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AIRCRAFT GEARBOX PERFORMANCE

DAVE C

Well-known member
WILL BE NEEDING NEW CAGE/RIGGING IN FALL AND THINKING ABOUT TRYING REDUCTION ON STRAIGHT VALVE 0540 LYCOMING ON 12 BY 8 DECKOVER IN FALL. IM WORRIED ABOUT LOSING SPORTINESS IN BOAT DUE TO LAG IN GEAR BOX AS WELL AS BEING ABLE TO RUN TIGHT TRAILS.ANYBODY HAVE ANY ANY IDEAS OR EXPERIANCE WITH THIS SET UP?? THANKS IN ADVANCE......... :old_glory:
 

pontoon outlaw

Well-known member
:scratch: You have a Lycoming just go with the Lycoming box 1:51 to 1 no lag at all, I use that same box on my Cad 507 on a 12 ft hull and it is night and day from direct drive I wouldn't have it any other way... JMO I run the tree line all the time and it handles great in tight places we go where the big boys can't or won't :lol:
 

Tony480

Well-known member
If your staying with the same hull you have now. How will that effect you running tight trails? A gear box won't change nothing.
 

skinny99

Well-known member
Every gearbox A/C boat I see runs good. More power is usually a good thing.

The concern I would have is on a 12' boat you will need to put some thought into your rigging. The gearbox adds some overall
length to the drivetrain. If you slide the seat stand forward to make room the boat may not handle as well as it did before. You will already
be sliding the engine forward.
 

getchasumairboats

Well-known member
If you wanna call me i will be more than glad to talk to you. We have two of them. I will not post any info here its a waste just turns into a pis sing match. I can pm my number if you want.
 

farmboy

Well-known member
getchasumairboats said:
If you wanna call me i will be more than glad to talk to you. We have two of them. I will not post any info here its a waste just turns into a pis sing match. I can pm my number if you want.
Amen to that... I tried that crap this time last week about prop pitch differences and ended up with 10PM's being called a lie. That will be the end of that :salute:
 

Quick Draw

Well-known member
Don't worry about tight trails cause of a gearbox cause when you add a gear you can make new ones.
Farm, I was wondering what happen to that post about that but u pretty explained it now.
 

todd glover

Well-known member
I've seen people add a gearbox and wondered why the motors that come with them also turn more rpm has anyone ever done a before and after to see the difference thrust test speed etc just wonder if it really does anything on a motor that wasn't designed for one
 

gyrocopter582

Well-known member
Amen to that... I tried that crap this time last week about prop pitch differences and ended up with 10PM's being called a lie. That will be the end of that :salute:[/quote]

BAWHAHAHA!! SAY it isn't so farmboy!!

I rest my case... :roll:
 

Dglover

Well-known member
:usa: Without boring you. In a nut shell a gearbox basically gives a engine with small balls BIG BALLS. In turn being able to turn a big prop with some big pitch. Prime example look what it does for a car engine gives them the ability to turn some huge props otherwise would never happen without it's help. :lol: :lol: :lol: :lol: :usa: :usa: :usa: :usa:
 

Bruce

Well-known member
if you do it you had better plan on building a shroud higher rpms mean higher cyl head temps and a sv 540 has a small area of cooling fins vs an angle valve just some food for thought
 

bbstimey

Well-known member
probably will need a cam change as well, strait valve makes power at 2700 rpms
you want to turn 3300 to 3500 for best results.
 

Southern Style

Well-known member
Ted, thats what I was thinking.. Do you have to do internal work on them to get them to work?? I hate having to slide the seat and engine package forward, but if it is a "bolt on" application, seems the best way to get extra power.. Minus having to buy another prop plus the gear box.. Would definately have to price a 520 kit vs a gearbox and a new prop to see which one would be the least expensive..
 

Southern Style

Well-known member
Bruce, I am trying to figure out from a base measurement of a stock (lets say) 470 Continental to a complete set up with a gear box installed, the actual added inches.. Seeing if the finished product would be feasable on a standard rig, like the original posters... Or would you have to actually get a foot longer hull due to the added equipment for the purpose of making sure the weight is distributed properly.. We know how a boat runs with everything shoved on the nose.. LOL
 

todd glover

Well-known member
gyrocopter582 said:
Amen to that... I tried that crap this time last week about prop pitch differences and ended up with 10PM's being called a lie. That will be the end of that :salute:

BAWHAHAHA!! SAY it isn't so farmboy!!

I rest my case... :roll:[/quote]
I'm not sure why you reposted this I was just asking a question but if you have a problem feel free to pm me ill be your huckleberry
 
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