49.9 MPH @ 4100 rpm.

[RCSConstruction]

Hope everyone had a great fathers day weekend.
Finally did some boating and ran a wot run on a some glassy water.
GPS read was 49.9, tach said 4000-4100, did a little trimming but not much. (ran outa room)
I know the motor had more left in her.
Stiletto bayrunner 22p 4 blade out the back of a 2000 wellcraft 186ss volvo penta 5.7/sx drive. (Motor has 12 hours on her now)
Very responsive down low, I towed 4 people in my new tube and had no problems getting up on plane at around 1900rpm, which comes on very quickly I might add.
Cruising speed of 35mph at around 3000 rpm per GPS.
Have an edlelbrock 600cfm 4bbl marine carb to replace the 2 bbl holley and also a MSD marine ignition box.
Think those two will put me where I want to be?
Thanks for any input.

P.S. The drive ratio is 1.60.

 

[Tail_Gunner]

Re: 49.9 MPH @ 4100 rpm.

That's a 6% slip so far now taking those same number's and going to 4900 rpm get ya 60 mph......grow some nard's and pop her wide open, trim her till she starts cavitating back off a bit and hold on.........


http://www.go-fast.com/Prop_Slip_Calculator.htm

 

[RCSConstruction]

Re: 49.9 MPH @ 4100 rpm.

That's a 6% slip so far now taking those same number's and going to 4900 rpm get ya 60 mph......grow some nard's and pop her wide open, trim her till she starts cavitating back off a bit and hold on.........


http://www.go-fast.com/Prop_Slip_Calculator.htm

I can't spin her to 4900. It was at 4000-4100 for around 10 seconds till I backed off. Wouldn't budge. I trimmed up at around 3800rpm and that's what got me to 4100.
I am throwing the 4bbl on tomorrow.
BTW, The smart tabs really gave the boat a solid driving experience. I am going to spend some time fine tuning them and this thing will handle like a sports car.

 

[jimmbo]

Re: 49.9 MPH @ 4100 rpm.

The 4bbl should give you about 250 - 300 rpms more, Well that's what I got when I put a Holley 650 speadbore on my Volvo 5.7 litre, but mine had a 1:1.51 ratio in the gearcase.

 

[Tail_Gunner]

Re: 49.9 MPH @ 4100 rpm.

I can't spin her to 4900. It was at 4000-4100 for around 10 seconds till I backed off. Wouldn't budge. I trimmed up at around 3800rpm and that's what got me to 4100.
I am throwing the 4bbl on tomorrow.
BTW, The smart tabs really gave the boat a solid driving experience. I am going to spend some time fine tuning them and this thing will handle like a sports car.

You might want to see Bond-o on the carb, if i remeber yoiur setup for 300 hp dunno if a 600 will do the job