this doesnt make sense

[1972BlueC20]

Ok so I been trying to resolve an off idle / off cruise bog or hesitation issue for weeks now.

I've covered all the bases before digging into the carb. You can read all that I've done and checked before delving into my carb HERE :

http://67-72chevytrucks.com/vboard/s...d.php?t=661895

I'm dealing with a Holley street avenger 670

So I was pretty certain I needed to increase my squirter size up 3-5 sizes. I read online that my carb should've had a size .031 squirter in it from the factory. So I ordered a tube style .035 and installed it. I now have horrible throttle response. So I looked closely at the squirter that I had just pulled out and it was marked 42!!!

How on earth did my carb have a .042 squirted in it from the factory??

So now I'm confused, do I go up to .045 + ?

It doesn't seem right that a stock GM crate engine (part # 19210008) would need such a big squirter to run right.

What do you guys think?

[nzc10]

Hey there i was having a similar problem with my 350 even with new carb, fuel pump and manifold stalling at lights and hesitate a cheap way to see if you are starving of fuel is fit a clear in line plastic fuel filter and when it stalls check for gas in it mine was emptying out so i knew i had a fuel supply issue checked all my fuel lines found the rubber fuel hose coming out of the cab to the chassis rail was perished it and kinked also was above the muffler which did not help so replaced the fuel hose with some heat insulation around it and that fixed my problem. I know you have said you have replaced the fuel hose but that piece can be easy to miss hope this helps. Good luck!

[REEDS 72]

If your vacuum advance hose is connected to the ported line coming out of the carburetor plug that one and change it to the manifold one that's the one next to ware the pcv plugs in in front and at the bace of the carb. Try that and see how it runs if you have allredy done this then ok I did not read the whole thread hope this helps.

[69chevy lwb]

I had the same issue my float bowls were to low when the engine was running. But with an electric fuel pump they always looked right when I checked. Set them while running and then set the accelerator pump up again. Mine was adjusted to try and compensate for the lack of fuel so I had to fix that.

[1972BlueC20]

Thanks guys for the ideas, but I've replaced all the fuel line on the truck and tried with and without vacuum advance as well as trying ported and manifold vacuum.

[1972BlueC20]

That's an idea to try, thanks!!

Originally Posted by 69chevy lwb

I had the same issue my float bowls were to low when the engine was running. But with an electric fuel pump they always looked right when I checked. Set them while running and then set the accelerator pump up again. Mine was adjusted to try and compensate for the lack of fuel so I had to fix that.

[1972BlueC20]

Anybody else heard of a stock Holley 670 street avenger coming with a size .042 squirter ?