Is there that much of a difference between the 2 ? I'm looking to put a 4blade on my evinrude 150. Don't know to much about props and wanted to make sure I wasn't wasting money?

I think the 4 blade has a tendency to grab more water as a result of the extra blade. As a result I think provides more stability in heavy seas or rough water. As far as speed performance I don't know about that and it may vary depending on each individual setup.

From my understanding, it really depends on how the specific boat likes to ride. I've heard in some cases a 3 blade is "faster", but in other cases I've heard a 4 blade can push just as fast but handle better.
I swear matching the right boat and prop is an art.

3 blade is faster, 4 blade gives you a better hole shot.

+1

Why do all the Bullet guys run 4 blades?

I was told the 4 blade gives you a better hole shot but it lowers top speed. I have a 3 blade for my Tracker that has never been in the water but I am too good at finding boulders or at least my prop and lower unit finds them easy enough to run an aluminum prop. My 1st Tracker came with an aluminum prop and I was constantly nailing rocks,stumps and subsurface floating timber that assured the local prop shop my business

My guess is they need the handling advantage.

I would also guess a 4 blade would be better on a boat that is a little under powered. How big of a boat is your 150 on?

Boat dependant, some boats will run faster with a 4 blade. The bravo is very popular with the go real fast guys(bullet,allison).
rule of thumb though is usually what has been stated above. Squeezing all your speed out of your boat will involve alot of trail and error with props and set-ups with each one tried.

Where�s the love for 5 bladed props?


TFP

Because a 4 blade is easy to drive. 3 blade is faster.

I would post this question in the General Equipment forum to get Steve's answer. Steve has Steve's Custom Props and he is the best I know of as far as props.

Might also try pm'ing him at steve@scp or his website is: http://www.stevescustomprops.com/ .

I ran a 3 blade and a 4 blade on my Bullet. Not a significant change in speed at all, but the 4 blade was a better handling prop. I have an Allison now and have never run anything other than a 4 blade. With the advanced designs of the current 4 blade props, you are really not compromising anything.

this is an excellent statement!!!

todays propeller technology is so advanced that with 4 blades you don't loose any speeds and in most cases you'll gain speed. depending on your hull and setup.
the blades can be more effecient too.

fast guys run 4 blades for several reasons.
1 is handling is improved.
2 is safety.. if or when a blade breaks because we run the motor so high.. you'll still have 3 blades grabbing water so it will hold the boat.
3 the 4 blades look kewl
4 todays engine make so much torque that the 3 blades (choppers) will blow out severley on holeshot where as a 4 blade won't

that's in a nutshell and hope it helps.