Ron, The addition of adding prop blades will also add stern lift, right? My conversations recently with Dave Dewald and my experience with going from 3 to 4 blades leads me to this.

I think the number of blades make a difference for sure but regarding the transom lift IMO I think it depends on the rotation and extension of the gear case with the thru-hubs.

Jim, with you having the ballast tank there's a lot more room to tweak I'm sure... the Mercs may very well be the best all around prop for you. I can only add bow weight the old fashion way

You should be fine with the big stereo refit and all those subs up front!

So Jim, We actually met at the boat races when you and a friend of yours were at Sams watching the races this past season. Wasn't sure if you remember that. So I was wondering the Dewalds and the Merc cleavers you have used what the depths are that you have run each of them. I don't remember seeing that anywhere. Im currently running the 33 x 15 Mercury 5 blade cleavers. I also ran a set of Daves props with the bravo style hub. I ran 33 x15 but I don't think I ran them deep enough I kept the same heights as the Mercs. As they didn't run well on my rig. They were on the limiters at around 110mph. As I said I think Deeper would have worked better for that set. I wanted to try more pitch anyway so I traded them to some one in Long Island. His rig ran 116mph. A classic style 308. I ended up ordering and running Dewalds 34 x15.25 which we tuned a bit. They ran well but we never really finished their tuning as winter came and in Jersey Im done. We got them to within a couple mph of the Merc Cleavers. They ran smoother and the mid range was better but as you said the acceleration was better with the Mercs as I imagine they are over the blade exhaust and the props spin up faster. Anyway again I was wondering about the Depths you ran each set at. My rig has no notch in the lower transom and I have only 3 inch setback from my jack plates. My propshafts are at 2 inches above the bottom and could go a bit higher but I would need water pick ups like Ron did on his 308. A magnificent job he did I might add. I start losing pressure about there. Oh at optimal conditions Im currently running 116mph at around 7034rpm. I hope to improve that as I recently got a new powerhead and have been losing at least 35 to 50 horses on my starboard side since day 1 I had the boat. Maybe some of this above info can fill some gaps. Ron pretty much knows everything about my boat and is a tremendous asset here to us all. He could answer some things about similarities our rigs have. Mine is a 318 with 400Rs. I love it. Very close to yours but just different enough to possibly function/perform differently. Good luck with all of this.

Maybe this is a good place to continue the prop discussion. My questions are:
1. 3l Sportmasters torpedos are 4.88" dia., 400R's are 5.44" dia. Are the new Mercury CNC Thru hub props 5.44" dia. or the standard 4.75" dia?
2. What are the dia. of the thru hub Dewalds for the 400R application?
3. If the dia's. above are the std. 4.75", are the thru hub props effectively a combination of over hub and thru hub due to the "gap"?

He was wondering if the thru-hub props were made to fit the larger 400R cases. Pretty sure they are motor specific Taboma.

Ron, My mistake. I fixed my post to thru hub, not over. Sam, your post helped me understand the sizes and attributes. Thanks guys!