Cutting out on hole shots?

Call off the herd

Mav sent me a "bog free video" after the accelerator pump clearances were adjusted.

Anyone else running position 2 on the accelerator pump cams?

In the first post, you mentioned that the carb was fully rebuilt. Do you know if the accelerator pumps were also included in the rebuild? The diaphragms can get stretched and lose their pumping efficiency. I see that you also stated that you took some slack out of the pump actuator arm. Good. The accelerator pump actuation must be immediately paired with the throttle.

From the Holley website:
"What we're really trying to achieve here is the proper relationship between the adjusting bolt on the accelerator pump arm and the actual accelerator pump lever. Ideally, you want that to be zero at idle. By zero I mean there shouldn't be any gap, and it shouldn't have any pre-load. That being said we also want to check it at wide-open throttle and make sure we've got a minimum of 15 thousandths of a gap, as far as available travel left, and that's to make sure we don't bottom out that pump diaphragm."

Just for giggles, it would be interesting to see what your vacuum is reading at idle. That can help you understand which power-valve you may need.

JQ

Watch the videos from earlier and/or read about pump adjustment.

But.................You can get all technical or you can do what you just did and adjust the spring loaded screw on each pump arm till it just touches the lever with no slack and you'll almost always be good.

Your stock nozzles are .031 inches for both the primary and secondary sides

Not too many people change from the factory cam position or change nozzle size so I figure you can get it right without any changes there.

Nozzles change the duration inversely to volume delivered as a rule. More sooner or less longer.

IF it's the squirter, don't dismiss trying a smaller one.

GottaSki wrote: Very good, thats good information. Next, do you recall the primary Mains, and the PV number?

Also, both the accelerator pump cams are in position 1. Is that correct or would #2 maybe work better on this motor?

Very good, thats good information.

Next, do you recall the primary Mains, and the PV number?

Its a big mechanical secondary, could it be you may have to be judicious with the go baby go lever and keep it in the primaries till it winds up some? or does it happen even when you do that?

KENO wrote: I hope his spark delivery system is working, he's got one of those JQ approved DUI HEI spark makers Not sure but I think it's even got a RED cap It's brand new and finally got the timing where it's supposed to be (and he says the problem has been there since he got the boat) Don't forget you have a double pumper (list number 9022) so there are 2 pumps to get adjusted and they have different diaphragms/capacities. Front is 30 cc and the rear is 50 cc I think a video would be good to show the bog/hesitation or whatever and also show how quickly your hand is moving the throttle on takeoff

Yeah that video is a good place to start on the accelerator circuit , the same bog was always there even before the distributor.

First, ensure that your spark delivery system is working well and timing is good. Engine stumbling or bogging down on accelerating is a typical symptom of a problem with the accelerator pump circuit. Below are 2 links to videos showing how to diagnose and tweak the accelerator pump circuit.

LINK1

LINK2

JQ