Hp Loss Through A Full Exhaust?

FILT166

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thinking of getting a turbo kit but with a full exhaust setup On my gen 2
How much hp loss would there be on a stg 1 or any other kit?
Anyone running the full exhaust on there's?
 
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I am running a full exhaust from day one as i and especially my neighbours do not like the noise.
The power loss must be around ~20-25 bhp, instead of a calculated 300 hp i get around 280-275.
Have in mind that my exhaust is quieter than stock and i think it uses 2.5 inch stainless steel tubes (or is it 2'' ?), i shall check and come back.
Btw i love the noise that my bike makes as it is a nice thunder deep sound but only up to 5000 rpm,
after that the sound just goes away completely and the only sound i hear is the one coming from the engine's internals.
Here is a picture of the exhaust among other things:
https://www.hayabusa.org/forum/threads/finally-i-went-turbo.182536/page-2
Chris
 
That's quite a bit of hp loss there.
That dyno run was through the full exhaust?
I wonder how much hp loss there would be on a stg 1 kit making a lot less power on a gen 2.
 
If it's an Rcc kit, you can expect to see zero power loss up to 500hp.

When you're ready give me a call or shoot me a message and we can give you our hayabusa.org members discount on an Rcc kit.
 
That's quite a bit of hp loss there.
That dyno run was through the full exhaust?
I wonder how much hp loss there would be on a stg 1 kit making a lot less power on a gen 2.
Yes the bike was measured with the full exhaust.
It depends on how quiet you want the bike, from what i have learned 3'' exhaust tubing diameter is great but will not fit under the fairing easily, 2.5'' can fit and it is acceptable.
The final stage (silencer) is of a straight through type and i chose it based on the sound i wanted the bike to make.
Chris
 
Unless the muffler is custom made like RCC they are usually much less than 2.5id and choke the turbo big time
I just measured my exhaust and it is 2.5''
I am sure that a 3 inch pipe will not fit under the fairing without surgery but it is far better than 2.5 inch.
Maybe someone can manufacture a 3 inch oval tube for better fit under the fairing.
Chris
 
3 inch is overkill with your turbo , 2.5 pipe with a 2.5 bore straight through muffler should be all it needs
 
Our mufflers are all 2.5" I.D. and have show no hp loss to 500hp, many tests performed with our mufflers compared to dump pipes, and different air filter combinations, and less than 5 hp variance on the dyno, and when making 500hp a 5 hp difference is minimal
 
I am sure that you are correct after so many measurements so maybe i am running too rich or the muffler i use is too restrictive because 12 psi only produce 270-280 hp on my bike (which is fine with me, i don't need more).
BTW i use the MCxpress Mcx400 turbo kit and when it was measured i had ~9 to 1 compression
with the use of a thicker base gasket, now i use turbo pistons but i haven't tried to measure the hp output yet but the bike feels a little stronger mid range and weaker than before (or maybe should i say smoother?) in the upper rpm range.
Chris
 
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Hendrixgr your using the tdo5 right ?
from the SAU forum at 15 psi
TDO5H-16G-7CM2 505 CFM
TDO5H-16G-10CM2 505 CFM

TD05-16G (small) 345-365hp @ 22 psi

TD06-16G (large) 365-385hp @ 22 psi

I think your pretty much on target for your turbo , starts making good positive pressure fairly early in the rpm range , limits top end potential a little and can boost creep at high rpm
 
Hendrixgr your using the tdo5 right ?
from the SAU forum at 15 psi
TDO5H-16G-7CM2 505 CFM
TDO5H-16G-10CM2 505 CFM

TD05-16G (small) 345-365hp @ 22 psi

TD06-16G (large) 365-385hp @ 22 psi

I think your pretty much on target for your turbo , starts making good positive pressure fairly early in the rpm range , limits top end potential a little and can boost creep at high rpm
Hi and thank you for your valuable information!
I think you may be right except that i use the slightly bigger mcx400 turbo which i think a modified KKK 28 or similar and i have zero boost creep with its external wastegate.
Other than that it sure looks like it looses top end power like you said.
Here is a relevant page: http://www.mcxpressturbos.com/suzuki_hayabusa_motorcycle_turbo.html
Look at the middle of the page for the turbo change from 16G to 3K.
Top power is 400hp which i think is way out of its efficiency range
Chris
 
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Just an idea, but is it possible to run the full exhaust as a daily to keep it quiet and connect a cut out/dump pipe that you can open electronically like a lot of cars do?
It'll dump on the left side of the bike.
 
So what I'm gathering from this is that a full exhaust system added to a stock bike increases hp but actually reduces hp on a turbo if the turbo is added?
 
So what I'm gathering from this is that a full exhaust system added to a stock bike increases hp but actually reduces hp on a turbo if the turbo is added?
A full exhaust on a n/a motor is less restrictive than stock, meaning you can gain power when you tune for it. On a turbo bike a full exhaust that is more restrictive than a dump pipe will reduce power. RCC have engineered around that issue with a full exhaust which doesn't restrict the flow. They've tested it up to 500 hp.
 
You'll lose 50hp....lol,joking

I have a turbo exhaust off a nissan 240sx...it comes out at turbo,at 3" .... a foot away,it has a 3 bolt connector,the goes from 3" to 2.5" afew feet away to muffler.....right now I'm just using the 3" section as a dump pipe....but I might add the rest and a custom muffler later....not many neighbors around me,and once I get past 20mph,it's not loud...turbo muffles sound...and I don't do "lots" of miles
 
A full exhaust on a n/a motor is less restrictive than stock, meaning you can gain power when you tune for it. On a turbo bike a full exhaust that is more restrictive than a dump pipe will reduce power. RCC have engineered around that issue with a full exhaust which doesn't restrict the flow. They've tested it up to 500 hp.
I see, thank you for the clarification
 
I had a full Exhaust made by Eric at DAS out of my Akrapovic pipe
Old turbo setup with a FMU power flatlined at ~353 more boost was not really adding HP
in the middle of the dyno day I sawzalled the pipe off and the bike gained 35 hp
pipe was small I can measure later if it matters but someone must know Akra pipe size @GIXERHP ?
 
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