4781-6

Anyone have a fixed airbleed main body, they could measure the air bleeds? I just picked up a used one, and want a baseline. I searched extensively, and could only find HP data. Thanks in advance.

In the past I have used Holley's tech line for info like that and they were great.

Thanks, sounds like a good idea. I noticed the primary and secondary boosters have a different id. I saw the oem secondary jetting, is 2 sizes leaner, so I’ll measure the bleeds, booster discharge channel and od and id, to get an idea why, before calling.

I have a 4781 on the shelf...I'll look and see what -# it is.Just for the heck of it. Let you know what I find.

If you could measure the primary and secondary pvcr as well, that would be great! Thanks!

here is what I have, not sure if it helps you though. It's a 4781-2, the primary bleeds are .070 idle, .026 high speed. The secondary bleeds are .067 idle, .026 high speed. I didn't want to pull a bowl and metering block. its in ready to run shape and didn't want to mess with it but I have written on the bowls primary has a 80 jet with a power valve, and the secondary has a 92 jet with the power valve blocked. I know that doesn't answer the question of the pvcr, but that's the way I have that one set up. Holley's tech has always been really good.

Thanks! Did you happen to notice if the primary and secondary boosters are different sizes? That’ll be my last question!

I didn't notice any difference in boosters.