1652 Weld-Craft side console W/transom pods for a total length of 17'-11" and 6' width. 2020 Zuke DF60A W/Stainless 3 blade Power Tech 15" prop. Zuke operating range is 5,300-6,300 RPM. Currently getting 10.5-11.5 MPG @ 20-24MPH cruise @ 3,900-4,300 RPM. Top speed is 34 MPH @ 5,400 RPM, 900 RPM lower than Max RPM. This is at 3/4 throttle, the last 1/4 of throttle (around 2.5" of throttle range) does not increase RPM. This tells me I need to reduce pitch to at least a 14" to optimize RPM range. I'm not looking for more top speed, 30MPH is plenty fast enough in a jon boat. I'm looking for better MPG @ cruise. I know with a lower pitch my RPM will increase a little @ cruise speed but in theory I think matching the prop better to the engine will increase efficiency and help overall MPG. Anyone agree of not? Am I chasing my tail and just leave it as is? Thoughts?

I'm of the "I can't have enough spare props club", so try the lower pitch prop to get the motor working proper.

If it doesn't perform well, toss it in the bilge for a spare when out and about.

As of now you make be working the motor to hard because of pitch

I never heard of using MPG for boats, it usually was gallons per hour.

How much weight in the boat and are you trimming it right?

Thanks Guys, boat is rated for 60HP, 4 Peeps, 950Lbs without the buoyancy of the pretty substantial transom pods.

Weights. Bare hull 600lbs, Engine/prop 240lbs, 13 Gal Aluminum tank at transom full 115 lbs, Group 31 and group 24 East Pen AGM's up front under casting platform with trolling motor 180lbs, Me 225 DW 118, Misc safety gear, fowl weather gear, Qbeam, tools, PFD's and cooler 100lbs. So around 850lbs total load out.

Trim? I always trim up to just before it starts to porpoise. The 18" long and 16" wide transom pods really shine here acting like the mother of all trim tabs. I can get half the boat out of the water at cruise and 2/3eds out around 30 MPH. Boat performs great. I shopped for 5 months to find a deal on a Jon with pods because the last section of my private ramp is pretty steep at low water and I would get water over the transom when launching my Pro-Line. Not a problem with Pods and now that I have experienced the trim benefits I would not own a jon without them. Being able to trim way up and run without all the additional wetted hull resistance really helps with efficiency/fuel mileage/performance.

Tech I spoke to this morning at Power Tech said it was an impossibility for my engine with 2:70 gear ratio and the 15" prop to run 34MPH at 5,400. Tech said even with a impossibly low 1% slip to go 34MPH the engine is turning a minimum of 5,750RPM. Conclusion, som ting wong with one year old factory Zuke Tach.

May snag a tiny tach to confirm or just run it as is.

Just try dropping 1-2 pitches.  Cabela's takes props back.  

Just saw.....15 is way too much.  Drop a minimum 3 pitches, but don't over - rev.

Farina tach made for Suzuki. Known issues. There is a mathematical formula using the hertz output on a meter to establish true RPM from the ignition circuit. I'd only have to make up a few female to duplex male jumpers to do it. Not great boating weather right now. Working on it.

DW and I did the 19 Mi loop around our lake yesterday. 21MPH cruise is now an indicated 3.6K RPM on the tach, It used to be an indicated 3.9K RPM. Tach is obviously defective, and just out of warranty. The can of worms is it has the hour meter for the engine that it displays total hours in RPM's and displays alerts for service intervals when the key is activated. Can a Suzuki dealer program a new tach to my existing hours so my hours and service alerts/prompts are correct?

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I always buy the manufacturers gauges.
Never had good luck with aftermarket.

It is the Suzuki branded tach from the dealer. Frina makes some of their instruments.

Good news is the hours and service prompts are in the ECU and will work with a new Suzuki tach.