Stormrider

Ron, I'm thinking along the same line...
Doing 650-700hp w/ a Konrad w/ transmission.
Would moving the COG forward a bit help balance?

B-Stubb

I dont beleive konrads run tranys only speedmasters ,no more HP than you guys are talking buy a XR and bee happy.You realy need big HP to run the tranny and a speedmaster 5-6 like 1000 or better. A tranny and the big drive would kill a 700 HP motor the XR would bee much faster..

WildThing

Brian, I know you have posted this before, but I forget.
Do you have a notched transom?
What drive are you running?
That is on bad a$$ motor you are building!!

Griff

You can't run a shorty drive on a notched transom 28. Actually you have run a 2" spacer between the upper and lower to get the propshaft deeper into the water. With the notch, the X has to be raised about 2" higher than a standrd V boat.

JO - PANTERABOATS

In the late 70s and 80s we delivered many 28' powered with twin 454-330 HP Mercruiser packages with TRS drives and tranys. They ran real nice. We have delivered a few 28s with Single high horsepower motors in recent years with Speedmaster 3A drives with transmission. We have not completed any 28s with Arnerson drives.

The 28' single engine with full cabin is perfectly balanced so I would recommend with a 650-700 HP big block a brand new XR Bravo 1 drive. If you get over the 800-900 HP range then I would consider a 3A Speedmaster or larger speedmaster drive.

Here is a picture of a 2000 Pantera 28' powered by a single 900 HP blower motor with a 3A speedmaster drive and trany. Top speed is near 100 MPH. Boat flys level in rough water and handles perfect at high speed. Boat has a Notch transom.

JO

JO - PANTERABOATS

Here is a 1979 28' from the early days with twin 454-330 HP Mercs. with TRS drives.

JO

panteraman28

I run an Imco, with the notched transom, and a 1" spacer, works very well. The Konrad uses a tranny, but if you get thier hp drive the tranny is in the extension box, I think. As for cup in a prop,if your looking for the best performance and are going to get it labbed grt rid of the cup. The best place I have found to lab props is Precision Propeller in Indianapolis Ind ,one week turn around, talk to kevin

JO - PANTERABOATS

I have ran with Jeff well into the mid 90s with an IMCO Bravo 1 drive and worked well with his power combination.

Stormrider

Thanks for kicking in the response Jo.
Has anyone w/ 600hp and over had any problems w/ the bravos?
I know the larger heavier, hi HP boats are breaking them, but in a light boat application would it ease the stress on the drives?

And I was also thinking if an older TRS boat was found, to do Konrads.
The extension box for the tranny is only for a bravo conversion, so you don't have to move the engine.

BTW, that 28 w/ the 3a is smokin...

B-Stubb

Yes mine is a notch Im under the beleif that cause we have a high X that we are a little easyer on drives than most for our weight . Mine is a stock bravo with 200 hours of hard running on it with 850 hp never been broke yet. Maby its a lucky drive? But a XR should be all we will ever need.