I recently purchased 2 Pro System Carburetors (Used)and both of them have power valves. Both are 1150's. Can anyone advise why they run power valves in them? Should I remove them?

I doubt they were built with power valves unless they were built for a street/strip car. Get the build # off of each carb and call Pro Systems to get the build sheets.

Both were built BBC drag cars. One for a 555BBC and the other a 582BBC. Both had 88 jets in front and 96 in rear with a power valve in front. Im thinking of blocking the power valves off and re jetting.

quote:

Originally posted by 1320racer: Get the build # off of each carb and call Pro Systems to get the build sheets.

This!

Patrick just built one for me and it has a power valve in the front. It’s a 1200 cfm strip only dominator.

A guy I’ve been helping got an alcohol carb and regulator from Patrick and it has a power valve also. Guess he really likes them. Not a major benefit on alcohol but lots of ways to skin cats.

Curtis

There are times a footbrake car can benefit from a PV, for a transbrake only carb it's just one more thing to fail.

My Pro Systems 1250 does not have a power valve.

Braswell carbs have PV from them, atleast the ones that I have seen.

Drivability is better with a pv in the primary single 4 application. Will get sloppier plugging it. It will work just fine, unless of course it is bad or old and dry.

again, no PV in my 1250 nor is it "sloppier"

I have 2 pro systems carbs and neither have pv's.

I don't have a carb without a power valve.

My Pro Systems carb,that I ordered strip only car w/brake,came with a power valve.
I called Patrick & questioned it....He said run it that way,trust me you'll like the results.
I haven't finished the car yet,but hope to try in soon.

I would run it with powervalve in front but not in rear.

Play with a wideband O2 and see why they have PV's installed.

The reason drag cars don't use PV is the fuel inlet for them is higher up vs the jets and therefore more chances to become uncovered with fuel, and yes for the primary/front side too! There is no reason for them in this application. Mark mentioned they can help footbrakers,,, ok but that really depends on how they load the converter, as it could be open at this point also.

As for driving around it the pits, 99% of the time the main circuit is not operating so they do nothing... don't need a wideband O2 sensor to tell me this. If the main circuit is providing fuel in the pits, your floats are too high or your speeding!

Exactly^^^

I know the Max-Speed Throttle Stop Carb from APD has a power valve. They seem to work fine. I don't know what the big debate is about. Apparently Pro Systems thinks in the application that they built the carb for that a power valve is warranted.

One of the wonders of drag racing is that there are no absolutes. What works for me may not work for you. That's the problem with these threads. There is more than one way to skin this cat.

Now, I don't know shyt about carburetors but, for me a PV works great in a Super Street application. A PV gives me absolute control over the cruise RPM O2 and control of just when that O2 changes.

For a bracket racer that utilizes two throttle positions (closed or wide open) a PV may not be what's needed. One's engine combination will make that known.