extractor design. (exhaust)

[SiKiD_01]

ok, can someone explain to me the concept or design of extractors/headers.

i have a set on my vit, but when i look at other 4cyl motors, the extractors are designed differently. i have not seen another one which is the same as mine.

ok, i haven't got a pick yet, waiting for batteries to recharge. but here goes.

usually, you have the 1st cyl and the 3rd cyl into one and the 2nd and 4th into another, and then into the exhaust and cat... etc. RIGHT?

i think mine is 1st and 4th cyl into one and 2nd and 3rd into another, then into the cat and exhaust.

what is the advantage/disadvantage?

thanks
steve

[SiKiD_01]

OK, my bad, its the other way around.



does it make a difference?

[SiKiD_01]

and does it look like i need a new gasket? the bloody thing is leaking oil everywhere.

thanks

[Giles]

my geni extractors look the same bud
must be a zook ting

[OldGold]

Header design is a bit of an art and people believe different designs and setups give better results. Designs will vary from brand to brand and motor to motor. Differences in firing sequence, capacities, etc bring different results to different motors, and one design may work better on one motor than another.

The three main ones (off the top of my head) are Stepped Headers, which I've never heard a good word about. They've basically just four pipes that merge into one bigger one.
Tri - Y, which is what yours appear to be, which are usually best value for money
4 to 1s, which are similar in appearance to Stepped headers, except each pipe coming out of them is of a tuned, equal length, these are generally best but are complicated to make. Every pipe needs to be the same length so the bends are much more complex than the other designs - which is expensive.

All of the above is from vague memories so shoot me down where appropriate!

[SiKiD_01]

ok cool, thanks for all that.

but, i'm still confused as to why my vit has this design, and not the other. i'm thinking firing order, and scavenging of exhausts?

i see A LOT of headers (for zooks) where the 2nd and 3rd cylinder combine, and then the 1st and 4th cylinders combine. i understand the tri y, but why are mine different? my 2nd and 4th cylinders combine and 1st and 3rd. why is this, or is it the same as others?

as far as i know, all 1.6's have the same firing order. right? so wouldn't only one design be more beneficial?

thanks
Steve

[J Top]

With the TRI Y 's you follow the firing order,1342 so 1&3 together as 1 will scavenge 3 and so on.
J Top

[ljxtreem]

i think, pipes merging at the same length = more rev's
stagerd length = more torque

just what i heard



Mock

[cj]

With the TRI Y 's you follow the firing order,1342 so 1&3 together as 1 will scavenge 3 and so on.
J Top

Actually you are looking for the opposite. You really want the greatest separation in firing sequence you can get i.e. 180 degrees. So with a Suzuki 1.6 firing 1, 3, 4, 2 you would want to pair 1 & 4 and 2 & 3. You are giving a cylinder room to exhaust the gas without doing battle with another and also improving the scavenging effect. Tri-Y's tend to give better results for street and offroad vehicles in the lower to mid-range while a 4-1 tends to be used in race applications although not limited to that as a tuned length 4-1 is designed to work best at a specified rpm. An unequal length 4-1 can spread the power over a wider rpm range at the expense of peak horsepower. There are plenty of variables in design including the diameter and length of the primary and secondary tubes along with the state of tune of the engine.

[Andrew81]

So is a Suzuki 1.6 fires 1, 3, 4, 2 then these extracors are actually set up wrong as they look to be made for 1234 firing?

[cj]

Yep, maybe the "Designer" didn't know the correct firing order, has some secret knowledge that others don't or just plain screwed up.

[Bad JuJu]

My guess on this would be price as each pair 1,3 2,4 can be both made on the one set of jigs.

[ingthorsson]

Cj is right.
I might add that as a rule of thumb, for at least 4-1 headers, for low end torque you pick headers with long, narrow tubes and for max, top end sceaming hp you choose short, wide pipes.
This is just basics, like they said: It´s an art, some magic even and in an engine everything is dependent on everything else and what kind of power you are after.

[gecko270]

What if your after both low ind torque and top end power. What is the best setup?

[just cruizin']

Just go four individual dump pipes, hot rod style
Dumped straight out behind the front wheels under the passenger door

[cj]

What if your after both low ind torque and top end power. What is the best setup?

Bigger engine

[gecko270]

Clowns

At the moment I have 1 1/4 inch from cat back which has made it zippier at higher revs yet poo at take off. Is my best bet extractors with long 1 inch pipe to increase the torque? Do you guys know where and how much to get a set for a 04' Jimny?

[droopypete]

Just go four individual dump pipes, hot rod style
Dumped straight out behind the front wheels under the passenger door

That is SO soft rooster,
go a set of zoomies staight out the bonnet
Peter.

[lay80n]

The idea of extractors is to take advantage of the vacum created in teh other pipes as one cylinders exhaust pulses flows through the system, (the scavenging effect) so for the example in the pics - Cyl 1 fires, pulse created vacum in runner No.3, which is the next to fire, Then no.4 fires, creating a vacum in No.2 runner and so on. Gas flows faster in a smaller pipr, and hot gas expands, so running smaller diamiter runners will encourage gas flow speed in hte extractors, allowing better removal of exhuast gas and creating more effective scavenging. Extractors with the 4-2-1 setup tend to work better at low revs, creating more "bottom end" , where as the 4-1 style tend to preoduce better high end power.
Layto....

[kimclive]

Extractors with the 4-2-1 setup tend to work better at low revs, creating more "bottom end" , where as the 4-1 style tend to preoduce better high end power.
Layto....

