2007 35 executioner prop question
 

I'm in the process of buying a 2007 35 fountain executioner with 496 HO. it has 1.65 drives with a 32 5 blade. on the surveyed test drive it had full tanks with 3 adults. the boat only ran 72 mph at 4400rpms WOT. the drives were at 4.5 and tabs at 2. is this normal with the 32 5 blade or does the drives just need to be trimmed higher. I was told it should run 78-80

Call Fountain with the hull number and they will fax you the test run sheet that has the speed they achieved and the props used.

I already did that it had the bravo 4 blade 32 ran 79 at 5150. The prop has been changed to a 5 blade 32

You are putting a tremendous load on those engines if 4400 is WOT , I have the same boat with the same motors and I had BBlades make a set of 34 Bravo 4 blades that are lab finished . The best I have seen is 80 @ 4950 and the tabs all the way up drives @ 5

I think all the Fountain reports are a little on the happy side,
I am new to the 35 EX myself,but talking with other 35 owners I have been told the boat is a true 75MPH boat and when all the planets and stars line up that one day you might see a honest 80, but expect 75,hopefully I am wrong and with the right props we might see 80.

I'm not worried about the speed I guess what I'm asking is should I be able to turn 32 5blades closer to 5000rpm or when you go to 5 blades do you need to go to 30's

Can you ask the previous owner why it had 5 blades on it? The 32 four blade props are the correct ones for the boat with a 1.65 ratio. Sounds like the 5 blades were an attempt to improve mid-range speed, but certainly not top end. As you can see with the 5 blades and all that weight on the test run, the engines didn't have the steam to deal with the load. You would have to drop pitch on the 5 blades to get closer to the proper WOT for those engines. I'd go back to the 4 blade 32 Bravo 1's as that is the perfect prop for the 35 Ex. I've been in 3 different ones and they all ran 32 four blades with 1.65 drives. Depending on gear, fuel, persons on board you should see 76-78 at WOT of about 5000-5100. A stock 35 Ex with 496's is not an 80 mph boat.

techman is right on the money here. Spot on with the info he has put out for you.

The tall gear boats were a tick faster on the top end, did give up some in getting there vs the 1.50 geared boats.

He said it was running on the limiters and he wanted a better cruising speed.

That's what I thought. Propping is always a compromise!