F200/F175 or smaller?
 

I'm looking for a little help. I know the classic Seacrafts don't do well with a lot of weight on the back of them. I have a 1988 Tracker/Seacraft and just sold the Yamaha F115 off it yesterday. It had 500 hours and was 13 years old. I figured I'd upgrade while I could still get a fair price for it. It only pushed my 20' Open Fisherman about 30mph and to my surprise after installing a fuel flow sensor last week, it was burning 11.9 GPH at WOT to achieve that. I live in Louisiana and a lot of my ridding is in rivers and canals where its very comfortable to cruise at 50mph+. I had my eye on the F200 inline 4 Yamaha or Suzuki. Both are under 500lbs and by old 115 was 440lbs. Didn't figure there would be much difference there. I believe my boat is a little heaver and longer than the classic 20 footers and felt like it could handle the extra weight but would like your opinions. I;m not much on 2 strokes as I believe they will eventually fade out and depreciate quickly. Any advise would be greatly appreciated.

I suspect a different prop would have gotten you to 36mph with a F115? Based on my 33-34 with a F100. My 20MA came with a 175 2 stroke yamaha at 410-415 lb and would touch 50 mph I was told. But I never tried it. A potter 20 is lighter than a tracker, though.

x2 on the prop
I'm also thinking you might want to try the cav plate up ~1.5-2" from the hull bottom (depending on prop) - at least outboards are easy to change.

Yeah. I like the idea of a smaller engine. Just don't like running at WOT. I should have tinkered with the 115 a little more I guess.

Bushwacker is an e-tech guru. I feel that for 4 strokes above 100 hp, they get heavy fast. Like a 4 stroke 150 is often a loser for weight/ hp. But I think(?) an e-tech 130 is a decent tradeoff. Some guys like a suzuki 140. I quietly think it is a tiny bit heavy for a potter 20, but might be ok for a tracker 20. I am not impressed with the corrosion resistance of most anything versus a Yamaha. But I really don't know.

FWIW, I think a 4 blade stern lifting 15" pitch prop on that F115 would have done you justice. I have that on the F100, but it has more lower unit reduction. 2.31:1 versus 2.15:1.

The new Yamaha F115 is almost as light as an older F100/F90. 377lb for a 20"shaft? The F200 is only 110 lb more. But I have no firsthand knowledge.

My cruise for the F100 on a potter 20MA is just under 25 MPH. Even with a kicker and hydroshield.

Verch,
I run an old 20 and get 36 with and old merc I-6 115. I doubt it would get that on your Slacker due to extra length and weight. You may have gotten 33-34 mph tweaking with prop and height but I kind of doubt it.

Respectfully, your opinion of 2-strokes going the way of the dinosaur is unfounded. All Direct Inject 2 strokes are valid and with the exception of those that may be put out of business by their competitors. On a SeaCraft 20, the 2-stroke, direct-injected BRP Etec in 150-200 hp will out perform any 4 stroke in the class by a distance. At 420 lbs, and balls galore your stocky slacker will praise and please you should you take that route. It's 50 pounds lighter, more efficient, and as quiet or better than any of the best 4 strokes in respective categories.

If you can run at 50 in your water, heck, do it! I cant, so I'm content with a 115, But if i lived on a river or lake would I want 50 mph? heck yeah!

Thanks for mentioning the Etec. I took a look at the website and I'll call a few dealers today. I have to be honest, part of my attraction to the Yami and Zuk are the deals on them right now. If I drive 2 hours to Mississippi I can save sales tax and the dealer can get me out the door fully installed with a prop for Suzuki F175/$13k Suzuki F200/$14,500 with a 6 year warranty and Yamaha F175/$14,500 and F200/$15,500 with 5 year warranty. The Etech on a couple websites is $14,500 just for the engine with a 3 year warranty. The Suzuki 175would only be $9k out of pocket after considering the $4k I got for my old Yami 115. Its hard to believe that I could sell a Yamaha 4 stroke for 1/2 of what it was purchased for 13 years and 500 hours ago. So not only am I considering performance, I'm also considering where I'll be in this thing if I decide to sell it in a few years.

[QUOTE=

My cruise for the F100 on a potter 20MA is just under 30 MPH. Even with a kicker and hydrroshield.[/QUOTE]

Wow!! That is impressive, what kind of fuel burn do you get at cruise?

