90 ETEC on a Potter 20 CC???

[rockdoc]

Great thread guys, I really appreciate all the experience and info. I'm looking at hanging an outboard on my previously i/o 74 seafari, and have been seriously considering a Suzuki 90.

Steve

[Fr. Frank]

Don't let Terry scare you off of going out to the Middle Grounds! It is literally the best grouper fishing in the entire Gulf of Mexico! (Lots of Goliath Grouper/Jewfish though, which you can't keep, even though I remember them as VERY tasty).

I ran my 1972 20' Seafari out to the Florida Middle Grounds from Cedar Key (210 miles round-trip) in front of three different motors: twice with a '77 120 hp Chrysler, once with a '91 XR4 150 Mercury, and finally, twice with an '06 90 Mercury Optimax. I never had a problem mechanically, but I did always take kicker motor.

Like Denny, I never made a 100+ mile trip like that alone, but always in the company of other boats, usually with a larger (40+) Cruiser for a floating "hotel" while we were out there. Let's face it, 105 miles at 20-25 mph is a LOOONG ride. (I do confess to making the crossing to the Bahamas alone many, many times, though, in a variety of boats.)

With my 120 Chrysler, I got about 3.7-3.9 mpg average at 22-23 mph.
With my 150 Mercury, I got about 2.9-3.0 mpg at 25-26 mph, and
with my 2006 20" 375lb 90hp Optimax, I got 5.7 mpg at about 25 mph.

The 90 Etec I now believe to be a better choice than the Optimax, mostly because of the weight and much better reliability. Fuel economy is reportedly now as good or better, too. I have a parishioner with a new 2013 90 Etec on a 1700 lb Key West 186, and he insists he is averaging over 6.5 mpg here in Choctawhatchee bay. It's so quiet, that when we're fishing together I have to look back to see if the motor is running at idle, if the stereo is on.

I also agree that you should raise the transom to 25" if you haven't already, and forgo the bracket. CG is very important in Moesly hulls.

[Slo Poke1]

I've seen some intriguing performance discussion around here for the Etec 90 on a 20 footer. Also, added performance discussion regarding brackets. Which would have a greater impact on performance with the Etec 90 on a 20': a bracket or hydraulic jack plate? If one went with a 14" jack plate, would that forego the need for the added performance from the bracket?

[McGillicuddy]

Originally Posted by Slo Poke1

I've seen some intriguing performance discussion around here for the Etec 90 on a 20 footer. Also, added performance discussion regarding brackets. Which would have a greater impact on performance with the Etec 90 on a 20': a bracket or hydraulic jack plate? If one went with a 14" jack plate, would that forego the need for the added performance from the bracket?

I'd opt for hanging a E-tec 90 on the transom. The beauty of the 90 is its weight to power ratio. Its the closest thing to the weight of the early 115 2-strokes, with nearly equivalent power, and 2-3x the fuel efficiency.

Only my opinion, but I wouldn't trade the possibility of a 2-3 mph gain on the top end for the balance and handling the transom mount would offer.

[72potter20]

How severe would the trade off be? The bracket with swim platform is a must for me, also considering a 90hp etec or suzuki for the most fuel efficient setup. Looking at a 24" setback

[McGillicuddy]

I think the main trade off is simply in re-balancing the boat in any of the traditional ways. Slide the console forward a bit, move batteries or fuel tank forward or add ballast forward. Or better yet, get a couple of babes to ride with you and place them where you need them. Might be as simple as having 2 riders for of the console.

I don't think it would be nearly as dramatic as if you were moving the additional 100lbs of a 150 hp motor 2' aft, but some re-balancing would be in order.

[beastley]

Great thread guys. I'm still scratching my head. I have a 20' Overnighter with a hermco bracket installed. The liner on my boat is the same a the seafari with a different cap. I've enclosed the transom, moved batteries forward of the fuel tank and replaced the 47 gal tank with a shorter 35 gal tank. The 150's seem like overkill but I also don't want to be underpowered. I'm getting close to the point of buying a motor but can't decide which way to go.

To be honest I've never had this boat in the water, so I have no experience with its performance. Any input would certainly help.

