Finally got to run the boat for the first time this season.36 Outlaw with 500EFI's and boxes with 1.36 gears.
Last year, best was 71.6 on gps with the 23's.@5150rpm
Yesterday,72.3 gps with the 26's @4550rpm with about 100 gals more weight.
Would labbing get me back the 600rpm I lost?
Liked the way the boat got on plane with the 26's(no blow out like the 23's did)
However the thing that bothers me was the severe vibration or shudder I had if I backed off too fast,is this normal with 4 blades?
Thanks
Steve

Why not use 24" B1 props? You will have better mid-range acceleration and gain 400rpm, then lab it to gain 200 more.
Your slip improved from 13.2% to 12.3% between the 3 to 4 blade.

cobra
What is considered the ideall range of slip,am I in the ball park or way off?
May try some 24's and see how they work out.
Any ideas on the vibrations I mentioned? Were the props possibly try to act as brakes and that caused the shuddering?
Thanks
Steve

Steve,
That's a really big jump in pitch(especially since it was from 3-blade to 4-blade) and you're nowhere near the recommended WOT rpm range for those 500's...They sound overburdened with those props and 1.36 gears.

Like Cobra mentioned, the 24P B1's lab-finished would be the ticket.

Nick
When I was told that the 26's would be the ticket for the way my boat was set up,I thought it was a BIG jump too.But the person that recomended them has way more experience than myself,but he also said that I would need to have them labbed and spin them in instead of out,which I haven't tried yet.
Any ideas on the severe vibration when quickly coming off plane???
Steve