Too impressive. I mistyped my cruise. It is about 24mph for 45-4600 rpm. And 5NMPG.

Thanks for all the feedback. I'm still not 100% sold but leaning toward the Suzuki F175. Its just a couple lbs lighter and a dealer in Mississippi who sells both the Yami and Zuke swares that its ability to turn a larger prop puts it in the same class with the F200 Yami. Your right. Money really isn't the issue here as much as feeling that I made the best selection. Any preferences of the Yami vs Zuke? Most all the reviews I read say the Suzuki performs flawlessly with lots of torque, great mid range and good fuel economy but the downfall is that most say that if they were shopping for a used boat, they are more likely to buy is a Yami is hanging off the back.

Excellent advice! I originally planned to go with a 4-stroke in 2006 when I repowered and really looked hard at all competing motors. I put together a spreadsheet comparing details of all the motors in the 115-150 hp class. (Can e-mail a copy if you send me an address.) As a mechanical engineer, I was most impressed by the 417 lb 140 Zuke, with it's chain driven cams and clever offset driveshaft/crankshaft which provides extra gear reduction without the additional drag of a larger bullet on the lower unit. A local guy offered me a new 140 JohnZukie for about $9K that I almost bought, but his shop was a mess and he sounded like he was from the Bronx, so I passed. (He's now in prison - evidently was a very accomplished scam artist!) However, the Zukes remain my favorite 4-stroke motor because of the unique features they've incorporated to address the valve train complexity and lack of midrange torque common to all the 4-strokes. The bigger displacement 150/175 Zukes have the same advantages but they're much heavier, close to 500 lbs when you look at wet weight with 6-7 qts of oil on board, and numerous Bahama trips with heavy loads convinced me that the 20' hull definitely rides and handles better when you keep the CG where it was designed to be!

I then started looking at the E-TECs and spoke to the BRP engineers at the Miami Boat show in 2004, 5 & 6. They had been watching the problems with the early Optimax and FICHT's for several years and because of their experience with DI 2-S snowmobile engines, were confident they understood the causes and how to fix them. They just waited for OMC to go belly up so they could buy the company for pennies on the dollar! In the meantime, a colleague I had worked with at Pratt & Whitney for many years had left P&W to become the Chief Engineer at OMC's test center in Stuart, Fl., and was there during the transition to BRP. I spoke to him and he said OMC's quality control really went to hell in the late 90's as their financial situation became increasingly desperate, causing them to buy off all sorts of deviated parts from suppliers! He said BRP really cleaned house, threw out all the bad parts, and he was very impressed with the management and engineering team they brought in. He said anything built by BRP was top quality and that I shouldn't worry because the company was trying to overcome the FICHT's bad reputation with extraordinary product support, so they were really standing behind the new motors. So I took a chance on the E-TEC, and have been very pleasantly surprised! After almost 9 years and over 550 hrs, the instant starts, awesome mid-range torque, smooth, quiet operation, low fuel consumption, and lack of problems is still impressing me. Because of it's torque at 3000-4500 rpm, it's actually quieter than the 4-strokes because it doesn't have to be wound up so high - it's nice to be able to converse normally at 30 kts! Although the Optimax appears to be slight better on fuel consumption, I didn't seriously consider it because it's just as loud as the 1975 Evinrude I'd been running for 31 years and I was tired of all that noise! The 2.6L small block V-6 E-TEC is about the same weight as the 140 Zuke, but with 155 cubic inches vs. 122 cu. in. on the Zuke, it's a MUCH stronger motor that doesn't have to work hard at all to push the 20' hull. The 115/130 hp V-4's are also plenty of power for the 20, and used to be only about 375 lbs, but are now up to about 390 lbs, so not much lighter than the small V-6; they're probably running the V-6 lower unit. You might also find some very good deals on the 135 HO, which is just a slightly detuned 150. Most of the E-TEC's actually put out about 10% more HP at the prop than advertised, so be advised that there's serious sandbagging on the power ratings!

When you're shopping, also don't overlook maintenance costs, especially the valve lash adjustments required on some motors at about 600 hrs! Most all the engine makers offer special deals/extended warranties this time of year. I got a 7 year warranty with mine.

I keep hearing about valve adjustments for four strokes. Shim over bucket cam followers practically NEVER need adjusting. Over 10 years onn VWs, Suzuki bikes and Yamaha outboards, I have had to re shim a VW once after 140,000 miles. The suzuki and yamaha didn't need adjustment.

