Lab /labbed prop or Stock? Bravo
 

I'm running a 30" bravo now, non-labbed, have not had the chance to borrow someones labbed prop (no body in my area has one)

Gear ratio 1.5, RPM 5,100, top speed 86 MPH, slip 11%

With the 28 non-labbed, 5,500 RPM (as per tach, which is above the redline for a 500 HP) 84 MPH slip 13%

Midrange is MUCH faster with the 30.

What difference would I notice with a labbed 30"?

Basically you can spin a labbed 32 the same as you can a non labbed 30, pick up mph, stay the same rpm's

John jr

I would lab 300 rpm on the 30s to get you spinning them 5400 and you will pick up top end.

Any downside to the Labbed prop? (besides cost)

What is done to the prop to lab it?

(my understanding, thinner blades and better balanced)


Between the 28 & the 30, the one big difference was top end power, the 28 gets to the top quick, the 30...takes a while. Not a big deal, but thought I would mention that.

This is the biggest heaviest boat I've ever owned, so I'm used to, instant accelaration, delay feels odd to me. But have been a passenger in boats up to 42' with twin 1500's, and even with that power it takes a while to get up to speed

Labbed props are not as durable. I have thrown blades on two of them in the past three seasons. Of course I am surfacing them but thinning the blades certainly doesnt make them stronger. Any debris can damage them and lead to a crack.

Your midrange could suffer with a lab job as well.

As Philm stated, I remember reading somewhere before that you lose a little midrange efficiency with a labbed prop. Don't know if that is fact though. I would ask Brett at BBlades.

I would say it depends on what you do with it. Also when labbing, you could choose not to thin the blades as much as possible. If you half the thickness of the blade, you are left with about 10-15% of the original strength.

A true lab job is a custom prop suited for what you want and need. Find a good shop like Bblades or DAH ect. and work with them. Thick or thin blades, mid or top end, lift/no lift ect. ect. ect.