Classic SeaCraft Community - Suzuki 250 4 stroke

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Re: Suzuki 250 4 stroke

Quote:

With the motor hitting the Rev limiter there is room for some more pitch to be added. It may slow the boat out of the hole by 1 or 2 secound's, but so what. It should increase the top end speed and lower the cruising RPM to get even better fuel millage.

Quote:

Chuck - I'll keep my eyes peeled for a Rev4 19 or 21. You know you want to tweak that boat.

Peer Pressure. :rolleyes:

strick

Re: Suzuki 250 4 stroke

HeHe Think $ in fuel savings. :D

Re: Suzuki 250 4 stroke

I don't know at what RPM you hit the limiter, but if you just barely hit it occasionally, then with the motors at a cruising RPM/speed, they won't be working as hard as if they were propped for a max of say 5K RPMs.(It's also nice to plane easily).

However, if your max RPM loaded is more than 200 RPM above the top of the recomended max RPM range, plan to change props. 1 inch pitch increase with the same style propos equals an aproximate 200 RPM drop in most cases.

I'm old school - I believe your max RPM at max weight should be the upper end of the max recommended RPM range. It's the old Mad Max theory. "Max at Max should be Max."

If you ever take on any water, and need to run to shore, or get up and drain your boat, having the available applied torque to plane with an extra ton of water in the boat is a VERY nice thing to have.

My previous Seafari was a '77 with a 225 Merc on the back. I once had had a fish snag a wire leader on my snap-in drain plug and thus remove it while 20 miles offshore which taught me about having extra power on tap. I couldn't find a spare plug in the boat when that happened, so all I could do when the water was above the cockpit sole was put it in gear and get going to drain it, and not stop until I ran it up onto the forks of the marine forklift back at the marina.

My advice? Keep it slightly underpropped.

Re: Suzuki 250 4 stroke

I agree with you 100% Fr. Frank. Having witnessed the power of that motor . . . I still believe there's some room for tweak'in, but it's one sweet ride.

Re: Suzuki 250 4 stroke

Well somehow I thought 1 knot = 1.2mph . . . I learned today that I was wrong and 1 knot =1.15mph . . . so here's the updated numbers

Sorry Chuck . . .

4000rpm 24 knts 27.60 mph 9.5 gph 2.91 mpg
4500rpm 28.5knts 32.78 mph 11.0 gph 2.98 mpg
5000rpm 33 knts 37.95 mph 16.0 gph 2.37 mpg
5500rpm 36 knts 41.40 mph 19.5 gph 2.12 mpg
6000rpm 39 knts 44.85 mph 22.5 gph 1.99 mpg

Re: Suzuki 250 4 stroke

well, 30mph at 6gph still comes out to 5 miles per gallon right? :D

Texaco hates me!