On the Yamaha F100, it took me an hour or two to check the valves. If they did need adjustment, that would be a pain, but they didn't. I did it for peace of mind, knowing that like every other shim over bucket cam follower, it was probably fine, and on the F100, it was. I don't know how many hours are on the motor, I think 800ish. The hour meter say a bit under 700, and it hasn't been plugged in all the time.

Maybe I am the rare guy who maintains his motors? So this doesn't seem like such a cost burden to me. I will do carbs and timing belts and valve lash and oil changes. So that might give me a different viewpoint

Also:
Looking at the Evinrude web page, the 135 is a lot heavier than I thought. I thought in previous years there was a 130 that was the same weight as a Yamaha F90, but it doesn't seem to be available any longer? So it seems like the modern 2 and 4 strokes are closer in weight than I used to think.

Verch,

I think the Yammie and the Suzuki are both fantastic products, but for a 20 of either generation, I would favor the Suzuki 140 over either brands 175, for the approx 80 lb weight savings. I also think the offset drive feature Bushwacker mentioned is a very clever way to keep some weight forward. I believe the 140s performance will be better in every category except top speed, wherein the 175 should beat the 140 but probably not by more than 3 or 4 mph.

If there is one thing I've learned from this forum, it is the "mantra" that "light is right" on a 20 foot SeaCraft hull. A 20 should feel nimble. I don't foresee that sensation with nearly 500 lbs on the transom.

Either way, new power is good. Enjoy!:cool:

I agree with Gillie that the 140 is a better match for the 20' hull than either of the bigger 4-S motors for the best low speed planing performance and ride. My experience with the Seafari, which is still heavier than the Tracker CC models and with more of that weight forward than in a CC, is that the less weight you have on the transom the better. I ran it for over 30 years with a 300 lb motor on some long Bahama trips in rough conditions and was amazed at how well it could stay with 23-24' boats! With only ~ 100 hp at the prop, I could only cruise at about 20 kts and would have trouble staying with the guys running bigger engines in flat conditions, but once seas kicked up to 2-3', they'd have to slow down and then I could stay with 'em! The ride was just amazing and it's too bad that so many CSC guys have never run the 20' hull with a light motor like Gillie has because they'll never know how well it performs when it's balanced as originally designed!

Regarding the E-TEC's, I believe that the 2.6L V-6, which combines the weight of the 140 Zuke with the power and performance of the bigger 4-S motors with even more mid-range torque, is now the optimum new power option for any of the 20' hulls.

The 130 hp and nearly identical 115HO V-4's that were originally listed at 369/375 lbs wet weight (20/25"models) in 2006 had grown to 390/405 lbs by 2009, but as far as I know, only the 115 was available after 2012. The 115 supposedly had more mid-range torque than the 130 V-4, which was evidently replaced by the 135 HO V-6, which I believe came out in 2013. Since the 2.6L V-6 (in 135HO/150/175/200 ratings) offers 1/3rd more displacement with only 28 lbs more weight than the V-4, most folks would probably pick the 135 V-6, provided cost and fuel consumption weren't significantly higher. The other even lower cost and weight option is the 90 HP I-3 E-TEC at 320/325 lbs which is also plenty of power for the 20' hull if you're not interested in running over about 30 kts.

Beating the "Horsepower" Horse to death with a camshaft!
 

Denny, Would you quit pushing those E-Tec Water cooled Chain Saws! We pay good money for outboard motors and we sleep better at night knowing there is extra "stuff" werring around in our engines. Valve springs, cam chains, belts, sprockets, pulleys a such give you a sense of sophistication when you are out on the water. Life is complicated and we need to keep it that way no matter how much it costs. And don't be bring up any of that Pratt and Whitney engineering stuff about "power to weight ratios" or "cost of scheduled maintainaince" because we fully entrenched in the principal that "More is More" and that "Less is More" is just too old school. So wake up and smell the Double Expresso Caramel Micchiato with a splash of Creme de Mint and quit asking for black coffee.

