It is currently April 28th, 2024, 10:51 am

How high will a 49ci motor rev?

View active topics

All times are UTC - 5 hours [ DST ]


Post new topic Reply to topic  [ 34 posts ]  Go to page Previous  1, 2, 3, 4  Next
Author Message
 PostPosted: August 5th, 2016, 10:36 am   
Drag Racing Sponsor

Joined: October 30th, 2012, 12:14 am
Posts: 697
Location: Palmerston
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.

_________________
Image
13' Rapid Craft 15" OMC 56
13' Critchfield 15" OMC 56
19' Laser 380 Ray (Future Project)


Top
 Profile Send private message  
 PostPosted: August 5th, 2016, 10:44 am   
Member
User avatar

Joined: September 15th, 2015, 2:35 pm
Posts: 392
Location: Slough, England UK
So all you out there have bone stock.fishing motors totally untouched doing 6500 rpm with 24 Rakers ?

BULLSHIT.


Top
 Profile Send private message  
 PostPosted: August 5th, 2016, 10:49 am   
Member
User avatar

Joined: September 15th, 2015, 2:35 pm
Posts: 392
Location: Slough, England UK
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.


Top
 Profile Send private message  
 PostPosted: August 5th, 2016, 11:07 am   
Member

Joined: August 25th, 2014, 1:56 pm
Posts: 27
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.


Top
 Profile Send private message  
 PostPosted: August 5th, 2016, 11:31 am   
Team Member
User avatar

Joined: April 3rd, 2012, 7:53 pm
Posts: 406
Location: Lakeport, MI
stock 49er doing 70+ reving 6800 (listen at the end) 29 years ago
https://www.youtube.com/watch?v=41b49FieyR8


Top
 Profile Send private message WWW  
 PostPosted: August 5th, 2016, 1:10 pm   
Member
User avatar

Joined: September 15th, 2015, 2:35 pm
Posts: 392
Location: Slough, England UK
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.


Top
 Profile Send private message  
 PostPosted: August 5th, 2016, 2:36 pm   
Member

Joined: September 24th, 2012, 7:46 pm
Posts: 355
Location: Lake simcoe
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


Top
 Profile Send private message  
 PostPosted: August 5th, 2016, 4:42 pm   
Team Member

Joined: May 3rd, 2012, 8:25 pm
Posts: 210
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


Top
 Profile Send private message  
 PostPosted: August 5th, 2016, 10:01 pm   
Team Member

Joined: May 2nd, 2012, 11:04 pm
Posts: 167
Location: Burlington, ON
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!

_________________
Jake Elsey


Top
 Profile Send private message  
 PostPosted: August 5th, 2016, 10:13 pm   
Member

Joined: September 24th, 2012, 7:46 pm
Posts: 355
Location: Lake simcoe
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.


Top
 Profile Send private message  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 34 posts ]  Go to page Previous  1, 2, 3, 4  Next

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 7 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  


Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
Style originally created by Volize © 2003 • Redesigned SkyLine by MartectX © 2008 - 2010