Keith Atlanta

What am I doing wrong here???
I have a Baja 342 - with the 33 Outlaw hull twin 525 HP engines and I have Stellings boxes with -2 in shorties. (mid hole on the Stellings box))
I have a prop shaft height of 3.25 and not getting great numbers - running bravo 4 blade or IMCO Shorty (-2).

What prop height have you seen the best results with?
Is the mercury lower or IMCO lower better? (Want to get the best bow lift)

Numbers:
With 496 Mag Ho's Before upgrades
All GPS
3500rpm @ 50.2mph
4000rpm @ 60.1mph
WOT @ 71.8mph

With 525+ HP Stellings boxes and IMCO shorties
All GPS Prop height 3.25in
3500rpm @ 41.8mph
4000rpm @ 50.4mph
WOT @ 64.7mph

With 525+ HP Stellings boxes and IMCO shorties
All GPS Prop height 4.25in Stock mercury lower
BAD porpousing and felt like the anchor was dragging handled like crap!
3500rpm @ 42.8mph
4000rpm @ 52.4mph
WOT @ 68.6mph

Anybody have suggestions? Thanks!

monstaaa

uses the stock lowers. i did the same boat minus boxes and gained nothing,
. lost the leverage needed to lift the bow high enough to reduce wetted surface area of bottom. plus the imco will slow you down and really doesnt help out till near or at the 90 mark in most applications.

Keith Atlanta

Tried to stock lowers and lost 2-3 mph at WOT and about 8 mph mid range. What prop height did you try - do you remember?

DirtyMoney

Keith are you in the Atlanta area?

DareDevil

Since the # get better by lowering the drive, go with lower hole on box and stock lower on drive.
Let the props spin inward ,on a baja (they like that ).

Griff

Spin the props in.

Keith Atlanta

rbr2328 - Yes, in the Atlatna area. I live in Gainesville next to Thompson Bridge

Keith Atlanta

Props are spinning in. I am trying 3.25 and 3.75 depth today with 4 blade bravo and 5 blabe maximus props.

I cant put the stock lowers on just yet... I dont feel like swapping al the gears back. I've had the drives apart literally 7-8 times and its getting old now.

fossil fuel

Throw Stellings boxes in the trash ! Driveline eliminates drive coupler and is hard on drives on heavier boats........IMCO shaft will fit on center adjustment. Then you can use Merc coupler. Do not bolt driveline to flywheel or you will be buying drives. My 2c

DareDevil

You are somewhat right.
But if he goes with IMCO ,he needs to adjust the engine up/down to center it .
With Stellings you do not need to do that.
Plus in my 33 PP i never had a problem.
Now on 382 Formula ,i think running Bravos is stupid anyways (with big HP) !
I would run Konrads on a boat like that !
Unfortinatly the torsionshaft from IMCO comes apart too.
There is nothing ou there which lasts for ever !!!!