First off i just rebuilt my racing beat carb. being it got to much trash it in. i noticed they put a plug in the power valve spot??? why is this.

also with a 465cfm and 30cc accel pump, .056" jets and short yellow secondary spring, and i put a power valve in and at 6psi and at 8 degrees advance (specified by racing beat) im leaning out. not bad but its also more then i want.

this is on a 12 streetport with holley red pump and aeromovtive regulator and 3/8 fuel line

any body got any suggestions that dont have "vac leak" in them.

 

they plug the power valve for a reason. i'm sure someone else on here knows what that is. might be the reason they run rich.

 

Here are the RB Prepped Spec's for a StockPort Carb.
For (StreetPort) run 52 Jets in the Primary, 48 or 50's are to Lean and change the Secondary Spring to White. Although the Short Yellow will work just fine.
Plug the Power Valve in a StreetPort.
sgieldon
steve

 

i am running .056 jets and the yellow short spring and it is still leaning out. IMO. the plugs are light and a little whitish grey, and there is no vaccum leak. what is causing this??.

Why do they plug the power valve????

 

explain what's happening that leads u to believe it's leaning out. isn't that how the plugs supposed to look?

 

This may be the response that your looking for. This is the reason why I pluged the power valve on my holley and I didnt get my holley from Racing Beat. Rotaries in general, like to back-fire as we all know. This back-fire can break the power valve so that it doesnt work well making the car run horrible. Pluging the power valve will help us "Holley guys" in the sense that when-ever we do back fire, which is commen for us, we dont have to go back in thier and replace that damn thing every single time. Thats why Racing Beat plugs it. In turn if it is pluged you will have to run a bigger jet on the primaries just to make sure you dont run so lean. Thats what I did anyway, I blew a power valve the first time I took the car out and it was a weak back fire. Replaced it with the plug and put bigger jets in the primaries and it runs great now.

If you need a power valve, Holley does sell a kit that you drill into the body or the Holley that protects the power valve from blowing out if and when you do back fire.

 

POWER ENRICHMENT SYSTEM - A
vacuum passage in the throttle body transmits
manifold vacuum to the power valve chamber in
the main body. The power valve which is located
in the main metering body is affected by this mani
fold vacuum. The manifold vacuum acting on the
diaphragm at idle or normal load conditions, is strong
enough to hold the diaphragm closed, and overcome
the tension of the power valve spring.
When high power demands place a greater load on
the engine and manifold vacuum drops below a
predetermined point, the power valve spring over
comes the reduced vacuum, opening the power
valve. Fuel flows from the float chamber, through
the valve and out the small holes in the side of the
valve through the diagonal restrictions in the main
metering body and then into the main well. In the
main well, the fuel joins the fuel flow in the main
metering system, enriching the mixture. Some
models have an additional very small drilling that
leads directly from the float chamber to the power
valve cavity. This small hole conducts enough fuel
to prime the power valve so that there is no lag
waiting for fuel to fill the cavity when the valve
opens. As engine power demands are reduced,
manifold vacuum increases. The increased va
cuum acts on the diaphragm, overcoming the
tension of the power valve spring. This closes the
power valve and shuts off the added supply of fuel
which is no longer required.

Some racers prefer to run Holley carburetors without
power valves, and use this plug to block off the power
valve circuit. When doing so it's also necessary to increase
jet sizes to compensate for the loss of fuel enrichment
provided by the power valve. An increase of 6 to 8 jet sizes
will usually be enough but you should read the spark plugs
to verify proper jetting.

 

considering i have gone 6 sizes up and still get a little white showing on the plugs i add a power valve which in return seemed to help a little and smooth things out. untill i blow the few power valves i have i think i will stick with the power valves

this is right off holleys site

THE TRUTH ABOUT POWER
VAL VES USED WITH HOLLEY
CARBURETORS
There still seems to be a lot of misconception about
Holley carburetors blowing power valves. Nothing
could be further from the truth. Holley performance
carburetors built since 1992 have utilized a power
valve check system that effectively eliminated this
infrequent problem. Consisting of a spring, brass
seat and check ball, the check ball system is 100%
effective protecting the power valve diaphragm
from damage due to engine backfire.
The power valve check ball is designed to be
normally open but quickly seals to close off the
internal vacuum passage when a backfire occurs.
Once closed, the check valve interrupts the pressure
wave generated by the backfire, thus protecting the
power valve diaphragm. There is no way that the
power valve’s diaphragm can rupture due to an
engine backfire!

 

I'm also having rescent trouble tunning a 13b half bridge motor . I'm currently running a 600 dp 58's in the primaries and 60's in the secondaries . It feels like its not gettin full potential ... can any one help ???? Racing Beat says they dont tune anything for half bridge port ...

 

is this for holly carbs only? or just any carb you stick on a rotary?

 

its for any holley based card barry grant,qft,proform etc....