V-8 jetboats are dead?

rifleman

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Last week, I stopped by a boat dealership looking at some of their jetboats on the lot. Soon, a salesman walked over and in a friendly and helpful manner inquired if he could answer any questions. We talked a few minutes about the nearest boat with a mercury 200 hp sportjet.

I don't have a boat with an inboard, although inboards interest me and maybe someday I might like to own one. So after the salesman tells me a few things about the sportjet, I ask, "Do you have any V-8 powered jetboats for sale?" He said, "V-8s are dead." He went on to describe power-to-weight ratio advantages of the sportjet and its superior fuel efficiency. He also said that V-8s are no longer the best inboard motors having been originally designed for automotive use, and not optimized for constant high rpm use.

So, I'm wondering if it's nowadays widely believed that V-8s are obsolete for jetboats? Sure, they're about twice as heavy as a 200 hp sportjet, but aren't V-8s the only practical way to get more than 300 horsepower? By the way, which is more reliable, the sportjet, or a V-8?
 

alaskanmoosehunter

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Personally, I'm a outboard fan with the mercury optimax as an exception.

I'm also witnessing the death of the V8 boats. Lots of them on the lemon lots, craigslist and alaskalist. The 70's and 80's are over and gas is through the roof, hardly no one can afford to run them. I see alot of the V8 boats being converted to handle large outboards instead. I think only thunderjet and simular boat works are still outfitting with large FI V-8s

Yep, power to weight ratio is probably better with a sportsjon or simular boat...But like they say, "They don't build them like they use too." I would much rather take my chances in a big, beefy, quarter inch thick, inboard V-8 running a boulder patch of river than the sportsjon.

Otherside of the coin:
I would rather try getting a sportsjon off a gravel bar than a V-8 of any kind.
 

Bethell

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you no yankey my wankey

you no yankey my wankey

Anybody try powering an inboard jet with a wankle (sp?) rotary engine, like in a Mazda RX-7 ? Small, light, powerful, fuel injected...turbo any one?
 

broncoformudv

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All the major manufacturers are still building boats with inboard V8's.

Weldcraft
Thunderjet
Wooldridge
Custom Weld
Hells Canyon Marine
Northwest
Duckworth
Customweld
etc

Yes a lot of the cookie cutter companies have switched to the Merc Sportjet, because they are cheaper to build.
 

chriso

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Everybody's certainly entitled to their opinion...

Everybody's certainly entitled to their opinion...

Last week, I stopped by a boat dealership looking at some of their jetboats on the lot. Soon, a salesman walked over and in a friendly and helpful manner inquired if he could answer any questions. We talked a few minutes about the nearest boat with a mercury 200 hp sportjet.

I don't have a boat with an inboard, although inboards interest me and maybe someday I might like to own one. So after the salesman tells me a few things about the sportjet, I ask, "Do you have any V-8 powered jetboats for sale?" He said, "V-8s are dead." He went on to describe power-to-weight ratio advantages of the sportjet and its superior fuel efficiency. He also said that V-8s are no longer the best inboard motors having been originally designed for automotive use, and not optimized for constant high rpm use.

So, I'm wondering if it's nowadays widely believed that V-8s are obsolete for jetboats? Sure, they're about twice as heavy as a 200 hp sportjet, but aren't V-8s the only practical way to get more than 300 horsepower? By the way, which is more reliable, the sportjet, or a V-8?

Your experience brings to mind a few thoughts if you dont mind me sharing?

In my opinion the two boats uniquely serve different purposes, and meet some similar "overlapping" purposes with varying degrees of effectiveness.

1) Either one will get you on the water.
2) In general, the SJ will run a bit shallower due to its lighter weight
3) In general, the V8 will haul a heavier load more readily
4) In general, the SJ will burn less fuel than the big block V8's, though the fuel burn on the modern small blocks is pushing pretty strong at equaling SJ comsumption. Especially when you run the SJ at heavily loaded conditions, then the fuel burn on them isnt so pretty either.
5) Purchasing a SJ is certainly more economical up front than a V8 and Jet pump, to the tune of many thousands of dollars.
6) For most recreational users, engine and jet life on the SJ is more than adequate, and even though I believe the V8 and Hamilton or Scott pump combinations to be more industrial strength, the average personal user wont necessarily come up against any huge issues in engine or jet life.
7) Getting a boat unstuck is tough to be objective about. I remember the day back when I worked like a dog to unstick a 18' flatbottom with a 35hp outboard on it. And I've unstuck 24' big blocks more easily in some cases. The riverbottom conditions, your experience in getting unstuck, the weight of the boat, the caliber of your crew/passengers in working through it, what kind of equipment you have for getting unstuck, these all have a much greater role in how tough it is to get unstuck than which boat you happen to be in (from what Ive seen anyway)
8) I'd venture to guess the salesman you were speaking with had some bad experiences with bigger boats and truly believed what he was telling you based on his experience, unfortunately (IMHO anyway) that may or may not be the whole story from the collective experiences of all a lot of folks out there who have a ton of experience to bring to the table for discussion. It'd probably be worth considering and looking at all your options as you seem to be rather than making a decision based solely upon that one guys opinion.

