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How high will a 49ci motor rev?

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 PostPosted: August 5th, 2016, 10:36 am   
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jake@elsey.ca wrote:
Phillnjack. How many race engines have you built, raced, or tested?

Don't be so quick to bash people on this site please. You don't appear to have any credible experience doing anything with a three cylinder engine. Is your only knowledge of race engines acquired through staying up late reading online forums?

A strong 49 is better than a stock 56, and I have the race footage and experience to back it up, as do many others. A few years ago craig Fraser ran a similar setup too. A stock 49 on a big foot in T750 ran ~58 with zero setup time.

You can't really claim to know anything - so try to be nicer, ya?
The wife should take your keyboard away I think...


I got a good laugh and then left it alone. I figured you'd be here at some point to post your 49 experiences.

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 PostPosted: August 5th, 2016, 10:44 am   
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So all you out there have bone stock.fishing motors totally untouched doing 6500 rpm with 24 Rakers ?

BULLSHIT.


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 PostPosted: August 5th, 2016, 10:49 am   
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Post above running 75hp 1.86 ratio 75hp.
What revs and what prop ?

I believe your speed.
But that's a faster engine than a 1985 70hp.
The 75 was ported differently.


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 PostPosted: August 5th, 2016, 11:07 am   
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It's a 49cube 70 on a shorty mid with a shorty large case, not a long shaft leg.
I've seen the boat numerous times fly by and it sure looks close to 60 from the deck.
But I am a huge fan of the suds.


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 PostPosted: August 5th, 2016, 11:31 am   
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stock 49er doing 70+ reving 6800 (listen at the end) 29 years ago
https://www.youtube.com/watch?v=41b49FieyR8


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 PostPosted: August 5th, 2016, 1:10 pm   
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Yes the engine could be stock total untouched doing 7200 rpm.
But no stock fishing 49 will pull a 24 raker to 6500.
There is 49 cu in around doing 80mph. But they not running 2.42 at 24 rakers.
The prop is way too big for an Un modified to pull those revs.
I am talking stock fishing motor. No race reeds head work port work piston mods tuner mods trick pistons.
Those 49 engines did not rev high unless cleaned up and ported.
Some call a blueprintedengine stock, that is not correct. Any internal work is a modification.
None of you are getting what I am saying.
I not debating 70 plus mph from model 49. Not debating what anyone has ever got regarding their rpms from a 49.
What I am saying is out the crate the 49 will NOT run a 24 raker at such high revs.
Omc did not make it to run that power, they made race motors to get the revs with big props.
And the short mid don't make any difference to revs v longer mid.
Both gearbox at same height v bottom of boat makes no difference to revs.


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 PostPosted: August 5th, 2016, 2:36 pm   
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Joined: September 24th, 2012, 7:46 pm
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jake@elsey.ca wrote:
Phillnjack. How many race engines have you built, raced, or tested?

Don't be so quick to bash people on this site please. You don't appear to have any credible experience doing anything with a three cylinder engine. Is your only knowledge of race engines acquired through staying up late reading online forums?

A strong 49 is better than a stock 56, and I have the race footage and experience to back it up, as do many others. A few years ago craig Fraser ran a similar setup too. A stock 49 on a big foot in T750 ran ~58 with zero setup time.

You can't really claim to know anything - so try to be nicer, ya?
The wife should take your keyboard away I think...


Jake, did he do more setup with the big foot gear case after running it in T750? Im basically in the same spot, almost no setup time and it runs 57-58 consistantly. Wondering how fast i could get mine going before getting a nitro case. Id love to try a big pitch cleaver when i get my motor up higher


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 PostPosted: August 5th, 2016, 4:42 pm   
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phillnjack wrote:
Yes the engine could be stock total untouched doing 7200 rpm.
But no stock fishing 49 will pull a 24 raker to 6500.
There is 49 cu in around doing 80mph. But they not running 2.42 at 24 rakers.
The prop is way too big for an Un modified to pull those revs.
I am talking stock fishing motor. No race reeds head work port work piston mods tuner mods trick pistons.
Those 49 engines did not rev high unless cleaned up and ported.
Some call a blueprintedengine stock, that is not correct. Any internal work is a modification.
None of you are getting what I am saying.
I not debating 70 plus mph from model 49. Not debating what anyone has ever got regarding their rpms from a 49.
What I am saying is out the crate the 49 will NOT run a 24 raker at such high revs.
Omc did not make it to run that power, they made race motors to get the revs with big props.
And the short mid don't make any difference to revs v longer mid.
Both gearbox at same height v bottom of boat makes no difference to revs.


Stock motor or not, you can't compare a race boat like ours to your tug boat Phill. Not much touching the water once you get to a certain speed. As for spinning a 24 pitch prop with a 2.42, don't see any reason why you can't spin it. We are spinning 22, 23 and 24" with 1.87 gears at 6,000 to 7,200 RPM


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 PostPosted: August 5th, 2016, 10:01 pm   
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13Checkmate wrote:

Jake, did he do more setup with the big foot gear case after running it in T750? Im basically in the same spot, almost no setup time and it runs 57-58 consistantly. Wondering how fast i could get mine going before getting a nitro case. Id love to try a big pitch cleaver when i get my motor up higher


Unfortunately no, we didn't get any further as it was clear it had the potential to be, and was definitely too overpowered for the class, so that engine can only be run under the "fair competition" rule, and not for points.
I wouldn't really know what advice to give you other than take off the airbox and get your jetting/timing nice and tuned. I don't know any tested tricks with that big foot.

Worth a try?: Hounddog, as well as myself, have been waiting for someone to try the 2.41 ratio in a nitro. Gears from a 2cylinder 60. The only worry is whether or not the gears can take it? I would think they'd be fine. Who knows!

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 PostPosted: August 5th, 2016, 10:13 pm   
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Damn, i can see why they wouldnt let it in T750. It would pull much harder then a 2 cylinder would corner to corner i would imagine.
That would be interesting with the 2 cylinder gears in a nitro. The bigfoot at the height im at gets hairy when pulling the throttle back quickly when coming into boat wake, it handles awesome other then that. The boat gets on the pad and is very stable.


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