Visit The Dirt Forum for More Information

Author Topic:   4412 help
nw15x
Member
posted August 01, 2003 02:31 AM
I have a 4412 with a plug instead of a power valve. Has anyone tried this setup. Antyhing to look out for. Or do you recommend using a power valve for circle track racing????


waltonjr1
Member
posted August 01, 2003 03:47 AM
Use a power valve,you will not get maximum performance out of your carb with a plug,you will either lean out on top end or overload on bottom.

------------------
DEANJR#22


nw15x
Member
posted August 01, 2003 11:17 AM
what size power valve would you recommend is for a vortec head 355 chevy


KPLugnut
Member
posted August 01, 2003 11:31 AM
The best way to choose the right power valve is to measure what your manifold vacuum is with the engine at idle. Install a power valve who's rating is 1-2" of Hg below what your manifold vacuum reading is and fine tune from there.

Hope that helps,
KP


nw15x
Member
posted August 02, 2003 09:31 AM
how can you tell what power valve you have. i have a couple I can try but either they have 3 numbers on the face plate, or no numbers on the face plate and a number side where you put the wrench.


69-er
Member
posted August 10, 2003 11:09 AM
Another thing you need to consider when selecting a power valve is to make sure that the valve doesn't start closing at the upper RPM ranges. If the valve is rated too far low below idle vacumm and with a two barrel carb, the restriction could be enough to start raising the vacuum to a level that is higher than the powervalve is rated causing a lean-out. I temporarily mount a vacuum guage on the dash to monitor the vacuum at full throttle just before letting off into the turns. I've never had the vacuum raise much, but it gives me a peace of mind. You only have to measure it once, and you're set for the season.

Larry

WOODDOG
Member
posted August 11, 2003 06:13 AM
To learn more about power valves you can go to http://www.parkercarburetion.com/faq.html, scroll down to the Carburetion heading and read the first two articles.

------------------
Earl Parker II
www.parkercarburetion.com
704.482.7588


Back to the Archives