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Discussion Starter · #1 · (Edited)


Solid lines = hp and tq with cutout
Dotted lines = hp and tq before cutout

+80whp!



Running IAG Stage 4 extreme with stock crank + IAG stage 5 heads with Kelford 272s

I chose the PTE 66mm wastegate welded into downpipe over a traditional cutout because it is made of materials that can stand up to exhaust gas heat and offer optimum seal. No failing electric motors or metal valves that don’t seal causing exhaust leaks. The wastegate opens at 15psi boost pressure.

Everyone should definitely do this mod if you want a quiet exhaust without sacrificing power when you get on it!
 

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Wow, very impressive, I might have to try this out this myself. A while ago I was thinking about installing a cutout simply so that I could quiet my car down whenever I needed to (cold starts in my neighborhood, passing cops, etc) as right now my straight pipe often gets me in hot water. 😆

I wonder if it would have significant effects for me at my power level; roughly 325-350 wheel if I had to guess
 

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Discussion Starter · #6 ·
Haha 4” exhaust too deafening for me to drive it everyday :(

A 4” exhaust will spoil quicker but then you can run a lighter spring in the cutout to get it to open earlier :)
 

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Hummm, maybe I'll use the extra Tial 44MM gate that I have and bypass my GESI Cat with it. But My power goals are only about 450Wheel, who knows how much of a bottle neck the cat will be.

The gate looks pretty close to your O2, but I'm guessing you had no issues with it reading correctly?
 

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Discussion Starter · #9 ·
You’ll gain 40whp for it I bet :) cats are notoriously restrictive beyond 400whp

Nope no problems with O2 readings
 

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You’ll gain 40whp for it I bet :) cats are notoriously restrictive beyond 400whp

Nope no problems with O2 readings
I went with a GSport GESI 3" Ultra Cat. Their rated to flow to 500HP with "negligible" restriction and up to 800HP with "acceptable" restriction. I did quite a bit of research on them and they seem to be legit, it was also 400 dollars 😦. But, its not really an option for me not to run one. In reality, yes it'll probably cause a bit of restriction, but they're about the best option around. And if it becomes a huge bottle neck, then I'm glad you made this post!
 

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So im confused, you said that its something if you want a quieter exhaust without sacrificing power. But how lol, its an open dump wastegate off the down pipe :unsure: On top of that, you have your EWG dump tube above it just past the axle.

Makes you wonder what is this mans definition of "quiet exhaust" LoL o_O
 

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Discussion Starter · #12 ·
It’s for the people who think a quiet Subaru at idle with no rumble is slow :)

The car is incredibly liveable cruising on the highway and sitting at lights with the Milltek exhaust, more so than the Corsa I had before. Sounds barely louder than stock driving around normally haha
 

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most other driver just want to get away - heck - there are a lot of people who get out of the way of my Cobb exhaust . . . one of the nicer things about being a little loud . . .
 
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Discussion Starter · #15 ·
Ahhhh forgot you had the milltek on the car. I wonder what the car sounds like when this downpipe wastegate opens up.
Sounds like an open downpipe and it drowns out the EWG haha
 

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Discussion Starter · #17 ·
Yup absolutely, you’ll see gains no matter where it is mounted :)
 
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