Hi all

Just curious.Do you think I must replace my genuine GX 4-2-1 extractors with a 4-1 extractor? What are the benefits of a 4-1 extractor.
Does it really make a improvement.

From what I have picked up from around the traps 4-2-1 is better for street use ie low down torque. 4-1 is better for top end performance (high RPM use).

Not sure if you will actually feel any differance at the throttle but you might see a few tenths down the quarter or a few extra neddies on the dyno.

I have 4-1 on my 1200 and find it a bit of a pig down low but that also has something to do with the large cam and no back pressure 2.5in exhaust

im using 4-2-1 previously was 4-1 so far
4-1 for high end rpm 4-2-1 for low rpm ...
4-1 for a higher fc ( fuel comsumption)
4-2-1 FOR LOW FC...

as a "general rule"

4-2-1.. is more torquey..

and 4-1, are for higer rpm power..

not so sure about fuel consumption.. this would mostly have to do with the right foot and the state of tune, and HP being made..

now this can open a can of worms, who designed the pipes, what bends what lengths.. theres a black art to making pipes...
every set should be made to suit the vehicle, state of tune, dif ratios, driving style etc,

burns stainless is well worth a look.. (be warned.. multiple amounts of 'erotica' on that site.. U will need deep pockets..

7 vs. 5 is not the question.

The stock GX manifold is short tubes. Aftermarket headers/extractors are long tube. It will be a big difference. That's the question.

id say its 1 vs 3