Still not happy with my LT. Have a beavertail with a modded gx390; stage 3 kit from NR Racing and loop exhaust.

Considering going up to a predator 22hp but not sure how much improvement I will get. The stock twin should be a lot quieter but that would only be an added benefit if I got more performance.

Seems to be very mixed reviews on power/torque differences between singles and twins.

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Twins have more torque and power hands down. The predator 670 is a huge value. If you have a true flat bottom 16ft you can expect in the range of 17-20. If you have a mod v like me you will get 15 with a 9x5 prop

It's simple. get a mud motor. shoot ducks in the face.

It's a war eagle 236 (mod V) with BT pods. 4'8" beam, hull is 200 lbs empty, prob 300 with pods, lights, grab bar, all he extras that don't come off.

Started with a 9x5 and it was too much, I couldn't get any RPM with the prop fully submerged. Swapped to an 8x6 and now it runs like it should, I can acctually "float" the handle with little effort while driving if my load is balanced correctly.

If I am running empty and alone I can touch 17mph. As soon as I add any kind of load I'm down to about 12mph and fully loaded with blind, 2 guys and a dog etc it's prob down in the single digits.

Im not looking for a racecar out of a longtail but I would like to have a boat that did 15-17 with a load when I leave to hunt with a passenger. It's a great little boat when it's just me and the mutt but I would like to make it enjoyable for 2 hunters.

Admittedly I am prob trying to do alot to compensate for having bought too small of a boat to begin with, but unfortunately I am closing on a house in about 30 days so the option to upgrade my rig this year is non-existant.


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I'm in the same situation except running a 15-42 rivet boat.. Same motor stage 1, getting about 13-14 with just me add a person and it goes way down- stock 8x4.
I was looking at a 9x5 prop but I don't know if it will get enough rpms. I was wondering also about throwing on a predator 22hp vtwin and if it would be worth the money.

I have 33 hours on my Predator powered Backwater. 4100 RPMS in the water all day with a 9x6, 19-20mph 2 men and light gear. Same load with a 9x7 got me about 4k RPMS and 21/22mph. 23 solo. Been a good motor.

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Yep, the 670. My motor/rigged boat weights in around 550. 2 man hunt just under 1,000 I imagine.

Just wanted to update for anyone else searching this swap.

Unfortunately I was no longer able to apply a 20% off coupon at any of my local stores so I picked up the predator 22hp for 699 + tax.

Be sure to budget for additional parts needed. I needed/bought; gas tank, fuel line, electric pump, fuel filter, hardline tach, tank hold down and sprayless disconnect. I already had a 9x5 prop so I put that back on.

Swap was almost flawless. The only thing I had to modify was drilling a new hole for the throttle cable linkage lower on the bracket so that my MSR clutch lever would give me full throw and run up to 3600 rpm. Also swapped the factory fuel filter for a universal with a larger inlet nipple to match the fuel line- the original was too small and the line would leak around the nipple.

New setup planed the boat at 20-21mph at 3600rpm on my first run but the real bonus was that it ran 13-14mph at 3550rpm with a full load (approx 600lbs); 2 men, dog, 3 doz decoys etc. My old single couldnt break into double digits loaded and it plowed water. The quiet factory exhaust is a nice addition compared to my old modified single with a loop pipe.

The additonal weight I was originally worried about was not noticeable.

All in all, I would 100% recommend swapping to the predator over modding a single. It got me what I wanted and probably the best performance I can get from a longtail on that hull. No plans for mods, will run this setup until I can upgrade to a larger hull with a SD.

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Cut and open up the sheet metal under the air filter. If you have the ability, pull the carb / intake and work all the rough areas and casting marks out. Adjust the governor and you should be able to get more RPMS out of it. The 3550 is likely still bouncing the governor.

The predator I built is well over 100 hours now. The only problem it has developed is with the starter not fully engaging. Going to try swapping to a Honda starter soon.

Yeah, power to weight v-twin is really the best deal going.

Numbers on a calculator don't always translate to real world performance. Ask NASA and the lost probes they had the numbers correct on. Or test pilots who lost their lives even though the numbers were correct.

Yeah, maybe nasa gets its wrong all the time, but these things don't defy physics, and this is NOT rocket science. 20-21 at 3600 rpms isn't realistic with a 5 pitch prop at 3600 rpms.

Must be a 5x9 prop.

I hit those numbers with the same engine. Except I ran a 9x7

i've made the mistake of having my gps app on KMH and was like, "yeah my gx390 long tail does 18!!"