Ok so this cam is really starting to bug me. I cannot get
the high and low idle correct with vacuum advanced hooked up.

350 / 350
Holley 770 Ultra
HEI Distributor, aftermarket
Victor Jr intake
AFR 2.02 heads, decked
10:1 compression
Lunati 60103

• Duration @ .050 (Int/Exh): 227/233
• Gross Valve Lift (Int/Exh): .489/.504

I have timing set to 18 degrees advanced. Truck likes the higher timing.
I have tried everything from 0 - 25 and tried readjusting everything at 10 degrees advanced.

Air Fuel ration is around 12.5 to 13 at high idle and 13.5 at low idle.
I can get those numbers to be about anywhere.

High idle is a 1250 with vacuum advance unhooked.
Low idle when truck is in gear is 800rpms. The cam has to idle at least 750 rpms.

With vacuum advanced hooked to manifold vacuum at the base of the Holley and
high idle at 1250 the low idle is like 500, but the truck keeps dying. If I get the low idle to
800 the high idle ranges from 1250 to 1800. It keeps fluctuating.

What the heck? I am so tired of dealing with the idle on this truck.

Does the power valve have anything to do with vacuum advance? It is a 6.5.
I have a vacuum gauge if you want any of those numbers.


here is the link to the cam
Voodoo Hyd Cam - Chevrolet Small Block 268/276 - Lunati Power

 

whats your stall?

 

What are you asking?

 

2500 stall

Asking how to get it to high idle in a safe range and still run with vacuum advanced hooked up?

I need an 800 low idle, and an 1800 high idle is to high.

 

There should be a screw on the passenger side of the Holley that contacts the fast idle cam. You can back it out to slow the fast idle speed.
Check Holley's website for detailed instructions for your carb:
http://www.holley.com/data/Products/...0219-3rev1.pdf

 

I am looking at that manual now.

In gear at idle my vacuum is only 4.
In Park it is 7. That means I need a power valve of 3.5 or smaller.
Will that affect anything?

 

Oh, hey cool.
I have read that manual five times and never noticed that screw.

 

That screw only effects the choke.
I backed it out over a 1/4 inch. It is complete out and nothing changed. It is only active when the choke is on.


New plan. Total timing is set to 34 degrees at 2800 rpms. To heck with the stupid vacuum advance.
How do I get the high idle lower?


Change the power valve to a 3.5, that helped. Was able to get the Air Fuel ratio where I wanted it.
It is still idling higher then I want but it is better.