WOT speed

minnesota

Hi all
Anyone running Rinker 280 with the 8.1 Merc (496) and 24p props. Can you advise
1) What is your top speed at wot
2) What is your WOT
3) What is your best economical cruising speed?
thanks

zaverin1

Running twin 4.3 alphas with ss props
top is like 45 lol

Cableguy Greg

My 280EC has the 6.2 and I get 41MPH GPS WOT. I am at 4980 RPM at WOT. You should have better speeds and a lower WOT.

minnesota

Cable guy, mine does only 38mph at 4200 wot. WOT wont increase even when I down pitch the props. hmmm

Cableguy Greg

My props are 22 pitch. If you go down in pitch, you should have better hole shot and less top end. Higher pitch will sacrifice hole shot for a better top end speed.

Cableguy Greg

@jbschmalz23, what did you get on your 280 with the 496?

junebug

I have the Volvo 8.1 with DP and yesterday we were out with 4 adults full of fuel and full of water.  We hit 43.5 on GPS WOT cruises nice at 3500rpm 31mph GPS

Handymans342

junebug said:

I have the Volvo 8.1 with DP and yesterday we were out with 4 adults full of fuel and full of water.  We hit 43.5 on GPS WOT cruises nice at 3500rpm 31mph GPS

Wow. That has to be 40 GPH at wot

jbschmalz23

Mine should be about 45mph WOT, but never took it there. Lol. On the 496, WOT should be around 4200-4500 rpm. When I cruise, I'm usually at 3500 rpm and about 27mph which is getting me 16-17 gal/hr. The VV7 makes it nice to find that sweet spot. I have to 22p prop as well. 

minnesota

I run 24 pitch and will max out at 4200-4300 rpm at only about 38mph.  My best cruise is about 30 mph at 3400 or so.  I am concern that WOT is only at 4200, even when I went to 21p,  the WOT is still at 4200 and top speed drops to 35mph.  Junebug,  I like the 43.5 mph. Doesnt mean I am a speed freak, but I've always felt my boat isn't doing what its capable of doing. Hope nothing is wrong with the motor.

jbschmalz23

That 496 is a workhorse. Should be plenty of power for the boat. How many people are on board etc when you are trying this? 

junebug

Minnesota I'm definitely no speed freak either lol.  I was interested to see what wide open throttle was.  I only had it there for about 30 seconds.  We cruise all day around 3500rpm. I am pretty sure I have the F5 props. 

rasbury

I have 22P props I believe- my cruising speed where everything feels real good is around 27 on GPS- not sure where it is on the tach as it bounces all over the place!

JasonA

I have a 290 with a Merc 8.2 and 24P props. Boat is still new to me but at WOT 39MPH at 4200RPM. According to VV best cruise is around 34MPH at 3800RPM burning 22GPH.  I am in the same 'boat' as you and feel the boat is down on power and RPM. VV threw off a 'Service Catalyst System' the last time I was out and the mechanic is coming tomorrow to take a look. I am willing to bet I have a clogged CAT based on the symptoms.

minnesota

JasonA  sounds like we have the same set up, speeds and "symptoms?" Please let me know what the mech finds.

summerx

I will ask it only because I didn't see it mentioned, but did you trim the outdrive up once on plane?  that can easily make a 3-5 mph difference.
I would also expect you to be able to get above 4200rpm with that engine.

Michael T

With my two cruisers 2013 EC 310 and 2014 EC 360 the initial engine run-ups were both supervised by the area Mercruiser representative - as part of the Axius "personality" adjustments.

He made it clear that the engines had to run in their RPM range or something would be very wrong and the engines would suffer - we all know this.

On both boats the engines ran right near the top of their WOT.

If you are running outside of your engines specified WOT range, IMO - you have a problem: boat over weighted, some underwater obstruction (barnacles/swim platform drag), your props are wrong, your boat is improperly trimmed, your clutch and/or coupler is slipping.....or......the boat may be underpowered.

I laugh when I see a 350/360 Rinker with twin 350 Magnums. Whoever allowed that should be shot. To find one go to the Yacht sales. When you see a real low price for a 350/360 look at the powering. I bet it has twin 350s or 377s ....dumb, bumb, dumb!

When I see 350/ 360 with 377 I don't laugh but I do cringe as that too is IMO waaay underpowered. A friend had one and hated it (I have written about this before).

Properly mated with power, Rinkers will accelerate and handle like high performance boats. Example Rinker EC 310 with twin 350 mags - superb! Rinkec EC 350/360 with 496s - excellent! Rinker Ec 360/370 with 502 Mags - unbelievable!

I have read so many sad cases on this forum over the years of underpowered boats and the grief they cause....and where an owner has stepped -up in a repower and found new joy.

If you are getting a deal that seems to be too good on a boat look at its powering. Find the same boat that is more expensive - I bet it has bigger engines.

For enjoyment AND re-sale stay away from underpowered boats.

BTW - Don't blame Rinker for sending underpowered boats out of the factory. A number of dealers - one in particular, in the U.S. - is a real, IMO,  AH - who brings in low priced Rinker cruisers with engines that are, IMO, ridiculously underpowered.

My dealer and a nearby one in Quebec (Marina Port Lewis) were well known for recommending the biggest engines to potential Rinker customers and only spec ordering Rinkers with the most powerful engine packages.

minnesota

Summerx,  my boat is on plane at about 23mph. I only run my boat on plane.

JasonA

minnesota, my mechanic found four codes on my engine:

Misfire
O2 sensor Failure
Crankshaft Position Sensor Failure
ECM Fault

His initial conclusion was that the ECM could be bad. If the CPS was bad the boat would not even start and it does start and run. I talked to Whipple about the PCM and reprogramming it for a stage 1 tune and dropping the CATs and rear O2's. They doubt the ECM is bad so I am going to try that first to see if it resolves the problem since it will kill quite a few of the possible culprits and give me another 50HP.

aero3113

Another 50HP?! Are you sure,that's a great upgrade if that true!

JasonA

The tune will basically turn a 8.2 MAG to an H/O. They have a stage 2 but it require 91 octane which is hard to find on the water around here.

https://speedonthewater.com/new-boats-engines/1638-whipple-offers-pcm-upgrades-for-mercury-8-2-engines

https://whipplesuperchargers.com/index.php?dispatch=products.view&product_id=54

minnesota

You are lucky to be running with a bad crankshaft position  sensor.  First I will read my ODB codes for sure. Thanks

skennelly

465hp for mag 350...that sounds interesting

minnesota

I replaced all my plugs, WOT went up to 4450 and gas mileage went up to 1.8m/gallon at best cruise. Who would have thought just by changing spark plugs.

jmichels

**** were they that bad?any pics?

minnesota

They all look very good actually, except one with some oil residue.

jmichels

hmm interesting. 

JasonA

For anyone curious my WOT issue was due to fuel pumps. I had both the low and high pressure pumps replaced. The surging is gone and WOT is 4400 RPM now prior it was having a hard time hitting 4000RPM. Misfires are gone now as well.

minnesota

interesting

F1100

1993 300 FIESTA VEE, TWIN 5.7L CARBED

WOT FULL FUEL 34MPH
WOT EMPTY FUEL 38MPH
PER GPS