Straight vs Fixed surface drive
 

Need some help understanding the intricate differences between the two other than the obvious trimming aspect.

I am not sure what ones you are trying to compare but the two different types that I know of are, one type is steerable and one you need a rudder both are trimmable

Rudder type steering running through a strut. I wasn’t aware it was trimmable while under way. And I can’t seem to locate the transom mounted “thrust bearing”

If you could not trim the drives it would be real difficult to get the boat on plane , do you have a picture of the "thrust bearing" that you are looking for ?

Thats off a set of Buzzi drives, but thats the piece Im talking about. As far as trimming goes, my understanding is you trim with oversized tabs. Im sure someone with actual real world experience will know for sure

do you have those on your hsb ?
think they're called trimax drives, don't think they are trimmable.

post the link for this so we can see what you mean, pulse drive maybe ?

This was a picture from a thread on facebook. Have nothing on the HSB at the moment, but am exploring straight shafts as an option. Going back and forth between the two, cost vs usability.

there are some surfacing inboards (shaft strut and rudder) drives that are being produced.
a few are bolt on units seen on light military and pleasure craft., they spin some big wheels.

google surfacing inboard, up top click on images and scroll thru.

sea fury, power vent (smith boat), tri max

Ya, the torque system by Tempest and the Buzzi systems are what Im comparing to the ASD8.

you will have to make hull modification to use the buzzi and the tempest style whereas the arneson will bolt to your transom

Ya, I’m aware of the extra work involved in making the straigh shaft work. I guess the question would be: is it worth the added effort for the straight drive, I would assume no, but I’m not an expert

I could not imagine the amount of work it would take to mount some of those straight shaft surface drives to a existing boat , looks like most of the boats with them were built around the drives.

Agreed, and a ton of engineering in the COG vs shaft angle etc. if functional though, could potentially cost a fraction of trimmable surface drives

levi drive ld 240-250, designed for 12 degree transom.

Not a bad design. How does pricing compare and availability of props

They look nice but the drive info said the hp limit is 300 what are you building

He listed the 240, they have two models above that one. Pair of Cummins engines will be in front of the drives

For a work boat you might be fine but if you want to go fast, finding a reasonable priced set of props might be real difficult