Thanks Bushwacker for all of your input. You certainly raise valid points. I've read through several of your posts as well as other postings on the topic of horsepower/weight issues. I know that without a doubt the small engine is the ticket for the east coast where you see blue water often. The truth is though that I may only see blue water in the gulf once or twice a year and that would only to be to run to the rip or the closest oil rig on a super clear day in the summer. I live about 2 hours form the coast and 95% of the use of this boat will be for pleasure ridding in the bayous and lakes and fishing inshore along the coast. My old Yami 115 weighed 140lbs and the scuppers were fine. I see guys with Yami 150's on these all the time and they are constantly posting about "why cant I get over 40 mph". The Yami 150 weighs the same as the new F200 so I was hoping to hear from some folks like Cayaman who have the F200 or similar engines. Trust me, I know what your saying about lighter is better. I grew up ridding the old 2 stroke dirt bikes that you could easily throw around and now I hate the new heavy four strokes. That would be an easy decision for me but I know how to rebuild those and it isn't nearly the investment of a new outboard. I know that if I cant cruise at least 35 mph in the RPM sweet spot "4-6 gph" I wont be happy with the boat for the long haul. I love the Seacrafts and I knew I was going to be challenged to get new boat options in an older boat but her curves were just too sexy to pass up. So here I am. At a fork in the road.

You know Terry, you may be on to something there. I quit drinking my coffee black when I was about 12. That's about the same time I stopped eating liver & onions and hunting with a crack barrel shotgun. Hell, last year I traded my M1A (16lbs) for Scar 17 (8lbs). I don't always think newer is better but I like what I like. I love the slim sexy lines of the Seacraft 18 & 20 but I cant live with 30-35 mph WOT. Maybe I chose the wrong boat for what I use it for but for now, I still love it and want to try to get the best engine fit that meets my needs without compromising the strength and functionality of the boat. I'll never be the guy in the left lane of the interstate driving 50 mph. It just isn't me. So if your comfortable sitting on your porch drinking your black coffee with your crack barrel shotgun throwing rocks at the new cars as they pass your house, keep on keeping on bro. It just aint for me.

You have a good point Terry - I used to put more stuff in my coffee but switched to black coffee a couple years ago just because it was simpler and less hassle! Somebody's avatar on here says "Life's too short to own an ugly boat"! I don't drink cheap whiskey and the same rationale should probably apply to other stuff as well - no point in ending up as the richest guy in the graveyard! Maybe I'll even go ahead and cash in that annuity I've been thinking about!

verch - If I lived where you did and ran in flat water all the time, I'd probably be looking for more power and speed too! You're definitely on the right track by trying to keep everything light, but if you want 5-8 mpg @ 35 mph in a 2000#+ deep-V hull, I'm afraid you're gonna be disappointed with any modern motor, even if it's on a SeaCraft! No Bones 20 CC will run about 65 with that souped up "200" 2-S Merc and I'm sure it'll cruise at better than 35, but I bet he'll burn a tad more than 6 gph doing it! Your best bet might be to just go ahead and buy whatever you think will have the best resale value a couple years down the road, and then keep an eye on the G-2 E-TEC! Weight looks kinda high but also includes hydraulic steering and a 2 gal oil tank, so hard to do apples to apples weight comparisons. They're claiming 15% better mpg than existing 4-strokes, so by the time they get done slicing and dicing that new 3.4L 300 hp V-6 into I-2's, I-3's, and V-4's a few years from now, like they did with the current 2.6L V-6, they might have about what you want! A 150 hp I-3 or a 200 hp V-4 would most certainly be lighter than anything currently on the market! Denny

The Tracker hulls are not as sensitive as the Potter boats to weight aft. If the boat is intended to run 50+mph in smooth water, and there's no need to be able to stay on plane below 20mph, the CG will want to be further aft than a Potter that's bound for 3'-4' seas.

You might be fine with a 500 lb. 200hp motor as long as you don't hang it on a bracket. Check the bottom of the hull from the transom forward about 4' with a straight edge and look for hook. My 20' '83 Seacraft Industries hull has some hook and it keeps the bow low at speed. If yours has some hook in it, that will work in your favor with a heavier engine.
Dave

Dave,

I didn't realize the Tracker models had a hook in 'em! Probably makes sense as they were newer boats and rigged with heavier motors. Is it just the innermost panels or do the other panels also have a hook also?

Didn't we find some rocker in the aft 3-4' of the innermost panels on that Potter 20 CC project boat you picked up? I think that rocker would provide more speed potential than a boat with a hook because you could get more hull out of the water at high speed, although it would be more sensitive to motor weight and CG location.

