hey guys me and a mate are trying to design our own set of extractors to fit right into a twin exhaust system what we wnat to dois have 3 cylinders fireing into 1 half and 3 into the other half... my question is do the cylinders/ headers fire in any specific order if so what are they.... and would doing what i want to do would i gain more power?

s**t man, theres alot of testing to be done designing your own custom extractors before it gets better than tried & tested pre-made ones.

For starters youd wanna find out what revs the car makes peak power then make the pipes all the same length at a certain point (tuned length). This will make peak power where the motor likes it but in turn suffer at low revs. My 2c.

if it's a falcon 6, the order is 1-5-3-6-2-4

my car suffers low end quite abit its bout as even as a vn but 3000rpm i launch ahead of them by miles so id say it owuld be the 3000 - 3500rpm mark..

Keep the 6 into 1 as this is a favourable set up.
Ralph sarich found out while using a suzuki 3 cyl 2 stroke that the exhaust pulses were most helpful at 120 degrees apart which is 3 cyl 2 stroke or 6 cyl 4 stroke.

Most people laughed at Bromlech when they brought out a 3 into 1 expansion chamber for the Suzuki 2 strokes but it made good power all through the rev range.

It is always horses for courses. Do you want peak torque at top revs then zoomies (Individual runners).

Want torque lower down then collector type.

Designing extractors is a science in itself and the good companies provide them in differing sized tubing and lengths for different capacities, rev bands and whether they peak or are flat across that range.

Do the duals but you would have to do a lot of research to top premade from a reputable company.

Hope this helps

Grumbles

Wouldn't it be easier to get a set of extractors that go into 2 before they go into one and chop them where they are still 2?

DESIGNING BETTER EXTRACTORS

This project must be progressing - got an update? - Reserching the gas flows, sonic and thermal dynamics should be a snap now sombody told you the firing order. I appreciate the difficulty involved so I see where you are coming from. What about making a 'big bang' motor? Worked wonders for the low end traction issues in 4cyl GP1 bikes. Then you could specify your own cylinder groups and firing order.

YHGTBJ

C