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New project 94 C3500 350

It's nuts looking for the parts. The 454 sending unit is easily 100 less than the 350 tbi and 350 vortec sending units. Not sure what the difference is or if it matters what sending I buy vs the pump I use.
 
Not sure what difference there is if any in the senders. The 454 pump and sender should drop in no problems. I believe the tpi pump requires modifying the upper pump mount to use it, and really unless you're turning it up beyond stock, it isn't needed.
 
The vortec 350 and and eagle 383 kit I found on Craigslist over the weekend for $200 say I should put in a bigger pump in preparation for me to try something stupid haha
 
I'll go with the 454 sending unit and vortec pump with new strainer.

If plugs are different on the truck end that doesn't matter seeing how it's just rigged to work with random splices and will take a pretty serious soldering job anyways while I'm in there.
 
I think you're trying to throw too much fuel at it myself. If you're staying stock, that vortec pump is meant to push around 28 gph at 62 psi, that's alot of fuel for the tbi regulator to bypass to keep pressure down under 13. You only need a pump that can push 22 gph at 12 psi for that engine. That's why I reccomended the EP377, but I wouldn't dare go bigger than the TPI pump as even that pump can cause higher pressure at idle. I would also HIGHLY reccomend going with a 3 wire O2 sensor. They put them in the trucks with the 4l60E for 94 & 95, and it really helped driveability at slow speeds.
 
The 02 sensors are next on my list but first it should run half way smooth before I even worry about that.

The other forum is preaching the vortec pump hard saying the TBI regulator can handle it and to adjust my psi to 18 psi when I rebuild my tbi with the "ultimate tbi mods". The local dealer ship (gasser gear head as head mechanic) said he puts the vortec pump in customer trucks if he knows they push it hard.
 
If theres a need for it, yes. I don't see it, and was just helping somebody earlier today because he got talked into all that and now his truck runs like crap when it's cold and overfueling.
 
My truck will be plenty heavy once it gets its new bed. I guess if it runs rough I can always throw a regulator on pre TB until I get the mods to use the fuel.

Honestly it couldn't run worse than it does now.
 
So changing the sending unit I have found there is a hand bent copper line that it T'd into the return at the top of the sending unit and goes all the way up to the charcoal canister.
 

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I left it off and connected the soft 1/4" vent line back to the hard line.

Truck runs pretty good, still sluggish in 5th over 60 but I got up to 85 in 4th then shifted and it kept pulling to near 100 before I let out. No more bucking, cutting out, or hard starts (just shut it off and restarted 3 times so far). Sounds good idles smooth.

The "Basket Case" is coming around. Not to swap a better bed on and set it up as the service truck.

Side not the LML is likely sold.
 
Btw, the sending unit was 1" too tall but some creative use of a tubing bender got it to fit.

The rubber line on the pump was split. I really think that is the source of my headache
 
The gauges don't light up when I flip the lights on and the radio light goes out. The gauges all still work though. Tail lights still work and all fuses are still good.

Any ideas? I'm thinking light switch is crapping out, would that cause this?
 
Never had that one fail but makes sense. There are no cab lights inside so I can't turn it up and see.

Good thing the truck has a certain feel at 60ish.
 
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