FWIW, my last V8 and jet combo weighed in at 250 more pounds more than the SJ package (far less than double the SJ weight) but is pushing 500 hp and 500 ft/lbs of torque. (which is at least double what the SJ will put out)
My fuel burn is 8 gallons per hour no matter how hard I run it, and it'll haul easily twice, if not 3 times what my SJ will. (and it has REAL heat for when it gets cold out!)
 

Roger45

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Anybody try powering an inboard jet with a wankle (sp?) rotary engine, like in a Mazda RX-7 ? Small, light, powerful, fuel injected...turbo any one?

I have a brother in California that is really into the rotar engines (cars) since they first came out. I specifically talked to him about putting one in on an air boat. He thought that they would work great for a short period of time, but the other variables would prevent anyone from seriously using them...if I remember right, heat, exhaust weight, and the constant need to rebuild being but three reasons...
 

Akgramps

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Interesting motor from Atkins rotary marine.
http://www.atkinsrotarymarine.com/
Chriso: 8GPH w/500/500 V-8 is very good, I have heard the sj's can burn more than that when you start getting some weight in the boat.
MarineEngineMain1.jpg
 

bkmail

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Rotary on an airboat

Rotary on an airboat

I spoke w/a guy who had a rotary engine on his airboat, claimed it was great. Of course he was trying to sell it...wanted something w/more umph.
So it's already been done.
BK
 

chriso

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Chriso: 8GPH w/500/500 V-8 is very good, I have heard the sj's can burn more than that when you start getting some weight in the boat.

I know, the newer V-8 motors are getting lighter and more economical (unless you calculate initial purchase price maybe!;)) If you can trust the mercury smartgauges (and I do) its all you can do to hold 8 gph fuel burn rate on my 250 SJ, with any kind of a load its common to be in the 11-12 gph range. My best fuel economy previously with a V8 was 11 gph on a 350 we had, the 6 liters about 13, the big blocks 14-15.
 

wildog

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Dead?

Dead?

No, not dead. That's a salesman talking.
What, is Obama making a cash for clunker boat program now?
They are in full force.
Try putting a moose, a bear, three guys, a barrel of fuel or two and everything else in a sportjohn and take off. I'm sure you would enjoy a big block much better in that case.
 

Ellamar

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Try putting a moose, a bear, three guys, a barrel of fuel or two and everything else in a sportjohn and take off. I'm sure you would enjoy a big block much better in that case.

Done it, Sportjon barely broke a sweat...and burned less fuel than the big blocks doing so.

Nothing against the big blocks, my hunting partners have big blocks and 212's in their Wooldridges and are great boats. From what we've found on our hunting trips is the Sportjon will haul every bit as much weight a little more economically, which makes a difference when you're 400 river miles from home. Downside is they're loud, but that's overcome by a good set of Bose headphones and an iPod...

Some day I'll make the move to a 23' Wooly Sport Drifter with a big block and 212, but not until by two sons are big and strong enough to help Daddy push it off a gravel bar...
 

Crumm

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The SportJet is a awesome motor/pump and serves it purpose well. I had one for four years and really enjoyed it. Power to weight ratio and fuel economy can't be beat but there are some drawbacks. Noise and vibration get old after a while and they don't put out enough heat to efficiently run a heater. The dealers will sell you a heater but they only work close to wot and will probably overheat your engine at some point due to plugging up. My next boat this fall or next summer will be a 14' or 16' flatbottom/tunnel with a 35 Honda factory jet and then the summer of 2011 I will add a 21' or 22' Hardtop with a 6.0/212 to the fleet. I think these two boats will serve my needs much better than one do it all boat with a sportjet. So in my mind no V-8 jetboats are not dead they just have more competition than they use too. Nothing quite like the rumble of a V-8 when you get tired of the ear piercing sportjet scream but the sportjet will get you and a big load where you want to go.
 

Nitroman

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Your experience brings to mind a few thoughts if you dont mind me sharing?

