Extractors - Worth the Coin?

**dubmc** · 02-09-2011, 03:04 PM

Hey Guys...when putting the car together i picked up a second hand GTI exhaust with the dual downpipes, although, i'm still running the factory exhaust manifold...however it wasn't in the best condition to start with and I think after doing a couple track days it is starting to bite the bullet...

I guess what I'm wondering is if I'm going to replace the exhaust, are extractors worth buying? Can I expect any real improvements or noticeable differences in performance or fuel consumption?

Michael.

**Preen59** · 02-09-2011, 05:48 PM

If you want to go further with a bigger cam etc, yes.

They make bugger all difference on a standard engine. But you're running decent carbies etc, so they will help a bit. Don't expect a 35hp increase or anything, though..

**sports racer** · 02-09-2011, 06:33 PM

An engine is just an air pump. You put on bigger carbies to get more air in, you work the engine to get as much air through it as fast as possible and you fit a free flowing exhaust to let the air get out faster. A 4 into 1 exhaust is the most efficient but those efficiencies are more noticable at high rpm. A 4 into 2 into 1 exhaust gives better torque down lower in the rev range. If you use your car mostly at high revs then go for the 4 into 1. For normal road use go with a 4 into 2 into 1.