Avanti R/2 AFB metering rods and jets

[jtjim]

My 64 Avanti lived all of its life in Denver Colorado. Now it is in Ohio. The owner in Denver told me that he was never happy with the Carburation. I would like to start over from stock origional if possible. I have read all the posts I could find relating to Metering rods and jets, etc. Here is what I have: Model 3588s carb-- Metering rod stamped with number 16-22, measures .074" X .068". Primary jets stamped with Number 120-162, measures .101". The step up springs have been cut off-- Currently what I have is .017" wire diameter X 1.125" long. I got some information from a post that said I should have rods measuring .076" X.049" amd jets measuring .101"----first step lean .077" X .0515" with same jets. Actually it runs very good except for the hesitation off of Idle. I have double checked Timing, vacuum, and everything I can think of. I must feather the gas pedal a little to get a few RPMS before it comes on. Is there any expertise out there. I have a strip kit with various rods and jets and could do the calculations to see what I might have to use, but would like some more input. Thanks, Jim

[JDP]

My 64 Avanti lived all of its life in Denver Colorado. Now it is in Ohio. The owner in Denver told me that he was never happy with the Carburation. I would like to start over from stock origional if possible. I have read all the posts I could find relating to Metering rods and jets, etc. Here is what I have: Model 3588s carb-- Metering rod stamped with number 16-22, measures .074" X .068". Primary jets stamped with Number 120-162, measures .101". The step up springs have been cut off-- Currently what I have is .017" wire diameter X 1.125" long. I got some information from a post that said I should have rods measuring .076" X.049" amd jets measuring .101"----first step lean .077" X .0515" with same jets. Actually it runs very good except for the hesitation off of Idle. I have double checked Timing, vacuum, and everything I can think of. I must feather the gas pedal a little to get a few RPMS before it comes on. Is there any expertise out there. I have a strip kit with various rods and jets and could do the calculations to see what I might have to use, but would like some more input. Thanks, Jim

It could be the metering rod springs, they have a big effect.

[jtjim]

I am suspicious of the springs. Does someone know what springs are supposed to be used. There are a couple of different springs in the strip kit I could try. I read the plugs and they look good. If anything, slightly lean. I calculated the area for the rod/jet combination. The difference on the small diameter is substantial---.0036" vs .0061". That is substantially leaner than than stock.

[bige]

Try something close to the recommended rod out of your Tuning kit and use a spring that's rated for the highest vacuum...the kit will tell you what color spring corresponds to what vacuum rating. The one that was in there is definitely lean on the power side and if the spring isn't stong enough or long enough it may not be pushing the rod up enough.

Do you have a strong stream from the accel pump squirters? Also look to see that the pump moves as soon as the carb begins to open. I've seen carbs with a fair amount of play ay the pump so slight movement on the pedal resulted in no movement at the accel pump.

While I think the problem lies in the carb I have found that I have to move the initial timing up past where the factory recommends. Doing that does complicate things if total advance becomes too high as a result but it might be worth experimenting a little.

Ernier

[jtjim]

I have adjusted the pump linkage rod by bending and moving to different holes in attempt to fix the bog. I did have some play but have eliminated that. I get a good squirt now. I haven't tried adjusting the timing. I will replace the springs first and see what happens. Thanks, Jim