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Exhaust Question.

Burniehoon

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I was just wondering if a 2 1/2 inch exhaust will bolt straight on to the stock cat?

Also any comments about the ones off EBay i thought they couldn't be much different to any others but i may be wrong so i thought id ask.

Thanks in advance
Jiff.
 

JA2Z

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Hi,

A 2 1/2 inch system should bolt straight on as the pipe may be larger but the joining plate will be the same size as you stock Cat.

With exhausts there is a lot of misconceptions when it comes to street legal systems:

Extremely high performance systems may give Professional racers that 10th of a second they need to win a race. But because street systems a restricted by length, pollution and noise level i believe that it is a severe waste of money to spend thousands of $$ on a system that may give you that .5Kw extra.


The Main thing you want to think about it whether the ehxaust system is 'mandrel bent' or not. 'Mandrel bent' means that the bends in the pipe are not compressed to allow for the compression and stretching of the bend, instead for e.g. the full 2.5" diameter will be maintained:

This is an exhaust bend that is NOT mandrel bent:

As you can see the actual usable diameter of this pipe is smaller than what ends of the pipe are, this pipe is not a truely rated size pipe.

This is an exhaust bend that IS mandrel bent:

As you can see this bend allows the full diameter of the pipe to be used, therefore is far better AND a true rated size exhaust.

Price vs Performance:
The other thing to note in most Cat back exhaust systems is the quality of the mufflers that are in the system (if any.) Most Cat back systems range from: $300 - $2000+, Basically the more you spend (to a point) the better flow (i.e. power/efficency) and better the sound the mufflers in them will produce.

Size:
In relation to size: There is such a thing as too big. For a V6 - 2.5" with good mufflers is more than ample. For most standard V8s a 3" system is more than plenty. Any bigger and will actually be loosing back pressure and if that drops to low you will actually loose power.

Sound:
A system with a single mid-muffler and pipe to the end will give a roaring sound, where as a Single Boom tube or canon right at the rear of the system, which will give a really throaty crackle under load (similar to Rally Cars.) but will be much louder and in an automatic vehicle can be very boomy at certian rev ranges. Your choice.

Happy searching.

Hope that helps, Cheers
 

Not_An_Abba_Fan

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I was just wondering if a 2 1/2 inch exhaust will bolt straight on to the stock cat?
Yes, as long as it is to suit your model.

Also any comments about the ones off EBay i thought they couldn't be much different to any others but i may be wrong so i thought id ask.

Thanks in advance
Jiff.
They are pretty much the same as everyone elses, because they don't sell them from a shop they have less overheads and can sell them for less. They probably work on volume rather than mark up.
 
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