Whats the preffered way to set up a marine carb as far as secondary opening. 40% left, 60% left or 1:1?

Also is there a point to powervalve in a boat. Boost referenced .. dumping 8-10 jet sizes of fuel because I hit 1# of boost (pretty sure thats how it works) seems unnecessary. It`s not a car where you hit the gas every other stop light and need that fuel enrichment.

To me (carb newb but fresh eyes) I`d set up a marine application carb with 1:1 primary/secondary and block off the powervalves. Tune it that way.

dan,the power valve stops it from being to rich in no boost running,when you start making boost you need to ritchen it up.the boost ref blower carbs[quick fuel]come with a 4.5 power valve and on my engines i did not need to change from that.with your a/f gage you will see a steady line almost the same from 2500 all the way up at wot.

I boost reference both primary & secondary, and have progressive linkage opening of the secondary butterfly's. Why would you not want the motor to tell the carbs what it needs??? I have a great fuel cure from idle all the way to WOT. There are times that my secondaries are just a little open and I m still pulling vacuum. To me blocking off power valves is going back to the stone age

Rookie boost referencing question . Do I run vac line from these ports on the carbs to ports under the blower in the intake and can I T them or do they have to be separate ?

i can see a drag car with no power valve and 8-10 jet sizes larger because it is either ideling or wide open but in a blown boat deal forget it.most of the time the boat engine will be in vacuum or low boost.

Very nice by the way...Yes you can tee them, I have all 4 of mine coming of my carbs tee'd into my vac/boost line going to my gauge on the helm.

Mike I totally agree with you on that

t them togeather and run one line under the blower in the intake manifold.DO NOT run the vac line to the carb adapters.

that is because us blown fountain guys think alike!

Thanks B wan .