What is the RPM difference between the 83mph with the B1 and the 84mph with the Arneson, and do you think there is 7 to 8 mph left in it with propping?

At 84, I was all over the limiters @ 5,500 rpm's simply because I had the drives too high. This boat runs best in a 2' chop and I was running 84 in fairly flat conditions. I believe 90 is attainable, but I'll have to wait until next year. When I hit 83 with the XR's, I was at about 5,400 rpm's and it took some effort to get there. When I hit 84, I was not even trying for top end.

Sounds like you will easily get there for sure!

So will it take a different prop or do you think it about right now?

I'm not 100% sure if it's the right prop. I'll try again next year and check the prop slip. There is no doubt I need to lower the drives.

What makes you think you need to lower the drives? What's the issue?

How are the drives lowered, and how much adjustment is possible? Do you need to move the engines then?

OK, I wasn't clear, I need to trim the drives lower and just get more of the props in the water. The actual engine and drive position is just fine.

You also could try props with more diameter and rake.

I don't think diameter is the issue. 5 blade 17" should be more than plenty on a 38' boat. But something like 20 dgr rake and 32" pitch, maybe even in a 16.5" dia.
6 blades could be an option too.

Have you talked to Bblades about testing? As you know, Brett has the Hering test program now.

Oh well, there's a whole winter for all of us to think about props.

And I guess winter's here, got another bunch of x-mas catalogues today. Now... what do I want for x-mas? Hmmmm