Is a Milltek Catback worth it?
- Thread starter HeronS3
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HeronS3
Registered User
Sorry mate I literally have no idea what this means. Total newbie when it comes to this sort of stuff.
The exhaust is in 2 parts, the first joins the turbo and has the pre cat and cat in it. This is called the down pipe and runs from the turbo to just after the main cat.
The rest of the exhaust is called a cat back, because it runs from the cat to the back of the car, and includes the back box.
The main restriction is the narrow down pipe, and the pre cat and main cat installed in it. Significant gains can be had by replacing this particularly restrictive pipe. It will spool easier and flow much better. I believe (could be wrong) that the stock cat back isn't that restrictive and would only start to get in the way at higher rpm, in higher states of tune. When it's capacity to flow easily is reached and it starts to generate significant back pressure.
The rest of the exhaust is called a cat back, because it runs from the cat to the back of the car, and includes the back box.
The main restriction is the narrow down pipe, and the pre cat and main cat installed in it. Significant gains can be had by replacing this particularly restrictive pipe. It will spool easier and flow much better. I believe (could be wrong) that the stock cat back isn't that restrictive and would only start to get in the way at higher rpm, in higher states of tune. When it's capacity to flow easily is reached and it starts to generate significant back pressure.
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The exhaust is in 2 parts, the first joins the turbo and has the pre cat and cat in it. This is called the down pipe and runs from the turbo to just after the main cat.
The rest of the exhaust is called a cat back, because it runs from the cat to the back of the car, and includes the back box.
The main restriction is the narrow down pipe, and the pre cat and main cat installed in it. Significant gains can be had by replacing this particularly restrictive pipe. It will spool easier and flow much better. I believe (could be wrong) that the stock cat back isn't that restrictive and would only start to get in the way at higher rpm, in higher states of tune. When it's capacity to flow easily is reached and it starts to generate significant back pressure.
An excellent explanation, the only thing that I would add is that the replacement downpipe would either have a less restrictive sports cat than the standard down pipe that has 2x cats. You can have no cat at all. This is called a decat pipe but this would cause you problems at MOT time.
My son has just a catback on his MK 7 Golf R and no replacement downpipe. It made virtually no difference when he had the power checked on a rolling road but it does make more noise.
You can have a catback without a remap but if you have a down pipe or full exhaust you need a remap as it gives you warning lights on the dashboard.
