540 Headers...

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rick
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540 Headers...

Post by rick »

Just curious about header tubing size. The used 540 I bought for the old boat that I'm re-doing only has 1 3/4" diameter tubing for headers. Is that biggest enough?

If not, I'm gonna change headers and was thinking about those Norman Clay headers with the muffler welded on. Any opinions on that would be appreciated too.

Thanks,
Rick
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kwanjangnihm
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Re: 540 Headers...

Post by kwanjangnihm »

Rick this post has good info from Chuck! viewtopic.php?f=47&t=32748

A big concern is which way the exit tips will be pointed. A good friend has a high dollar header set on his 520 that dumped straight back into the prop. He said the exhaust noise bounced back off the prop and into the hull and he hated it. He had turn outs installed which made it much better. On my new build (AV540) I am running mine thru 2.5" stainless magnaflows down and out the back of the boat, behind the back lip of the transom with turn downs. (hope its quieter) Good luck and post some pics of what you decide to go with!

:salute:
He'll cut your throat, baby, stick you in the back, drive off in your Cadillac.
He's more trouble than you think, he'll kill your sugar, leave you in the drink.
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rick
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Re: 540 Headers...

Post by rick »

That's a badass header thread kwan... I searched and didn't come up with that one. I believe if Chuck (RIP) was still alive, I be giving him a call to talk headers.

Possible 20-25 hp gain by spending more on headers on a light boat turns my head and makes me want to do a little more studying.

Rick
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Slidin Gator
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Re: 540 Headers...

Post by Slidin Gator »

I think this quote basically sums it up.
chuckitt@earthlink.net wrote:
Thu Jan 28, 2016 10:04 am
All airboat headers are made to be affordable. They are not designed to make power.
Thanks, Chuck
I have one boat with shorty headers and 2.5" flex into Magnaflows, the other is the 3" shorty with built in resonator blasting onto the prop.

The resonator setup is loud and on my list to change out in the future. If you like to hear the engine, those are the ones. The Magnflow setup is quiet and relatively low cost to implement, it is a world of difference n sound vs. the shorty resonators.

But, neither of these setups are doing me any favors on making power, the shorty headers delete any real potential advantages of power on the exhaust side, it is more about the minimum stuff to get the job done. I have taken note of Chuck's 1.75" x 32" primary and 2.25" collector formula.
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.
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kwanjangnihm
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Re: 540 Headers...

Post by kwanjangnihm »

Hey Rick!
In your other post you mentioned the straight valve 540 had "H" pistons. Do you know what compression ratio that makes and are there any other mods to the motor?
He'll cut your throat, baby, stick you in the back, drive off in your Cadillac.
He's more trouble than you think, he'll kill your sugar, leave you in the drink.
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rick
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Re: 540 Headers...

Post by rick »

Those pistons are 9:1 in the h2ad o-320. Not sure if that figure changes in the 540 cylinder or not.

The only other thing different that I was told is that the motor was built from a turbo or supercharged motor (can't remember which) and should have a little better crank.

I'm no expert so correct me if I say something stupid when it comes to the internals :)

Rick
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Re: 540 Headers...

Post by rick »

Slidin Gator, I keep going back the "If you like to hear the engine, those are the ones" part of your post. I'm getting to be somewhat of an older guy (probably 4th quarter or so lol) and I think what you said set my mind to quit thinking about the no flex pipe option. I'm good with the prop sound and anything extra coming from the motor doesn't really interest me these days.

Main reason I was thinking about it was that slick bottom on my new/old hull and having to pull the rigging off every now & then to replace it. That flex pipe is a pain in the butt to mess around with after it's been on for awhile. Probably just mount the flex pipe to the cage and figure out how to lift everything at the same time. I think I did that with my old Hamant 4 cyl. years ago

Rick
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Re: 540 Headers...

Post by Slidin Gator »

A buddy of mine just got done with a new boat build. He used Norman Clay (Innovative Accessories) headers that look just like my resonators and then 3" flex run out the rear. I do not know if they are resonator or baffled muffler tips, but I was impressed at how quiet the setup is while being compact and clean. Innovative advertises 10 different mufflers, I must have the loudest.
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.
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Raizincane
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Re: 540 Headers...

Post by Raizincane »

Hey Rick If you're still looking for them headers Larry Rowe was selling some like you're wanting, they are pricey but are nice looking. He is located in Christmas 321-460-7072
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Re: 540 Headers...

Post by rick »

Thanks Frankie, but I went ahead & used the headers that I had. Bolted the flex pipe to the cage so I'll be able to lift everything at once when it comes time to redo the slick bottom.

Rick
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