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      11-28-2019, 01:56 PM   #1
Zambiniftm
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SEEKING ADVICE: Previous Owner Welded Cats Into Akra Evo X Pipe



Hello All,

I need some help here! The previous owner of my car WELDED primary cats BACK into a full akra evo exhaust system (could have easily been a slip-on fitment.. but no lol) in order to pass OH emissions. No idea who the PO is, only going off of the carfax.



The problem with the way this was done, is I have no idea what these link pipes are, but they don't appear to be stock pipes because the driver's side pipe is not crushed in one spot. The cats are simple pinch-weld construction, so theyre probably generic off the shelf cats... but they dont appear to be stock cats either! Also, it doesnt look like the akra evo link pipes have been modded because the welded in section does not feature the small H-pipe that the akra setup has in front of the secondary cats, and the worst part- there are more aggressive, and more numerous bends in the pipes- making me think that this setup is likely making LESS HP than stock, since this area is extremely flow-sensitive.



I am weighing my options as to how to return the modded X-pipe and Link pipes to their original state- with flow-optimized Link Pipes and NO primary cats, because racecar. This is difficult because I cannot simply have the cats cut out and test pipes welded in, because of the numerous and aggressive bends in the link pipes- they probably flow horribly even without cats. I know a lot of engineering and testing went into the specific shape of the original akra link pipes, and I want those horsepressures back!!



So here are my thoughts and questions moving forward- should I:

A) Contact akrapovic to see if they will send the link pipes alone? Drawbacks are going to be astronomical price, and the possibility that they will not sell these components alone

B) Buy an akrapovic X Pipe with link pipes, then sell the incomplete unit from my car?

C) Get another set of catless test pipes from another manufacturer and hope they actually mate up to the akra X Pipe? I'm guessing the pipes are bent and cut in different places, and are not plug and play between different manufacturers. AM I WRONG THOUGH? because this would be great.

D) Have someone custom fab new link pipes with o2 bungs and attempt to duplicate the shape of the original akra link pipes? I would always know in the back of my mind in this case that the most HP-sensitive area in the whole exhaust system is a complete shot in the dark in terms of flow. This would keep me awake at night lol..


Thanks for your consideration and advice. If anyone is willing to part with just the link pipes from an akra system, PLEASE LET ME KNOW! Located
in the Detroit Metro area, if anyone has shop recommendations!

-Aaron
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      11-28-2019, 02:09 PM   #2
SAMM3Y
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B is your best option. Find a used one, they come around. Having one fab'd would be hard because titanium is expensive and bending it is tough. Like you said, the right bends are important in that area. I guess you could buy a ss catless x pipe and rob the section 1 but sounds like you're a purist..

If you want to explore fabricating one you could price out the titanium at ticon.com. You need 2.375" tubing. You can buy pie cuts and mandrels but it will cost you a lot for materials and labor for tig if you can't diy
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      11-28-2019, 02:34 PM   #3
Zambiniftm
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Hey, thank you for the reply!

I'm not purist to the extent that I'm opposed to using SS over titanium. (definitely no akra fanboy either.) The weight savings to the tailpipes are probably enough to call link pipe weight difference negligible. Exhaust flow efficiency is my main focus.

My only concern there is the possibility that the SS link pipes will not mate to the exact width and location at the ends of the akra X-pipe. I have zero experience in fitting mis-matched exhaust systems here. Is this a pretty standard kiss-off point for all aftermarket exhausts?

Thanks again!
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      12-09-2019, 08:31 PM   #4
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From first hand experience, fabricating titanium and salvaging the work here takes more than just the cost of materials. I had a akra exhaust salvaged back to functional form and it ended up costing me quite a bit (titanium premium)

I talked with a bunch of exhaust shops and none would recommend welding stainless to titanium, the only sure way of salvaging the job right now would be to flange titanium pipes to stainless, might be difficult depending on the clearance

A) not possible - when I was salvaging my exhaust I asked about this and it just isn't possible without astronomical costs. (You're basically buying a new system)

C) wouldn't be plug and play, I don't know of any titanium test pipes that would mate up to this, from my understanding akra widths and lengths are also different. Even if you do add in the test pipes you'll be missing the h pipe

D) wouldn't suggest something that keeps you up at night, also cost of this will be likely higher than C, which i assume would be pretty high already

I think B will be your best option - I might be interested in purchasing this as an art piece if you do decide to go down this route
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      12-10-2019, 11:00 PM   #5
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Disappointing to see such artwork butchered.
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