I was doing some prop testing in flat water on my stern-heavy rig last week and noticed that, at about 25-28 mph, I could trim out to about 50% trim with no porpoising. As I increased speed at the same trim setting however, it would start to porpoise once I got up to about 35 mph! The '69 Boating Magazine test data (attached) on the 20 Seafari shows an increase in running angle above 35 mph, and I suspect that may be a result of some rocker built into the Moesly/Potter hull. That should provide some extra speed in a normally balanced hull, but if is a hull is already stern heavy, I could see how that rocker could make it less stable at high speed! (Carl said the CG on the I/O models is further forward than on the OB models, and it's definitely further forward than it is on mine with the bracket and heavy motor!)

I'll tell you what Bushwacker, I'm sure disappointed after looking closer at the Suzuki numbers. I pretty well had my mind made up after talking with a dealer that had me convinced that The Zuke DF175 was equal to the Yamaha F200. Before pulling the trigger, I decided to look over the boat tests on the Suzuki website and to my surprise, the DF 175 had the exact same numbers as the DF 150 other than it was getting less MPG on average. They ran each motor on an Angler 220FX (2400lbs) and a Bluewave 2200 (1750lbs). I was thinking that I could get 50 mph out of the Zuke 175 but after seeing that top speed on the Angler is 45 mph with either motor, I have to question if gaining 5mph is worth $5k to advance to the Yamaha F200. Right now, your suggestion of getting something to hold value for a couple years is making a lot of since. Maybe a Yamaha or Suzuki 150 is the ticket for now. Who knows. With the right prop I might even get a little better than the study with the Angler 220FX. I'd like to think the Seacraft hull design would out perform the Angler. It sure would be nice if the Suzuki 140 would get me over 40 mph. That would be an easy choice at 400lbs but it seems like any 4 stroke to push the boat over 40 mph is going to weigh in the range of 485lbs.

Thanks for mentioning the "hook" Dave. I took a straight edge to my hull and I don't see any variation in the suggested area. I'm not exactly sure what I should be looking for but it is straight as an arrow for at least 8'-10' from the transom. When refinishing the boat, I pulled off the cover to the compartment that houses the fuel tank and the tank was at some time replaced with a 35 gal. aluminum tank that I could move aft another 2' if needed. The boat was pretty darn well balanced as it was with the 440lb F115 so I didn't mess with it then. It would be a pain to tear into it again to push the tank forward but I could always do it if the extra 60 lbs from the new motor became an issue.

Denny,
I wasn't sure about the Tracker 20s, or whether hook was something Tracker phased in over time, that's why I suggested the straight edge check. A friend of mine picked up an '88 23CC a few months ago and it has some hook in all the hull panels, both starboard and port. That doesn't mean all the Tracker boats have it. There may have been some changes made between production runs. Who knows?


Verch,
There's a lot of "lore" about these hulls, some of it reliable, some not so much. The layup schedule can be significantly different from one boat to another spanning three or more manufacturers. On the '88 23 I mentioned above, my friend pulled the through-hull bilge pump discharge out, and the hull side was 1/2" thick, much thicker than you would expect to find in a Potter boat.

I think the take-away from this is that if your boat ran ok with a 440lb. 115, it will be ok with slightly more weight in a higher horsepower motor. I don't have any hard data, but I think the Potter 20s, because of the rocker Denny mentioned, and probably lighter weight, may be faster boats than the Seacraft Industries and Tracker boats with the same horsepower. If you want to hit 50mph, you may have to go to a 225. It's only one data point, but my Seacraft Industries 20 runs mid 40s mph with a 200 2-stroke carbed Merc.

Sorry if I've injected uncertainty into the conversation, but there's a bit of a wild card element when we talk about post-Potter hulls.

Dave

Please Dave, don't apologize. I'm here to learn and I value the feedback that you all provide. Maybe one day I'll have a nugget that I can offer. For now, your right. There are so many variables to these boats over the years that I have much to learn. It is reassuring to hear from folks out there running 20' Seacrafts of all ages with motors weighing upward of 450lbs. It helps put things into perspective.

During the Moesly era, Merc did extensive comparison testing at Lake X of VDH hulls and conventional deep V's with the same weight and HP, and they concluded that the VDH was about 10% faster, so your boat might be about 10% faster that that Angler with the same power if weight is similar.