In my opinion the two boats uniquely serve different purposes, and meet some similar "overlapping" purposes with varying degrees of effectiveness.

1) Either one will get you on the water.
2) In general, the SJ will run a bit shallower due to its lighter weight
3) In general, the V8 will haul a heavier load more readily
4) In general, the SJ will burn less fuel than the big block V8's, though the fuel burn on the modern small blocks is pushing pretty strong at equaling SJ comsumption. Especially when you run the SJ at heavily loaded conditions, then the fuel burn on them isnt so pretty either.
5) Purchasing a SJ is certainly more economical up front than a V8 and Jet pump, to the tune of many thousands of dollars.
6) For most recreational users, engine and jet life on the SJ is more than adequate, and even though I believe the V8 and Hamilton or Scott pump combinations to be more industrial strength, the average personal user wont necessarily come up against any huge issues in engine or jet life.
7) Getting a boat unstuck is tough to be objective about. I remember the day back when I worked like a dog to unstick a 18' flatbottom with a 35hp outboard on it. And I've unstuck 24' big blocks more easily in some cases. The riverbottom conditions, your experience in getting unstuck, the weight of the boat, the caliber of your crew/passengers in working through it, what kind of equipment you have for getting unstuck, these all have a much greater role in how tough it is to get unstuck than which boat you happen to be in (from what Ive seen anyway)
8) I'd venture to guess the salesman you were speaking with had some bad experiences with bigger boats and truly believed what he was telling you based on his experience, unfortunately (IMHO anyway) that may or may not be the whole story from the collective experiences of all a lot of folks out there who have a ton of experience to bring to the table for discussion. It'd probably be worth considering and looking at all your options as you seem to be rather than making a decision based solely upon that one guys opinion.

FWIW, my last V8 and jet combo weighed in at 250 more pounds more than the SJ package (far less than double the SJ weight) but is pushing 500 hp and 500 ft/lbs of torque. (which is at least double what the SJ will put out)
My fuel burn is 8 gallons per hour no matter how hard I run it
, and it'll haul easily twice, if not 3 times what my SJ will. (and it has REAL heat for when it gets cold out!)

Bovine feces.
 

RadFisher

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I have a 21' Customweld Storm Inboard jet boat with the V8 engine that I use now down on the Columbia River near Portland - Vancouver. My wife and I are planing to move to Alaska, and I'm wondering if I'm going to be able to use this boat in many places, (ocean, bays, rivers, lakes) Should I sell this down here and buy a boat that will be more suited for up there, or keep it and be able to enjoy usung in many places there in Alaska?

Thanks!!!!


I'll make a new post on this matter in hopes of getting more responses.
 

Crumm

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I have a 21' Customweld Storm Inboard jet boat with the V8 engine that I use now down on the Columbia River near Portland - Vancouver. My wife and I are planing to move to Alaska, and I'm wondering if I'm going to be able to use this boat in many places, (ocean, bays, rivers, lakes) Should I sell this down here and buy a boat that will be more suited for up there, or keep it and be able to enjoy usung in many places there in Alaska?

Thanks!!!!

There are hundreds of rivers and lakes in Alaska where that boat would be perfect.
 

jrogers

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I have a 21' Customweld Storm Inboard jet boat with the V8 engine that I use now down on the Columbia River near Portland - Vancouver. My wife and I are planing to move to Alaska, and I'm wondering if I'm going to be able to use this boat in many places, (ocean, bays, rivers, lakes) Should I sell this down here and buy a boat that will be more suited for up there, or keep it and be able to enjoy usung in many places there in Alaska?

Thanks!!!!


I'll make a new post on this matter in hopes of getting more responses.


In my opinion, an inboard jetboat is the best all around boat for southcentral alaska. You can take it on the ocean as well as in the rivers and lakes. We used ours for waterskiiing and tubing, the big sue and the little sue, (starting at the inlet from the port of anchorage), whittier shrimping, silvers in seward and homer halibut. The only place it cannot be used is the Kenai due to the 50hp limit, although I even had mine in there a few years ago (should have taken a picture, it was probabily the last 24 V8 jetboat to be at a dock in the kenai for a while).

Bring it!

Jim
 

Ellamar

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Noise and vibration get old after a while and they don't put out enough heat to efficiently run a heater. The dealers will sell you a heater but they only work close to wot and will probably overheat your engine at some point due to plugging up.

Noise and vibration are a major drawback, that's for sure. As long as you're above 2200 rpm, it'll kick out heat. At cruise it pumps out just as much heat as at WOT.
 
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