Supercharger boost pressure

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Dirtman
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Supercharger boost pressure

Postby Dirtman » Tue Dec 29, 2015 8:24 pm

Can anyone tell me the normal range for boost pressure on a supercharged Lycoming
IO520 on a 12"6" Lazer with a 72" Q #20814
Build in progress: 14x7'9" JB w/ GSO540 &80" Razor

jerryncypret
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Re: Supercharger boost pressure

Postby jerryncypret » Wed Dec 30, 2015 6:38 am

I've seen about 15 to 18 psi

Quick Draw
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Re: Supercharger boost pressure

Postby Quick Draw » Wed Dec 30, 2015 11:33 am

All of the ones I've ever seen was 14 to 15 psi at 3400 rpm on a gso. I drove Farmboy's boat a couple months ago and his was laying a 20psi gauge in the corner. I don't know if his gauge is broke and he didn't have a tach so I don't know at what rpm.

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farmboy
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Re: Supercharger boost pressure

Postby farmboy » Wed Dec 30, 2015 1:26 pm

My gso is 15psi at 3400 rpm's.
14ft JB Hull,Lycoming GSO480 w/water-meth injection,Sensenich 3-blade "R",ButtRaxx seats,B&S Trailer.

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farmboy
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Re: Supercharger boost pressure

Postby farmboy » Wed Dec 30, 2015 1:28 pm

Quick Draw wrote:All of the ones I've ever seen was 14 to 15 psi at 3400 rpm on a gso. I drove Farmboy's boat a couple months ago and his was laying a 20psi gauge in the corner. I don't know if his gauge is broke and he didn't have a tach so I don't know at what rpm.

Gauge must be broke... :scratch:
14ft JB Hull,Lycoming GSO480 w/water-meth injection,Sensenich 3-blade "R",ButtRaxx seats,B&S Trailer.

Member of Glades Airboat & Buggy Association / Kissimmee River Valley Sportsman Association

SkinnerBack
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Re: Supercharger boost pressure

Postby SkinnerBack » Wed Dec 30, 2015 3:16 pm

I think Farmboy is hiding something tricks up his sleeve!!! Lol

Dirtman
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Re: Supercharger boost pressure

Postby Dirtman » Wed Dec 30, 2015 10:35 pm

Thanks for the replies guys, was told several different things by guys who didn't own a GSO engine but had a friend of a friend kind of thing. Glad to get some good info. Hopefully the boat will be ready for the Broward show its been a long time coming
IO520 on a 12"6" Lazer with a 72" Q #20814
Build in progress: 14x7'9" JB w/ GSO540 &80" Razor

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farmboy
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Re: Supercharger boost pressure

Postby farmboy » Thu Dec 31, 2015 6:20 am

SkinnerBack wrote:I think Farmboy is hiding something tricks up his sleeve!!! Lol

Not me :headbang: :lol:
14ft JB Hull,Lycoming GSO480 w/water-meth injection,Sensenich 3-blade "R",ButtRaxx seats,B&S Trailer.

Member of Glades Airboat & Buggy Association / Kissimmee River Valley Sportsman Association

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farmboy
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Re: Supercharger boost pressure

Postby farmboy » Thu Dec 31, 2015 6:29 am

Dirtman wrote:Thanks for the replies guys, was told several different things by guys who didn't own a GSO engine but had a friend of a friend kind of thing. Glad to get some good info. Hopefully the boat will be ready for the Broward show its been a long time coming

RPM's changes everything... If every motor turned 3400 every one should make 14 to 15 psi cause there all made with the same parts unless the charger has had work done to it...
14ft JB Hull,Lycoming GSO480 w/water-meth injection,Sensenich 3-blade "R",ButtRaxx seats,B&S Trailer.

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444kyle
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Re: Supercharger boost pressure

Postby 444kyle » Wed Jan 06, 2016 10:02 am

where do yall pull the psi from. Hook a gauge to the boost ref. line for the carb?
14ft JB Hull,Lycoming GSO480,10 blade warp drive

Dirtman
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Re: Supercharger boost pressure

Postby Dirtman » Wed Jan 06, 2016 6:39 pm

Kyle hopefully Kevin will see this and chime in. I was intending on running the boost pressure gauge off the port at the bottom of the piping running from the supercharger to the plenum the intake tubes come out of
IO520 on a 12"6" Lazer with a 72" Q #20814
Build in progress: 14x7'9" JB w/ GSO540 &80" Razor

TIGO541
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Re: Supercharger boost pressure

Postby TIGO541 » Wed Jan 06, 2016 8:22 pm

Yes there is a 1/8npt in the intake to hook the gauge to. Some have one on both sides
13-6x7-6 Hamant Ultra-lite,Custom TIG Stainless rigging,1.7 Rotator,Supercharged 480,Electronic Ignition,80 inch 3BLD R,B&S trailer

TIGO541
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Re: Supercharger boost pressure

Postby TIGO541 » Wed Jan 06, 2016 8:23 pm

444kyle wrote:where do yall pull the psi from. Hook a gauge to the boost ref. line for the carb?

This you can do also yes
13-6x7-6 Hamant Ultra-lite,Custom TIG Stainless rigging,1.7 Rotator,Supercharged 480,Electronic Ignition,80 inch 3BLD R,B&S trailer

12PSI
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Re: Supercharger boost pressure

Postby 12PSI » Thu Jan 07, 2016 9:28 am

Before I had enough prop to hold it back, my 540 would peg a 25lb gauge.


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