1981 Motor Boating Magazine v20 with Merc 200hp

[bigshrimpin]

Check out the performance specs from 1981.

https://books.google.com/books?id=QK9jo73c5gUC&pg=PA67

[bradford]

Sweet!

I love my 150 for gentle mid range cruising, but always thought I'd like a 200 better for hauling the mail.

Their findings of going up 1.5 inches on the transom mounting I find to be also true on my skiff with a hydraulic jack plate, 1.5 is the sweet spot. Would like to try a four blade BRP Rogue or Solas Titan prop though for more stern lift plus she likes to porpoise some on the top end.

Can't believe they ran over an oyster bed on purpose just to get numbers with a damaged prop. WTH!

[Destroyer]

That's a great article, and it confirms what I've thought for a long time. 200 hp is simply better. (Think of a house air conditioner.. too small a window unit and it has to run all the time. Make it bigger and it works less to deliver the same cooling.... in other words, it's more economical) The same with a 200 vs a 150 on our size boats.

At any rate. it was a good article and I thank you BigShrimpin for finding it. I just wish they mentioned what pitch prop they were using in their tests. That would have helped a lot.

[bgreene]

Now imagine the benefits of 300 hp !

But seriously, a couple of things......
1. engine weight - they show the 200hp as lighter than the 175 and 150. I believe it's backwards. Also, at less than 400lbs, all three of these engines are considerably lighter than many current outboards.... my etec 200 hp is more like 525 lbs.

2. engine weight - based on the reality of current 200 hp weight, the 150 truly is lighter, and this has some advantages too........

So, for those with 150hp pushing V's....... that's a very fine choice for these boats, with over 40mph top end, and less weight on the transom.

Engine height comment - I moved one hole further than my shop rigged, and still have 1 hole higher remaining. Might try it.........or not.

[THEFERMANATOR]

Originally Posted by Destroyer

That's a great article, and it confirms what I've thought for a long time. 200 hp is simply better. (Think of a house air conditioner.. too small a window unit and it has to run all the time. Make it bigger and it works less to deliver the same cooling.... in other words, it's more economical) The same with a 200 vs a 150 on our size boats.

At any rate. it was a good article and I thank you BigShrimpin for finding it. I just wish they mentioned what pitch prop they were using in their tests. That would have helped a lot.

The cooling analogy isn't a good one as it has been proven time and time again that a 90-95% duty cycle of an A/C unit is MORE efficient than an oversized unit that doesn't run as much. If an A/C is oversized, the unit doesn't run enough to remove the humidity, yes it runs less, but it uses more electric while running, so you end up using just as much electricity, but don't remove as much himidity leaving your home feeling cold and clammy inside. Going oversized is a common misconception though. And it should be of note that a 1981 200HP MERC is actually a 175HP MERC by todays standards.

Originally Posted by bgreene

Now imagine the benefits of 300 hp !

But seriously, a couple of things......
1. engine weight - they show the 200hp as lighter than the 175 and 150. I believe it's backwards. Also, at less than 400lbs, all three of these engines are considerably lighter than many current outboards.... my etec 200 hp is more like 525 lbs.

2. engine weight - based on the reality of current 200 hp weight, the 150 truly is lighter, and this has some advantages too........

So, for those with 150hp pushing V's....... that's a very fine choice for these boats, with over 40mph top end, and less weight on the transom.

Engine height comment - I moved one hole further than my shop rigged, and still have 1 hole higher remaining. Might try it.........or not.

The 200HP 2.4L MERC WAS lighter than the 150 of it's day. The 200HP engine was a chrome bore or nicasil block whereas the 150 was a steel sleeved engine. And without all the extra crap on outboards, they used to be pretty light. My 225 EVINRUDE only weighed in around 465 pounds or so for the big V-6. SUZUKI had a 225HP outboard with fuel injection, dual plugs, the whole shebang, and it only weighed 470 pounds.

Keep in mind these tests are with carbed 2 stroke engines where raw fuel going out the exhaust ports was common place. The 2.4L engine ALWAYS had an edge over the 2.0L engines, so these results are what I would expect to see. Modern DFI or 4 stroke engines have changed these kind of results quite a bit.

[bgreene]

Interesting info as usual from our assorted group.

I just don't want our V guys with 150 hp to start feeling bad !

My " enormous" 3.3 liter, 200hp HO Etec..........still only runs the V21 to 49+/- mph, so is no faster than the old, light mercury 200.


I bet you're correct THERM, today's DFI 150 likely more fuel efficient than 200 DFI.

[THEFERMANATOR]

DFI's equalled the field out so it brought you down closer to the 1 GPH per 11-13HP across the RPM range. The old rule of thumb for carbed 2 strokes was they would burn 1 GPH for every 10HP they put out. My 140 burned right around 13-15 GPH, my 225 was around 23-25(but it was putting out closer to 250 with porting, so right on track for the 1=10 rule). At cruise you used to go to the north side of this number, but many engines were ALOT higher. DFI's and 4 strokes maintain this balance across the RPM band pretty linearly. So if a hull takes say 120HP to run at 30MPH, a 150/175/200 will all be pretty close to 10GPH fuel burn. I know that with lean burn engines nowadays, they are doing even better than the 1=12 rule.

[bigshrimpin]

as ferm mentioned in 1981 the 200 was a vertical reed 2.4L motor without fingerports and 175 was a 2.0L with the big open exhaust. The 1981 v200 is very close to the same power of the mid 80's 175 . . . it just doesn't have fingerports. So the mid 80's 175 is actually a bit stronger if run it with a 200 exhaust tuner.

This is the combo I run on my boat and it's really really fuel efficient . . . not that we'll be thinking about that with Gas back down to $1.60

This is my cruise with a mid 80's 2.4L 175 powerhead on 200 mid section pushing 23 seacraft. Performance was almost identical with the v200 powerhead.

[THEFERMANATOR]

My 81 150 is the most fuel efficient engine I EVER ran in a large outboard. It was on a bass boat, but I could run for HOURS on a 14 gallon tank. Running along at 3600 or so it only burned 4-5 GPH which was a FAR CRY from my 2.5L XRI 150 I had on my flats boat that burned 11-12 GPH running the same speeds at teh same RPM's with the same pitch prop.

[jamesbalog]

I have an 81 2.4 200 merc on my boat now and love the thing, it replaced an 88 175 johnson. The difference in fuel economy is night and day, the 2.4 merc wins hands down