Alfa Romeo ONLY please!
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PietereQ
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Re: Project 2 : front mount SA GTV 3.0 - Sei diff

Post by PietereQ »

Haha the joys of side exhaust; sounds good, looks good, makes working on the car much easier... there always has to be a catch doesn't it? :D
Over here we have this simple trick if you are on the verge of failing the noise test. A push - on 90 degree tip that directs the exhaust to the ground. It really makes a difference and saved the day on the last trackday was taking part in. Got flagged for noise levels, installed these, and could continue tracking for the rest of the day without issues. Without these the car was making around 97dB @3,5K rpm. I know it kinda looks like W123 diesel with these on, but hey, small price to pay, and it takes like 30 seconds to install. The tips are secured with hex screws, more as a precaution, since its a tight fit.
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Zamani
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Re: Project 2 : front mount SA GTV 3.0 - Sei diff

Post by Zamani »

MD sometimes has good ideas…. Sometimes……split the exhaust to both sides. I’m guessing the sound meter is on one side only. The tip has to shrink to 2”. Pieter’s mod also works. Either way I’m Pretty sure with these 2 mods you will pass 100db easily.
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KevinR
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Re: Project 2 : front mount SA GTV 3.0 - Sei diff

Post by KevinR »

Hi Pieter , I would have thought deflecting noise into tarmac could amplify it. Not sure why I thought that as it could result in destructive interference .. .. noise reduction . I understood the exhaust on the 155 DTM were turned up to reduce noise and keep the power they achieved .
I have bought my second box for the other side exit.
Zamani .. I will do both mods .. and turn tips down !
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Re: Project 2 : front mount SA GTV 3.0 - Sei diff

Post by KevinR »

Hi MD, so making plan for noisy tracks to bolt on another side exit . Currently under construction!
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Zamani
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Re: Project 2 : front mount SA GTV 3.0 - Sei diff

Post by Zamani »

Kev,

If this doesn’t work, Reduce the size of the outlet. Since you have a total of 3 outlets (2 outlet on passenger’s, and 1 on driver’s) shrinking it to 2” at the tip shouldn’t have an impact on power but will have a good reduction in noise level.
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MD
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Re: Project 2 : front mount SA GTV 3.0 - Sei diff

Post by MD »

Kevin,
Stop. STOP. SSSSSTTTOOOPPP !!!
You got the concept all arse about face.
The idea is:-
Take the left bank left with a larger muffler only.
Take the right bank with a larger muffler only.
DO NOT COMBINE ANYTHING.

The idea being that you distribute the noise to two locations and not concentrate it into one area for the microphone to pick it up. Noise dispersal is the idea.
Pointing the outlet DOWN may absorb a tiny amount of energy into the ground. Don't count on it but it wont hurt.

What you are showing that you are about to do is going to make 3/5ths of fuck all difference.
Transaxle Alfas Haul More Arse
KevinR
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Re: Project 2 : front mount SA GTV 3.0 - Sei diff

Post by KevinR »

Right got it Md , I will put a potato into the one exit pipe . Normally I save this potato for my budgie smugglers ! The old trick you taught me :)
I will have a blanking gasket which i will use to switch banks ie .. one to left and one to right . This will separate it totally .
Will keep you posted .
You know you never mentioned the the potato was supposed to go in front with the budgie smugglers !
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MD
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Re: Project 2 : front mount SA GTV 3.0 - Sei diff

Post by MD »

Good luck with the fish and chips.
Transaxle Alfas Haul More Arse
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