AVS2 carb tuning. Anyone with experience out there?

furrystump said

I have been playing with a 800 avs for a while and am really pushing it beyond its comfort zone. Not sure what info will be helpful, most of this won’t help you, but some interesting things I have noticed. I was surprised that the 800 AVS could support 600 hp being it is really NOT a race carburetor.

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I had one on my 360 and it would go lean at the hit on the start line so I did a bit of investigative work to see why. With the floats set to their correct heights the fuel level was just too low in my view to fill and keep the pump shot well filled. So I cut up an AFB top at the front and adjusted the float settings to see where it actually should sit with various heights on level ground. They didn't match up so I ran the 800 AVS as high as possible to get it where I needed it but if you go through the Carter literature you'll find that they recommend lower float levels with a bigger needle and seats so that would have been the better way to go. When you consider the original Carters and how the feed to the pump shot well has a one way check valve at the bottom of the bowl feeding into the well you understand how it works. Later carbs do not have this feature so it needs to be higher to get into the slot. Add to that the inertia of forward movement and the fuel is being pushed to the rear of the carb it makes it harder to get there as well. So check the "actual" fuel height. Just something else to look for when tuning your carb.