Bravo DWP vs LWP effect on engine temps
 

I thought I would share my experience with the two types of Bravo one lowers. This is on my '04 Nordic Heat (single step hull) with a 496HO/Whipple (closed cooling). Running a 1" drive spacer to get the propshaft 4.5" below the pad. Thermostat is the one provided by Whipple @ 120 degrees.

Dual water pickup (DWP) lower would run at 180 degree engine temp when running pretty hard. Switched to a low water pickup (LWP) and the engine temps dropped over 20 degrees at the same duty cycle. Analog PSI gauge shows 22lbs for the water at WOT with the LWP. Unfortunately I don't know what the psi was with the DWP lower as I installed the gauge when installing the LWP lower.

Perhaps I was sucking air from the top couple side holes on the DWP lower, or maybe the LWP just moves more water. Not sure, but I'm very pleased with the results as Whipple wants the engine to run around 150 degrees.

Interesting.

Thats common.

If you feel like testing, What are the WOT speeds if you drill and tap the 4 holes in the nose and put plugs in them? (thread in allen plugs) Then tap or plug the top 1st hole, then second hole to see where water temps are, they should stabilize. Sometimes its only the first hole.

In most V, Step V it picks up 2-3 mph and you can usually straighten out the side water pickup temp problem by filling the top 2 holes. This was common on Fountains due to drive height & pulling aerated water.

Or leave it alone and go boating...

I read about guys losing MPH on top with the LWP. I'd have to do more testing with the other DWP lower to confirm that. At this point I think I'll just go boating!

I closed off the upper 2 holes and opened up the bottom holes and ported them to grab more water. Works for me, I can run 80+ for miles and I don't go over 160 which is my thermostat temp.

I should do that to my DWP lower so I have a good spare.