I'm currently running 24 lb Bosch D3 injectors on a 350 sbc. I've got ProComp heads (yes I know they're cheap *** heads), Wieand Stealth Ram intake with stock TPI throttle body ('87), and a Comp Cam with the specs in the pic below. My question is, is 24 lbs a good size for a 350? I'm running a FAST EZ EFI 2.0 multiport retrofit system for multiport. I can give more details if needed.

 

That's pretty much in the ballpark. Maybe a shade on the small side but that would depend on the RPMs you expect to be running. Which with that cam, I think they'll be OK. May come close to going 100% at the outer RPM limit it will run, like 6500 or something, but should be OK. Especially if you can dial in acoupla more psi of FP.

 

I was able to kick the FP up to 50 psi but I haven't driven it at that yet. I found a burned up plug wire that was touching a header. So I gotta fix that first. Smh. I've seen some posts of guys suggesting 30 lb injectors on 350s but I don't know what kind of setup they're running. I got the injectors from southbay and they claim they flow 27 lbs @ 43.5 psi.

 

You "can" run any arbitrarily large injectors on any arbitrarily small motor. Doesn't mean it's "ideal". Let alone A Good Idea.

If the injectors are too small it will obviously go lean at max power & RPM. Very bad.

If the injectors are too large it will go rich at idle and similar conditions. The mechanical limitations of injector behavior determine how short the pulse can possibly be. If that's too much for idling, then ... Very bad.

Either direction of error is Very Bad. Fortunately you have a tool that can help overcome this, in the form of fuel pressure.

Personally I'd rather have injectors that are toward the small side, without being too small, and high FP, since that way, the fuel is going to come out in a forceful spray, rather than dribbling like a leaky faucet.

I think 24s are a good starting spot for what you've got, if they're Bosch ones. Try em and see what they do. If they go lean at the extreme of your operating conditions, get some that are slightly larger. Maybe 26s from a stock LS1 or something around in there. Not a good idea to go to, say, 36s or some such.

 

After cranking the FP up to 50 it was driving very well. Very smooth acceleration. No bogging. Doesn't go lean. But then I ran into another plug wire arcing issue. Burned one right down to the core and now I found another one. I'm gonna have to buy a new set of wires, some good wire looms, and some heat sleeves for the wires. I should have just done that from the get go. Thanks for all your input! You've helped me several times in the past bc I remember your handle.