PARADOX

If this needs to be moved to ? OK.
What is a realistic and acceptable prop slip % on a non racing boat. Lower the better, I got it, 0 is theoretical.

bajaman

8% to 10% is about the best I've seen reported.

Griff

Its depends on the hull. Most V bottoms will be 10-20%

blownhammer2000

iTrader: (1)

I've always realistically been in the low teens to near 12%

tmmii

I think it’s just one of the many variables but lower might not be better. One of my old boats was faster with a different prop and more slip than the prop with lower slip.

Twin O/B Sonic

10% has always been my target and best Ive ever gotten.
And ain’t easy!

Mostly twin OB Vee’s.

My first twin OB 24’ Sonic was down to 8%, a point where most prop guys said they couldn’t improve on, but consider…..,if your tach is reading 1-2% low, your actual pitch is more than stamped on the hub, your Speedo/GPS is off by 1-2% etc…..

I have seen all the above.

Some of my friends in light, fast, single OB tunnel boats are claiming 3% and less w/the new $5K CNC built wheels!

A prop calculator is great fun to play with, very educational, and makes a great lie detector for those w/amazingly fast boats 😉

PARADOX

Thanks
I run between 10 and 13, depends what prop I use, and load. (took a while to dial in ) I actually want to talk a friend getting a higher pitch prop. 38'. relatively light boat. 600+ HP, his running 85-86 MPH at 5800+ RPM's with 28's
I want him to go to labbed 30's.

P

F-2 Speedy

iTrader: (6)

I might have a pair for sale after testing the new ones........

jadento

I was thinking about this the other day after a friend of mine had his props reworked. He was running stock 26 Pitch Bravo1s on a 35 fountain with 496HOs. All standard fountain setup. We have recently installed new 496 long blocks(long story) and speed came back closer to where it had been the whole boats life. But was off a few MPH even though we were touching the limiter. So decided to have the props cleaned up(not labed). Just straightened out etc. The shop got ahold of him and reported back the props are nowhere near the advertised 26 inch pitch. More like 24.5 average. Which over the years I have heard Bravo1s run smaller than advertised? Anyhow, he had the shop add an inch of pitch bringing them to 25.5ish average. We gained 4 mph. (from 71 to 75mph). So if we use the advertised numbers. 26 pitch props, 1.5 ratio, 5100/5150rpms, speed 71(gps). That is 15-16% slip. Using the true pitch reported by prop shop brings that number down to 11. With the props back and getting 75 puts slip at 10%. Lots of variables. But those are real world experiences in the past few weeks. BTW, he tried my stock 28 Bravos while his were in the shop...71 MPH was all he could turn them to. But I don't know the RPM as I wasn't with him. On my boat 71mph is about 48-4900. So with advertised pitch puts it at around 17%. Who knows, Id say the take away is if you really want an accurate value, you need to have your props measured, check your tachs accuracy etc.

Griff

Bravo 1 props are always at least 1/2-1" light on the stamped pitch.