Aluminum flex

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Viking Life
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Aluminum flex

Post by Viking Life » Tue Oct 13, 2015 10:32 pm

Anyone using the aluminum automotive flex in place of steel flex for exhaust? Found some and was wondering what pros and cons would be? Obviously a little weight savings but any negative sides?
14ft fberglass ultrlight with a 220 gpu with a whirlwind stump puller prop

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John Fenner
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Re: Aluminum flex

Post by John Fenner » Wed Oct 14, 2015 9:14 am

Never heard of it.
I never finish anyth,,,.

ddriver
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Re: Aluminum flex

Post by ddriver » Thu Oct 15, 2015 10:38 am

temp. would burn it right out.

Viking Life
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Re: Aluminum flex

Post by Viking Life » Thu Oct 15, 2015 12:11 pm

Is the temp that much hotter than automotive?
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Planeguy
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Re: Aluminum flex

Post by Planeguy » Thu Oct 15, 2015 2:01 pm

You could check temp at the end of the header either by installing an EGT probe that far out or run it up until it is good and hot and using an infrared temperature sensor where you want to make the connection.

Afflicted
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Re: Aluminum flex

Post by Afflicted » Thu Oct 15, 2015 3:19 pm

I'm curious as to y u would be considering aluminum flex? Buy STAINLESS.. and I'm almost positive it will melt, when u run hard the exhaust is super hot. Stainless eventually burns out, aluminum I think would be gone first trip out

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John Fenner
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Re: Aluminum flex

Post by John Fenner » Thu Oct 15, 2015 3:42 pm

Why run flex tubing anyway? I have mufflers inside headers with turnouts.
I never finish anyth,,,.

happy harold
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Re: Aluminum flex

Post by happy harold » Fri Oct 16, 2015 8:12 am

in one of my einstien moments, I built a set of headers out of aluminum. that was 15 tears ago and some of the folks in charlotte county are laughing yet. at the end of a one hour running mostly dry, the pieces of the header were mostly in the bottom of the boat except for what went through the prop. hope this answers you question.

Viking Life
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Re: Aluminum flex

Post by Viking Life » Fri Oct 16, 2015 11:42 am

Thanks guys. Was just looking for all ways to lighten the boat. 2-3 lbs here ,, 2-3 lbs there. It all adds up. But it seems like this is a bad idea. John I'll text you about your muffler idea
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Scarecrow
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Re: Aluminum flex

Post by Scarecrow » Fri Oct 16, 2015 12:36 pm

The old saying is----If you watch the ounces the pounds will take care of themselves. :thumbleft: :rebel:

jeepinocala1111
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Re: Aluminum flex

Post by jeepinocala1111 » Sat Oct 17, 2015 8:07 pm

Aluminum on your exhaust :slap: Stainless is great material and if you take it one more step use solid not flex it sounds much better. If you're trying to save cash most muffler shops can bend some aluminized steel pretty cheap then you can just use a short piece of flex.

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Bonefish
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Re: Aluminum flex

Post by Bonefish » Sun Oct 18, 2015 6:10 pm

John Fenner wrote:Why run flex tubing anyway? I have mufflers inside headers with turnouts.

Because in some parts of Florida FWC writes tickets if exhausts are not run out past or thru the transom of the vessel. :dontknow:

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Re: Aluminum flex

Post by jeepinocala1111 » Sun Oct 18, 2015 9:30 pm

Bonefish wrote:
John Fenner wrote:Why run flex tubing anyway? I have mufflers inside headers with turnouts.

Because in some parts of Florida FWC writes tickets if exhausts are not run out past or thru the transom of the vessel. :dontknow:
Actually yes if you read all vessels exhaust is supposed to be through or past the transom but I believe that was cause of inboard explosions. Mufflers are not designed to be mounted to the headers anyway.

Gary S
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Re: Aluminum flex

Post by Gary S » Mon Oct 19, 2015 5:16 am

jeepinocala1111 wrote:
Bonefish wrote:
John Fenner wrote:Why run flex tubing anyway? I have mufflers inside headers with turnouts.

Because in some parts of Florida FWC writes tickets if exhausts are not run out past or thru the transom of the vessel. :dontknow:
. Mufflers are not designed to be mounted to the headers anyway.


I believe Norman would disagree with you.

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Re: Aluminum flex

Post by jeepinocala1111 » Mon Oct 19, 2015 6:32 pm

I am sure there are plenty of people who think mufflers were made to be put on headers but they weren't not to do the actual job of a muffler lets say you do find a company saying it's fine to do that why or who would want that extra weight directly on a header? All around just a bad choice and actually thinking they would do their job with exhaust flames going in them. But hey who cares until the loud ass noise from not doing an actual muffler shuts us all down just not a good choice. :slap:

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