Boating at 7000' Elevation

[88Checkmate]

I have a 25' Shockwave with a 500 EFI, most of my boating is at a lake that is at 7000' elevation, the engine runs fine except that I am only able to get about 4500 rpm's at WOT with a 24" bravo 1 prop. at Havasu I can run a 25" prop and get 5100 rpm's.

would changing out the throttle body to something like a Hardin 1000 cfm improve performance to get more air to the intake?

or any other suggestions?

Thanks

 

[Done-it-again]

Have you tried a 22 pitch prop? You should be able to get more RPM’s out of it.

 

[mash on it]

At 7000 ft, your 500 is ~105 hp down.

So you can prop it down or add hp.

Elevation likes forced induction.
(More oxygen/air and fuel, more horsepower...)

A larger throttle body may give you 10 to 15 hp, but over a hundred horsepower is unrealistic.

Dan'l

 

[wsuwrhr]

Yep,

Dual hairdryers, or a supercharger is the only thing to fix low 02 content.

Compressing air is the only way to add air that just isn't there at high altitude.

Brian

At 7000 ft, your 500 is ~105 hp down.

So you can prop it down or add hp.

Elevation likes forced induction.
(More oxygen/air and fuel, more horsepower...)

A larger throttle body may give you 10 to 15 hp, but over a hundred horsepower is unrealistic.

Dan'l

 

[Trash]

I have a 25' Shockwave with a 500 EFI, most of my boating is at a lake that is at 7000' elevation, the engine runs fine except that I am only able to get about 4500 rpm's at WOT with a 24" bravo 1 prop. at Havasu I can run a 25" prop and get 5100 rpm's.

would changing out the throttle body to something like a Hardin 1000 cfm improve performance to get more air to the intake?

or any other suggestions?

Thanks

You need to put a smaller pitch prop on it. I'd go down at least 2" in pitch.

 

[88Checkmate]

Thanks for the input.