PowerBoat Reports did a great comparison test of all the 150 HP motors back in June 2006, so I dug out my copy and have posted the last 2 pages below which contained all the test results. I summarized all the data in a plot vs. RPM. All motors were mounted on identical Angler 204FX 2200 lb, 8'x20'4" hulls. The only gripe I have with the test is that ALL tests were done with the motors trimmed FULL DOWN! I"m sure they would have all picked up more speed if the motors had been trimmed out as far as possible! They did that just to make things equal because they didn't have trim gages on every motor. The tests would have been more meaningful if they had tested each motor at the optimum trim for the particular prop it was running, but I'm sure that would have taken longer, and those guys clearly weren't operating to the same aerospace performance test standards I was used to!

Verch,

You got some good feedback from the guys. I will chime in some here on a couple of notes.

I am in Idaho and 80% of what i run is Glass on the Lake. With 20% on the Columbia river which is always blowing up 3' 4' all the time and some Offshore Oregon Tuna Runs. So Here's what i came too...

Been an Evinrude guy a long time... Here are some Options...

Carb - Johnson Ocean Runner - 150 to 200hp. 380 lbs and Plenty of power. The down side.. .Not so good fuel economy compared to todays Engines.

Next up is the Etec - U can Run the Small block v-6 close to 428 lbs and here is the kicker....

135 HO - Low water pick up and Putting out close to 150 HP. Cheaper than the 150 same horsepower as the 150 or close too it.

150 Etec - Bushwhacker has this engine... Plenty of Torque / Speed but probably not a 50MPH boat.

then the 175 or 200 Etec.. .NON G2 ....

I strongly Considered the Etec 200.

Flying Frizzle put a 225 Merc EFI on a bracket on a 20' Sceptre. Speed 60mph plus... chine walking at 60. Weight 480 lbs


With all that being said...
Strick has a 140 zuke on a 20' sceptre speed around 44mph on a bracket.

The 150 and 175 Zuke are in a whole nother league than the 140. They can spin a big prop and the 140 is not a super strong 140.

The Yammies are priced Considerably Higher but hold great Value.


I would encourage you to go Look at the zukes again on Test boats between the 150 and 175. Pay attention to the type of Hull those engines are on. When you really start looking most are what i would call a PLOWING type design.

Someone Posted Up last year a 23' Sceptere with a 175 zuke pushing 43mph... and that bastard weighs in at 3300 lbs dry.


I can tell you this....

I am now Narrowed down too 2 choices for me on the 20' Seafari.

The 175 Zuke Mounted on a 10" Hydro Dynamics Bracket with a POWRTran 7" Electric Jack Plate for optimal Trimming and Speed.

OR

I am going to buy a 1995 to 1998 Johnson Ocean Runner 200hp and hang it on the same set up. The cost between the 2 engines is about

ZUKE - $13,000

OMC Ocean Runner - $2000 plus $2000 For Hopped UP Rebuild Total is $4000 plus the Brackets.


I am going to make a decision Soon.... I love the Zuke Technology. But Dam i can buy a ton of gas for $10,000 and... have a Super Reliable Engine at 385 lbs with massive Power.

The Johnson Set up is probably a 60mph boat plus.

Have no idea if that gives you any insight but after Hours and Hours of countless consideration I am down to those 2 choices.

Regards,
Robert

The 3.0 (225-250) mercury's are a little heavy for a 20' hull. The tag on my motor actually says 438 lbs but that's with out the prop and the oil in the tank, dry weight. The Web says it is 445 lbs. I am thinking about changing it out to a 2.5 liter 200 hp efi mercury. They weigh in at 398 dry and get me under that 400 lbs mark that everyone says you need to be under. I figured a little more weight wont hurt like you said and it doesn't seem to that terribly bad but just enough that i would like to rig a 40 lbs lighter motor to see just how much it will help balance. Far as an four stroke the zuke 140 is about the biggest I would go with at 420 lbs. The Yamaha 150 is 466 lbs, still heavy. The Yamaha 200 inline four cyl four stroke is 489 lbs, heavier but some up here has used them tho claiming fair results. The Yamaha 115 at 412 lbs would be a great choice if you could handle only having 115 hp again.
I would say that if you want a newer four stroke the 140 zuke is hard to beat, but the power of a inline 4 Yamaha would be sweet but you better do everything to get the weight right that you can to maintain balance. There are a few up here that done the i4 and loved it. Being you boat is the tracker with the 25" transom, higher decks and the 20.4 length it should handle the extra weight much better than the older potter era 19.8' hulls. I like having the extra power and after running the 115 you will like the extra power the 200 will have.
If you can talk your self into a two stroke the e-tech and the opti's are great motors that weigh less than most 4 strokes of the same size hp. They are the way to go on a 20' hull in my opinion in stead of an heaver four stroke. The newer motors weigh more than the older ones but get better fuel mileage with the direct injection. Always a trade off. You can save the money and weight by getting an older power, even tho it will use more gas, you will save so much on the purchase that you will be able to buy a lot of fuel before it ends up costing more to than a new motor. But after having a newer f 115 I doubt you want to go to an old two stroke. It's all a trade off, you just got to figure on what will best fill your needs.
The main thing is watch you balance and do what you can to keep the weight forward no mater what you go with.