My 16 valve MPFI Vitara has the standard exhaust manifold which dumps 4 to 1. It's good off the mark and low down torque is good but at high revs (5k +) it tops out and torque/accelleration stops.

Can anyone recommend a setup that has good low down torque but revs more freely at the high end?

Cheers

Clive

[jeep97tj]

The idea of extractors is to take advantage of the vacum created in teh other pipes as one cylinders exhaust pulses flows through the system, (the scavenging effect) so for the example in the pics - Cyl 1 fires, pulse created vacum in runner No.3, which is the next to fire, Then no.4 fires, creating a vacum in No.2 runner and so on. Gas flows faster in a smaller pipr, and hot gas expands, so running smaller diamiter runners will encourage gas flow speed in hte extractors, allowing better removal of exhuast gas and creating more effective scavenging. Extractors with the 4-2-1 setup tend to work better at low revs, creating more "bottom end" , where as the 4-1 style tend to preoduce better high end power.
Layto....

Finally we have a winner, I agree with Lay80n. I have always been taught that all those type of extractors do is create a vacuum for the next cyl.

Don’t worry Steve, the people that have made your extractors haven’t stuffed them up, they have a good idea of what they are doing.

[gecko270]

Cheers Lay80n. That's the kind of info that a few of us not so mechanically minded lot on this forum are after. With that in mind I have a better idea of what my needs are.

Thanks for the constructive input.

[SiKiD_01]

The idea of extractors is to take advantage of the vacum created in teh other pipes as one cylinders exhaust pulses flows through the system, (the scavenging effect) so for the example in the pics - Cyl 1 fires, pulse created vacum in runner No.3, which is the next to fire, Then no.4 fires, creating a vacum in No.2 runner and so on. Gas flows faster in a smaller pipr, and hot gas expands, so running smaller diamiter runners will encourage gas flow speed in hte extractors, allowing better removal of exhuast gas and creating more effective scavenging. Extractors with the 4-2-1 setup tend to work better at low revs, creating more "bottom end" , where as the 4-1 style tend to preoduce better high end power.
Layto....

Finally we have a winner, I agree with Lay80n. I have always been taught that all those type of extractors do is create a vacuum for the next cyl.

Don’t worry Steve, the people that have made your extractors haven’t stuffed them up, they have a good idea of what they are doing.

my extractor design is the only one i've seen so far. on all other zooks, the extractor design has the 1st and 4th cylinders going into one, and the 2nd and 3rd into one.

does this make much difference? maybe not giving the ful vacuum or scavenging effect?

[cj]

The idea of extractors is to take advantage of the vacum created in teh other pipes as one cylinders exhaust pulses flows through the system, (the scavenging effect) so for the example in the pics - Cyl 1 fires, pulse created vacum in runner No.3, which is the next to fire, Then no.4 fires, creating a vacum in No.2 runner and so on. Gas flows faster in a smaller pipr, and hot gas expands, so running smaller diamiter runners will encourage gas flow speed in hte extractors, allowing better removal of exhuast gas and creating more effective scavenging. Extractors with the 4-2-1 setup tend to work better at low revs, creating more "bottom end" , where as the 4-1 style tend to preoduce better high end power.
Layto....

Finally we have a winner, I agree with Lay80n. I have always been taught that all those type of extractors do is create a vacuum for the next cyl.

Don’t worry Steve, the people that have made your extractors haven’t stuffed them up, they have a good idea of what they are doing.

Yes, creating a better vacuum (scavenging) is what headers are all about and keeping the pipe diameter as small as possible without creating backpressure (which you are trying to get rid of) will help keep the gas velocity up. If you have too large a pipe dia. you will lose velocity and that will cost power. Note that some people erroneously think it is because you need some backpressure but the loss of power is due to the pipe dia. being too big causing the gases to slow down and a lesser vacuum occuring. The best scavenging is done when the cylinders paired are 180 degrees opposite each other in the firing order, not next to each other. That is why pairing 1 & 4 and 2 & 3 is the ideal, not 1 & 3 and 2 & 4. Another area of power loss with a header can come from a poorly designed collecter.

[lay80n]

Extractors with the 4-2-1 setup tend to work better at low revs, creating more "bottom end" , where as the 4-1 style tend to preoduce better high end power.
Layto....

My 16 valve MPFI Vitara has the standard exhaust manifold which dumps 4 to 1. It's good off the mark and low down torque is good but at high revs (5k +) it tops out and torque/accelleration stops.

Can anyone recommend a setup that has good low down torque but revs more freely at the high end?

Cheers

Clive

Rememeber that the factory cast manifold is a mass produced item, made to a budget. Almost any aftermarkedt tuned length manifold will give a increase in flow and scavenging. For your application a 4-2-1 setup would prob be best. Speak the EXHAUSTFIX (thread in general tech) and he will should be able to set you straight.
Layto....

[cj]

Hi Clive,

I still have the Tri-Y headers of my lwb if you want. You may as well complete the collection of my bits that you have

[kimclive]

Hi CJ,

Not just at the moment, I've spent too much money this week already and only recently rebuilt the t/fer case as well.

Drop me a PM with a price though.

Cheers

Clive

[zookieboi]

yeah hi

im looking at buying extractors for my G16A anyone know of where i can buy them? do exaust shops order them in. the only place i know to look is ebay. lol and theres none there.

[nicbeer]

yeah hi

im looking at buying extractors for my G16A anyone know of where i can buy them? do exaust shops order them in. the only place i know to look is ebay. lol and theres none there.

yes about 180 and they order in

[zookieboi]

thanks
nicbeer
ill be gettin some this week ill post some before and after pics and stuff too.