Excalibur

On a dominator. There are 4 jets close to the skirters, are these air bleeds? And there are 8 jets just outside of the others, what are they. I have 91H's on the metering blocks which I assume are the mains. Any suggestions as a starting point for a 604 with a mild cam. Seems a little rich when you rev it and tends to foul plugs. Skirters are 35's.

PatriYacht

Those holes you referred to as jets are air bleeds. I looked up your carb on Holley's web site tech info. It says your carb has no power valve. You will have to jet slightly rich on the low end to avoid going lean in the upper mid range just before the secondaries open because you lack the richening that a power valve provides. Other than that you will have to go through the process of jetting and doing plug checks at different throttle settings. Make sure that your float levels are correct, i.e. at the bottom of the sight plugs on the sides of the bowls. When you remove the plugs, just a little fuel should weep out.

Excalibur

The carb is a 8896-1 4500 dominator and has power valves. Just rebuilt the whole thing yesterday. What was that web site you were on?

PatriYacht

www.holley.com. Go to tech section. There is a pdf chart listing all of Holley's carbs and what's in them. Did you buy this carb new?

Excalibur

It was used for a dyno run so I don't know if changes were made.

PatriYacht

I'm using 90 primary, 92 secondary with a pretty big hyd. roller. Power valve should be 6.5 or lower or else it will open at idle and just above idle. Squirters are good at 35. Make sure ignition timing is 16 initial, 34-36 total. Not enough timing will make the engines really doggy at low rpms.