JUPITER PULSARE

I've got a Checkmate 2800SX outboard with twin Mercury 2.4L 200's. I'm running the motors on Gill brackets with 24" of setback at 18" centers. Running a straight edge off the bottom, the bullets of my noseconed lower units are about even with the bottom. The boat is very easy to trim up and the bow gets a bit flighty in rough water (the cabin is gutted for the time being-I'll eventually recover all the seats/V-birth pads with new vinyl and reinstall the wetbar). I've got the boat set up turning the props out right now but I'm in the process of swapping the lowers to try turning the props in. I'm hoping to pickup a few mph and some stern lift...any suggestions??

bbladesprops

Hello,

I believe we have spoken a bit about this before but if not.
Inward rotation will create more bow lift and less stern lift (from a physics standpoint).
Ultimately your seat of the pants observations will determine which rotation you prefer and the propellers can be modified to assist the boats attitude from there.

Brett

JUPITER PULSARE

Brett, you were actually talking to 2tonChevy who has the same exact boat but with a couple inches more setback and a different bracket. I'm running the old Gil brackets at 24" of setback and turning DAH 26pitch choppers @ 6000rpm spinning out. I'm in the process of swapping my lowers right now to try turning the props in to see what happens. The boat is a "V" pad bottom boat and layed up with AME 4000..so along with my cabin being empty it's pretty light for 28' of length. I'm as high as I can go (without switching to 20" mid sections) so short of trying different props I'm at the end of my "dialing in" the boat...unless I drop my motors down on the Gill brackets...

bbladesprops

A 4 blade propeller such as our Blaster would be a great upgrade from the Chopper propellers. These props offer both bow and overall stern lift. They are very fast and are not as compromised by weight.
Let us know if you would be interested in testing these. So far they have been stellar on single and twin OB Checkmates.

Brett

msm

How can you lift the bow without pushing down on the stern?

bbladesprops

Great question.
I usually tell people the only way to create bow lift is by pushing down on the ster. This is true unless you have a hull that induces its own bow lift to its aerodynamics.
The BBLADES Blaster is a 4 blade propeller with 14.75" of diameter. This in itself creates more stern lift than 3 blade 14.5" chopper. This is just the physics of the propellers. In addition, the Blasters have a aggressive rake angle and specific cupping in specific areas to add in leveraging the transom when positive trim is added. Therefore the props pick up the stern slightly while still being able to add tons of bow lift.
On my 20' padded V bottom these propellers provide more overall lift and trim than any other propeller I've tried or modified and I have tried a trunk load of them.

Brett

speeddr2000

+1 on this also makes docking with just the motors a ***** too.

msm

Thanks for clearing that up, Brett.

JUPITER PULSARE

Wish I could round up some of the old Ocean Outboard crew who raced the 2800SX outboards...I'm sure they my remember how they set the boats up in the mid to late 80's!

bbladesprops

Labbed Mercury Chopper 1's (14.5" diameter) with the engines deeper than you might think.

With the larger diameters and multiple blades we have today, there are more options.

Brett