Another " how fast " discussion - Page 2

draglink · #11 05-13-2012, 07:01 PM

Quote:

Originally Posted by tartuffe

I have a 200 Rude on the back and can only get around 38 MPH at WOT but mind you when I punch it I come straight out of the water like a trident missle.

But yeah, I gots issues, prop issues. Plan to rectify that this year.

I have the opposite issue....what prop are you running?

bgreene · #12 05-13-2012, 07:42 PM

Quote:

Originally Posted by tartuffe

I have a 200 Rude on the back and can only get around 38 MPH at WOT but mind you when I punch it I come straight out of the water like a trident missle.

But yeah, I gots issues, prop issues. Plan to rectify that this year.

Assuming the engine's got proper compression, i figure you should run at least 45mph when you get it sorted out.

tartuffe · #13 05-13-2012, 07:48 PM

Its a 14.5x17, I believe I'm going to a 14.5x19 hoping that will bring my RPM down (around 6300 trimmed out) and increase my miles per gallon. Right now I average around 2.3 mpg when I run offshore.

THEFERMANATOR · #14 05-13-2012, 08:03 PM

Quote:

Originally Posted by tartuffe

Its a 14.5x17, I believe I'm going to a 14.5x19 hoping that will bring my RPM down (around 6300 trimmed out) and increase my miles per gallon. Right now I average around 2.3 mpg when I run offshore.

Either your prop is toast, or your tach is way off. A 17 pitch should have you running in the 50's at 6300RPM's. I spun a 15.5" X 17 on my old HYDRA-SPORTS at 5600 which took me up to 53MPH.

draglink · #15 05-13-2012, 08:12 PM

Quote:

Originally Posted by tartuffe

Its a 14.5x17, I believe I'm going to a 14.5x19 hoping that will bring my RPM down (around 6300 trimmed out) and increase my miles per gallon. Right now I average around 2.3 mpg when I run offshore.

Im 50+ at around 56-5700, BUT I feel like I need to get more bow out of the water....I can trim her till she cavitates and still need more lift

tartuffe · #16 05-13-2012, 08:16 PM

Quote:

Originally Posted by THEFERMANATOR

Either your prop is toast, or your tach is way off. A 17 pitch should have you running in the 50's at 6300RPM's. I spun a 15.5" X 17 on my old HYDRA-SPORTS at 5600 which took me up to 53MPH.

I really wish I knew, I bought the engine last year, just rebuilt after my 225 rude shredded the splines in the crankshaft. That setup also only ran around 38 with just myself on a glassy day. I agree I should at least be in the mid 40's. Two GPS's told the same story, pig.

Its gotta be the prop and the prop is in good shape stainless, no dings or chips. Maybe not the pitch but the diameter. I wish I could rent a prop to get the right combination of diameter and pitch.

I gotta say it is nice being able to stand her up in 3-5's in the inlet with a low wave period.

tartuffe · #17 05-13-2012, 08:20 PM

What prop do you have draglink?

draglink · #18 05-13-2012, 08:56 PM

Quote:

Originally Posted by tartuffe

What prop do you have draglink?

14 1/4 x 19 SS, ive tried a few different props but always come back to this one

bgreene · #19 05-15-2012, 08:30 AM

Quote:

Originally Posted by tartuffe

I really wish I knew, I bought the engine last year, just rebuilt after my 225 rude shredded the splines in the crankshaft. That setup also only ran around 38 with just myself on a glassy day. I agree I should at least be in the mid 40's. Two GPS's told the same story, pig.

Its gotta be the prop and the prop is in good shape stainless, no dings or chips. Maybe not the pitch but the diameter. I wish I could rent a prop to get the right combination of diameter and pitch.

I gotta say it is nice being able to stand her up in 3-5's in the inlet with a low wave period.

Yup, with 225 hp in proper running order, and assuming your boat's same - not carrying an extra 1,000lbs water etc..............you should run over 50mph. The various 150hp's push the V21 to 39-42 mph. I get a little over 40 with mine.

Shrek · #20 05-18-2012, 04:58 PM

FWIW, my V-20cc with a 1999 Merc 225 Saltwater series (carbed motor) with jackplate did 53 mph wide open with 60 gallons of fuel and me. You should have seen the look on the doofus on the jet ski when I passed him ... priceless.

I was turning a 15 1/4 x 19p 3 blade stainless no name prop @ 5600 rpm. Had just a touch of trim tab, motor trimmed out and at max elevation on jackplate. Oh yeah, I also had the bimini up and there was a bit of a breeze and a very light chop. The prop was kind of blown out. My guess is that there was another 2-3 mph with a better prop.

My understanding is that the Opti is actually more stout than my carbed motor. I'm looking for a late model (07 or later) 250 opti for the back of the Short Bus. She should scream with that and I should see a doubling of my mileage. I hope so because 2mpg sucks (fuel).