I need some help with tuning my new Holley. I currently built a new combo with a 499 stroker low deck. Holley street dominator with solid flat tappet .050 = 251 intake and 256 exhaust, .567 lift at 110 lobe. 3:91 gear, 4 speed.

I have always used the Edelbrock 800 avs on all my builds. I have had really got success with tuning them, but I am not familiar with the Holley's.

On this build I decided to use a double pumper.

I am having problems with a very rich condition at cruise. I have setup my idle mixture with a vacuum gauge and o2 gauge.

I have 9-10 inches at idle and my o2 read 13.5-14.0. I replaced the 6.5 stock power valve to 4.5.

It idles fine and currently has no hesitation when accelerating from cruise.

When cruising around (ambient temp 90f) the o2 shows 11.8-12.8, If I let off on the accelerator it goes up to 13.5. These readings are the same at 40, 50 or 60 mph. Occasionally the o2 drops to 9.8-10.8 when cruising and the car starts to buck. A couple times it has stalled with those readings.

Fuel pressure at idle is 5.5 to 6 psi with a mechanical pump. Not sure what it is at cruise.

It runs okay at cruise when the readings are 11.8-12.8, but I would like to lean it out. What can I do? I was thinking of changing the primary jets. I cannot replace the air bleeds because they are a fixed diameter.

I don't know what it reads at WOT because I am trying to breakin this new clutch. On the engine dyno with open headers the plugs showed good readings. I am thinking with the full exhaust it will probably be slightly richer.

Timing is at 34 total and 16 base. I have set the float level to the bottom of the sight glass.