[Terry England]

20' Low-rider Safari (Overnighter) with Hermco Bracket -
Recommendation #1 - Get the 25" 115hp E-tec. They make 129 hp at the output shaft and use a 150 hp lower unit with 2.25 to 1 gears. They are the smallest engine you can get the I-Command gauges with and study everything you could possibly want to know. You'll need to by a couple of gallons of oil a year and need to add about $1.25 - $1.50 per hour of running time for the three year
service interval. I think you may "touch" 35 MPH with a 15 X 17" wheel and will not use more than 25 gallons per day running daylight to dark.

Recommendation #2 - Find a good Salt Water Series 130 Yamaha, Suzuki DF-140, V-4 130/140 hp Carb. OMC, or an older 150 hp 2 two stroke carb Merc., bolt it up and let it eat. Do you know how much gas you can buy for the possible 1 to 1.5 MPG you might gain for $6,000.00? You could run the Great Circle Route twice before you made up the difference!

[Bushwacker]

Originally Posted by Slo Poke1

I've seen some intriguing performance discussion around here for the Etec 90 on a 20 footer. Also, added performance discussion regarding brackets. Which would have a greater impact on performance with the Etec 90 on a 20': a bracket or hydraulic jack plate? If one went with a 14" jack plate, would that forego the need for the added performance from the bracket?

The "added performance from a bracket" claim is misleading. The reason you might pick up 2-3 mph in WOT speed with a bracket is that it shift's the CG aft by about whatever the setback is. That makes it easier to get the bow up to reduce wetted surface and drag in flat water. What the bracket makers DON'T tell you is that, UNLESS you rebalance the boat by moving gas tank, batteries and console forward enough to eliminate the CG shift, adding a bracket will significantly increase your min planing speed and hurt the ride!

Although I added a galley seat to my Seafari that added a little weight forward of the CG, I couldn't move the gas tank and of course there is no console to move. With the old 300 lb motor on the transom, I could easily plane at 12 mph. Initial trials with a new 429 lb motor set back 30" on a bracket, my min planing speed was up around 22-23 mph, which is absolutely unacceptable! After adding a stern lifting 4B prop and a Doelfin, I can again plane at 12 mph, but I'm sure those 2 items COST me more WOT speed than I gained with the bracket! A good friend of mine with the same boat just repowered with the same motor but no bracket, and he's at least 5-6 mph faster @ WOT! I don't really mind because I never run WOT, the boat rides great, still averages over 4.0 mpg, and I like the extra room and big swim platform. But if you're thinking of adding a bracket just for another 2-3 mph top speed, just recognize that there is a risk of losing more than you gain if you screw up the boat's balance! And a jack plate can still cause the problematic CG shift, but without providing the benefits of a swim platform and a big flotation tank to maintain static trim for self bailing at the dock!

Bottom line is that adding a bracket on a 20 is not as simple as it looks and requires some serious thought and modifications to do it right, which is why we made my Pros & Cons thread a sticky in the Repairs/Mods section!

[beastley]

Originally Posted by Terry England

20' Low-rider Safari (Overnighter) with Hermco Bracket -
Recommendation #1 - Get the 25" 115hp E-tec. They make 129 hp at the output shaft and use a 150 hp lower unit with 2.25 to 1 gears. They are the smallest engine you can get the I-Command gauges with and study everything you could possibly want to know. You'll need to by a couple of gallons of oil a year and need to add about $1.25 - $1.50 per hour of running time for the three year
service interval. I think you may "touch" 35 MPH with a 15 X 17" wheel and will not use more than 25 gallons per day running daylight to dark.

Recommendation #2 - Find a good Salt Water Series 130 Yamaha, Suzuki DF-140, V-4 130/140 hp Carb. OMC, or an older 150 hp 2 two stroke carb Merc., bolt it up and let it eat. Do you know how much gas you can buy for the possible 1 to 1.5 MPG you might gain for $6,000.00? You could run the Great Circle Route twice before you made up the difference!

Mr Marshtackie, Sir.... I like the way your thinkin and I appreciate the recommendations.