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Discussion Starter #1
I don't want to thread-jack, so started this thread....!

At what level of power do you dump the Akrapovic...?

Adam kindly posted a graph on tube diameter etc...but I am not able to calculate the diameter of my exhaust ie one pipe in to two pipes through to four at the back.....I am lost already...

So has anyone got a idea of Maximum BHP for said system....?

Daniel...:confused:
 

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David Yu asked that question of the Akrapovic engineers here and was told,
Main piping is 86mm [inside diameter]. Not sure what power it is capable of handling, but Steve's mega Alpha 9 build started with an Akrapovic, but not sure if it's going to stay on.

I asked last year and Akrapovic's engineers said it would easily handle at least 800hp but wouldn't speculate at what point it could become a restriction.

Certainly as far as titanium systems go, I would guess it was one of the very best as it is unique in combining that free flowing design AND perfect mandrel bends (very difficult to do in ti).
My then stage 2 car gained 24hp peak power just by bolting it on, and that was compared to the non-resonated Milltek y-pipe I had on before. Area under the curve and spool rpm was massively improved too.
For ~850 the Akra won't exactly be the first thing on the list that needs attention, if at all.
102mm are shown to provide HP gains on the dyno; but if they are stainless, the Y-pipe alone weighs more than the complete Akrapovic so not quite the step forward the paper figures might have you believe. 102mm titanium, if the quality is there should deliver.

Protegimus
 

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I think the best thing will be dyno the Akrapovic....

Same car same day re dyno.. But with the 102mm

Then it's hard fact...

I just feel sure this must have been tested or proved already..

Dan..
 

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I seem to remember the guys in the US saying that with 90mm pipe work 900-950 hp was your lot, literally wouldn't flow anymore. But it can start to become a restriction before that. Ie, you'll notice a difference, turbos won't have to work as hard.
 

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Discussion Starter #6
It's the balance of quality and sound, that it can't find elsewhere...

I am happy to stick at 850 give or take, so long as the akra's not harming the engine...

Dan
 

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I would stick with it, at the 850 level its very light and sounds amazing.
 

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Hi dan up until this last upgrade I had no issues and that was about 8/850 now I have over 900 I was told by svm it was holding the engine back so I have had to go for there 102 system so I have the system sitting in my garage waiting to go up for sale , I wish I could of kept the akropovic the sound was the best in my opinion ,what spec are you going for I would say 8/850 is plenty for the road mine now is a bit to much for me anyway .andy
 

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Discussion Starter #12
Hi dan up until this last upgrade I had no issues and that was about 8/850 now I have over 900 I was told by svm it was holding the engine back so I have had to go for there 102 system so I have the system sitting in my garage waiting to go up for sale , I wish I could of kept the akropovic the sound was the best in my opinion ,what spec are you going for I would say 8/850 is plenty for the road mine now is a bit to much for me anyway .andy
It's never to much..!

My Akra is still up for sale,only had one enquiry,it's a bit pricy for most I guess.

If I get any interest I will put them on to you...as I am keeping mine...:clap:

Dan....
 

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nothing sounds like an akra. No matter if bike, beamer or GT-R ;)

I think as Daniel said, everything 800+ Needs more diameter.
 

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i suggest getting akra to develop a larger system that brings the same quality and amazing sound but offer more power and larger tubing for higher power builds who are looking for quality and amazing sound.

cant go wrong with this system otherwise, its a work of art also.
 

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Please note that the amazing sounds changes when you add downpipes which will certainly be the case at 850.

It gets a lot louder, still makes a great noise but the volume was too much for me, the power was not the reason I changed.
 

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Discussion Starter #17
Please note that the amazing sounds changes when you add downpipes which will certainly be the case at 850.

It gets a lot louder, still makes a great noise but the volume was too much for me, the power was not the reason I changed.
Thank God...! Sounded awesome outside, ie if my bird overtook me...

But the sound inside was lame..

I need a bit of noise in the GT-R to make up for the M3 silence..

Dan...:clap:
 
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