Flex Joints, Stay Stiff or Flex ?

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CFK
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Joined: Mon Oct 25, 2010 6:28 pm
Location: Vancouver, B.C. Canada.

Flex Joints, Stay Stiff or Flex ?

Post by CFK »

So I will be installing 3" TBE soon and the ? is whether to install a flex joint or not ?

I know there is not as much of an issue with the boxer motor and vibration but is it still a good idea to have one anyway ? Has anybody feel that they have cracked there downpipe due to not having one ?

I just purchased a Megan WRX Bellmouth downpipe and was thinking of moving the mounting tab so it will bolt up to the tranny as well to stabilize it, then installing a flex joint just downstream of the DP flange.

I think it's a good idea, necessary. Not sure ? I guess Group N motor and tranny mounts would definitely help as well.

Opinions would be appreciated, Thanks. :-)
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kimokalihi
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Re: Flex Joints, Stay Stiff or Flex ?

Post by kimokalihi »

Mine doesn't have one and I haven't seen many people who do.
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CFK
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Location: Vancouver, B.C. Canada.

Re: Flex Joints, Stay Stiff or Flex ?

Post by CFK »

That's what I thought, but after breaking a $550 Tri-Y header on my Jetta I was gonna try and do things right this time. Although that was a stupid ball and socket end that I had to overtighten to seal which therefore collapsed eventually :smt013

Then when I called the local parts place for a High flow cat qoute they said there was 2 different flex joints, one for NA & one for a boosted car which was a stronger unit to withstand hogher temps. Obviously being more, priced at $75 I just don't think it's worth it if not necessary.

Although I might just order a cheaper one I found for $35 off 034 Motorsport when I order the extremely hard to find " Tight" Radius 2" silicone elbow for my TMIC re-install.
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kimokalihi
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Re: Flex Joints, Stay Stiff or Flex ?

Post by kimokalihi »

I wouldn't bother with it. Waste of money. My setup is 3" bellmouth which bolts to a solid one piece 3" exhaust all the way back.
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CFK
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Posts: 379
Joined: Mon Oct 25, 2010 6:28 pm
Location: Vancouver, B.C. Canada.

Re: Flex Joints, Stay Stiff or Flex ?

Post by CFK »

Alright, what about the proper tranny mount, does yours bold up ? or forget about that, just bolted to the turbo and hangers on the rest ? Possibly some extended hangers maybe, depending on my rocket rally exhaust fitment.
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kimokalihi
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Re: Flex Joints, Stay Stiff or Flex ?

Post by kimokalihi »

I'm almost positive mine is just hanging on the hangers. You're not going to crack anything. The header is bolted to the up pipe which is bolted to the turbo and the downpipe is bolted to the turbo as well and the turbo is bolted to the block/head. Bolting it to the trans would be a good idea but I'm not worried about mine.
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CFK
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Posts: 379
Joined: Mon Oct 25, 2010 6:28 pm
Location: Vancouver, B.C. Canada.

Re: Flex Joints, Stay Stiff or Flex ?

Post by CFK »

Ya, was just worried about the side to side when going over bumps. Maybe I should have gotten one with a cast bellmouth, the stainless seems pretty thin. For the sake of quickly cutting and tacking a bracket I think I will. Probably won't bother with the flex joint then.

Thanks for the help :smt045
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