Cant find it in a search so Ill ask here. Isnt there a way to determine which injectors are in a tbi by the color of the connector pins. I scored a tbi setup which I beleive to have come off a 90's full size blazer but I need to verify.

 

There sure is. Check this out.

 

I see from the chart that 4.3 injectors flow 45 lbs as opposed to the 5.0 that flow 40 lbs. Do you think there would be any advantage to the 45's on a mostly stock 305. (open element, cat back, timing advanced). Or would you need custom chip work to see any gains?

 

Your stock injectors are fine until you have a nice set of heads and a decent cam. Going bigger at this point will only cause problems.

 

Are you sure the stock 5.0 injectors are 40lbs at 13psi? Because I have a hard time believing that the 4.3L (which made less power) has larger injectors. I was always under the impression that the stock injectors were 50's. In fact I refuse to believe they're 40's, that's just impossible (please prove me wrong ).
Just increase the fuel pressure. New flow rate = old flow rate * sqrt(new pressure/old pressure).
So to get more fuel into the engine without tuning your eprom you can just increase the fuel pressure. The stock regulator can EASILY be turned into an adjustable. It's a tech article! Also, don't, whatever you do, increase the pressure without watching the fuel pressure under high load (high gear high speed acceleration). The stock fuel pumps are junk and dead head very easily. Good time to replace the fuel pump if it's original and over 150k miles. Walbro 190lph is perfect and the kit can be had for $90.

 

Good eye JP. I never really studied the chart that closely to catch the error in it. They just have the 5.0 and 4.3 #'s swapped. The 5.0 should be 45 and the 4.3 should be 40.

 

While were on it, I would like to suggest that even with a cam and heads in my 350, the 90's in my opinion are WAY too big. The idea that we need all the fuel we can get because of going static or something to that effect, I'm not buying.

I'm not even sure why GM put the 65's in the cop car. I really don't see a need for it with that mild motor.

 

I think they used those because the engine was always under extreem load with that boat of a car that it was in as well as the fact that a little extra fuel can keep temps down a bit.

 

Has that motor been to redline at WOT yet?

RBob.

 

Trust me Gunny, TBI's have a problem with high RPM fuel delivery.

 

define "high RPM."