'll price out some gears for frt/rr and a locker for the rear too...
thanks snow and mud... any suggestions on brands for gears?  

thanks to chopper too