05 Fountain

I'm gonna run mine a few times more before changing to a 29-30. I'm still running 51-5200 rpms with the 28 B. This winter might add a supercharger and dana exhaust, if so I'll be changing props again, so I'll stick with the 28 for now.

Raylar

If you are speaking of say around 2001 to 2007 single engine, step bottom 27 then the only difference from the 28 - 30 prop will be the gear reduction itself. Your numbers are exactly what the manufacturer claims on all the brochures we have regarding the 496HO boats (which i think all or most are of this vintage). 68 - 70mph stock. The 1.65 drives came with 28. The 1.50 drives came with 26.

Michigan Matt

That's why i can't understand why mine came with a 30 with 1.65 gears. everyone one else has 28's? How could the same package not even be on the limiter with a 28. Does mine slip that much more than the next one?

bob_t

Do you have the performance report for your boat? If so, what is the X dimension. They fooled around with it a little bit (some had 19", some had 19.5") and some with higher X's had more slip and would spin a little bit more pitch, especially in cooler weather. On one of our 29 Fevers that had really high X, it actually needed a 1/2" to 1" drive spacer to get the prop to hook up decent. Otherwise, we had insane amount of slip, even with B1 props. Couldn't even get the boat on plane with a Hydro Q-IV ... it would just blow out the prop no matter what you did with the tabs and/or trim.

The performance report on our 2004 27 Fever showed X of 19.5" with 28P B1 RH prop at 5150 rpm (on the rev limiter) and 70 mph.

carcommander

My 05 showes 1.65 ratio 19.5 X dimension 28P prop RH and 69 mph. I have seen 68. I tried a BB prop which was a 30P prop cut down and labbed. It did not perform as well as the stock prop. I don't think Fountain leaves much on the table. After trying the BB flop I gave up on any prop changes.

05 Fountain

Interesting.......

Michigan Matt

I have done a lot more testing this season. I tried a BBlades labbed 28 P5X and it and was on the limiter at 68.3 mph but it was a nice cruising prop and I think a 29 P5X labbed might be the ticket especially with a loaded down boat. Tried the original 30 Bravo again with light fuel and got 71.4 on GPS at 5100rpm. I am kinda surprised how weight sensitive the boat is overall because real world testing isn't me bye myself with a quarter tank of fuel. Like others have said Fountain is pretty good from the factory and the 30 Bravo seemed to work the best so far. I am trying a Hydromotive quad 4 30 pitch tonight and will let you know if I can improve any numbers or even get on plane.

Matt

Gh700xx

whatever ya do ya need to keep the 8.1 engine speed below 5100 the factory valve spring package doesn't like much over 5000 for long periods of time. when we used to run for merc I lunched a couple 8.1s for the same reason dropping valve springs and valves cause the test required 5100 rpm.

Bama

I have a 03 27 496 Mag HO bravo Ix running a LH BI 30p spinning 5000RPM in summer heat 70MPH all day. When it is cool and dry 5100RPM 71 MPH. The boat really likes chop, the more air you get under the boat the lighter it gets. Water conditions will make or cost a couple of MPH.

Michigan Matt

I agree 100% I heard the left hand prop actually is worth a little too. All I know is that when I pull up next to another 27 ft fountain with the same set up I want to be the one looking back not the opposite :-)