Without 12" boxes or the 8" box on an ITS, you will be a little slower. It appears that the cleaner water 8"-12" behind the transom makes enough difference to gain 1-4 mph. That has been proven several times and I have first hand knowledge as well.

As for the 496 Mag HO, I think Rippem had dialed his in to an average of 72mph, if I'm not mistaken, but has seen a high of around 74-75. They make 415 hp, so maybe a difference of 100 - 130 HP between the 500 EFI and the 525's. That does make sense.

Dave

speed
 

xx

1-2' chop, light on gas just over 81 at 5200 rpm with 500's. I would also add that my boat came with XZ's which I think have slightly less internal drag than XR's. The props are labbed 31's.(Bravo)
This hull seems to run somewhat wet for a stepped hull, this is one reason they benefit from a box it in effect puts more bow lift on due to leverage (and props do run in cleaner water). These hulls do seem to respond to added horsepower better than some others though.

Thank you! That was some of the Info I was looking for. Mine also has the XZ drives.

Now the question is do you want to let me borrow your 31's? :lolhit:

So im assuming yours was 78-79 any day then...

sure just tell me where to ship them! lol

Yes, upper 70's. The hull does not free up with stock horsepower in calm water.
The other thing to remember is I think it may have been 2000 or 2001 Formula raised the x dimension some? Anyone know the facts on that?

correct average with outta the box 26" Bravos and a med/high wieght load of fuel and gear
best I ever saw was 74.6 and held it GPS downriver cold spring water clean boat full of fuel
never seen it again.
I have found top speed to be somewhat inconsistent in a 4-5 MPH window, I believe having more to do with air quality and water conditions any given day, than load. The boat does not seem sensitive at all to fuel load in regards to top speed.

When i was running the 5 blades that came on the boat from the factory (think there 28p 5 blade maximus?) I was seeing about 85-86 on gps in the ocean and 80-81 in the lake. This is with 525's with boxes all from the factory and xr drives. When i put the 4 blades on i was seeing about 85-86 on gps in the lake have not yet run it on the ocean with the 4 blades. boat is a 2005 353 fastech

Hey Dave, you gonna come see Lake Effect and I this summer ast the island????? come on down!

Sorry, don't see it in the plans this year. You do know that you both have a standing invitation to come play in The Thousand Islands though!

Dave

hmmmm road trip with Lake Effect! ha