"Carb - Johnson Ocean Runner - 150 to 200hp. 380 lbs and Plenty of power. The down side.. .Not so good fuel economy compared to todays Engines"

Not so good fuel economy.........The understatement of the year!!! No need to ask me how I know? I had no idea that much gas could flow through a 3/8" fuel line in a single fishing trip!!!! :)

fat kid, seesaw, horse, water, dollars, sense - this thread has it all:rolleyes:

Rag'in Cajan
 

Yep, I'm puzzled too
Here are the Gentleman's Specifications, Gillie -
50 MPH
4-6 GPH
4 Stroke
<400#'s
A River Racer with occational Offshore Oil Platform Capability
(I guess that's a foot throttle on a CC?)

I'm think'in a 2.5 EFI Bridgeport with a 20" leg Speedmaster. What wheel would he need and where's the Saw-zall? (I think The Padre knows where there's a Mark 78 with stacks too)

We'll get this all sorted out, but right now I'm sitting on my carbon fiber front porch swing, with my model 1955 Winchester Model 12 resting against the wall, and a 5 gallon bucket of rocks, just waitng for a Beemer or an Audi to come by! (I parked the 7.3, F-250 on the side of the house because I don't want to hit it)

Wait a minute Uneasy Rider, "I ain't even got a front porch - you can call home and ask my wife!"

Wait til we start talkin` props.

Mr Whacker almost hit 50 with his e tec. 49. sumting.

Wi tu lo,
GFS

T he he, diarrhea can come from more than one place. I have been known babble from time to time too...

Who woulda thunk buying an outboard could be so entertaining.

We would.

Sandy, the Ayatollah Bushwacker is going to lay a Fourstroke Fatwah on us if we don't get this straightened out - he needs either twin Bearcats with Speedmaster gear cases or a Rolls-Merlin Go-Devil

- If you can't take a joke, you shouldn't own a boat!

Everything on my 20 is broken. I am going to remove my bow light and rebuild everything
below that.

Dang, Terry, now you got my squirrels running - what if I kinda double+ my chevy230 with a Packard-variant Merlin. Good enough for the P-51, Ought to be good enough for the Moesly 21, no? Pappy Moesly might be pleased - maybe? Change her name to "Mosquito." Weight forward, power to fly, full use of dem lifting strakes? Up the river with no need for a paddle? Out to the rigs in time to re-fuel? Might need a bigger fuel cell but there's a lot of room in the bilge of the 21. Might have to ditch the outriggers...whaddaya figger she'll idle at? Dem outriggers aint cheap:cool:

PT-6 Gas turbine. :D
Ask Denny about it - I'm pretty sure he was at Pratt when they did it...

455 lbs, Four stroke, simple to work on, great on fuel, not to heavy and cost is very competitive: 150 mercury Four stroke 3.0

https://www.youtube.com/watch?v=duxWXmudd24

If the motor in the link dose not work out for your needs try these:

Attachment 9480

[QUOTE=flyingfrizzle;234369]455 lbs, Four stroke, simple to work on, great on fuel, not to heavy and cost is very competitive:

https://www.youtube.com/watch?v=b4xq...layer_embedded

If the motor in the link dose not work out for your needs try these:

Attachment 9480[/QUOTE

LMAO Frizzle - Of course i click the link to Youtube.

and it say.... DOES NOT EXIST!!! LMAO...Too funny.

I am thinking now I want...

ONE of these on a 20' Seafari
https://www.youtube.com/watch?v=yeh4dAsNptQ

Just the Motor... No Boat!
Ha..