4-2-1? 4-1? Extractors broken down!

[biz-da-tech]

ahh cant wait for the piping info... really interesting on that 1 i felt.

 

[kumbang]

ahh cant wait for the piping info... really interesting on that 1 i felt.

me too, most post by izso :top:, all really informative.

i'm a nub on car mods.

 

[LOPI]

Thanks bro for gud info..you really helping us to understand much better..go through detail..:)
For those who confius this tread really help..

 

[Izso]

As I've mentioned a few times before, the real sifus are the ones in the background keeping quiet. I'm only sharing what I learnt from them. In this particular case it's Drexchan's extractor post, not mine! so kudos to the silent sifus

 

[csl]

How can the valve over lapping coverage missing in an exhaust related topic?

 

[Izso]

How can the valve over lapping coverage missing in an exhaust related topic?

Erm.. this is an extractor topic, not exhaust topic. Not quite the same thing? Related but not related. LOL

 

[drexchan]

We are assuming the entire head assembly being untouched, with only the extractor replaced, and comparing both common types of extractor for a straight four. This is the most common thing beginners do.

Advanced users will look into optimizing the performance (with the new extractor) by means of cam adjustment, air/fuel ratio and ignition timing. Some will go further with port & polish, valve angle cut, high compression, management, etc.

However, whatever one do to a 4-2-1 can't make it performing like a 4-1, or vice-versa. Therefore the other tuning techniques are not discussed here.

 

[D7zul]

After calculating..

the right extractor for me is a bigger 4-2-1

namely HKS extractor.. any1 here have this for sale???

 

[r3dster]

hmm..good read.
but i've been reading around and yet still unable to get a concrete answer to it.
if 4 - 1 provides power at higher rpm and 4-2-1 at lower...
how about...equal lengths and unequal length headers? as such for example; scoobies have performance setup for both equal and unequal lengthed extractors....
dispite the fact uneqal length gives you a much clear growling,but....if aftermarket high performance company makes both of them surely there's a difference in it's output...anyone has a concrete answer to this?

Thanks a bunch

 

[Izso]

hmm..good read.
but i've been reading around and yet still unable to get a concrete answer to it.
if 4 - 1 provides power at higher rpm and 4-2-1 at lower...
how about...equal lengths and unequal length headers? as such for example; scoobies have performance setup for both equal and unequal lengthed extractors....
dispite the fact uneqal length gives you a much clear growling,but....if aftermarket high performance company makes both of them surely there's a difference in it's output...anyone has a concrete answer to this?

Thanks a bunch

You're getting into specifics and that's more advanced than what Drex has explained. Have a read here and see if it answers your questions :

Custom Extractor

Apparently this guy got inspiration from someone in ZTH! Doesn't really talk about how he did the calculation though but is still a pretty good read.

 

[1JZtezza]

You're getting into specifics and that's more advanced than what Drex has explained. Have a read here and see if it answers your questions :

Custom Extractor

Apparently this guy got inspiration from someone in ZTH! Doesn't really talk about how he did the calculation though but is still a pretty good read.

IZSO:

the link is here:Exhaust Length,exhaust pipe,induction

Have fun...not sure of its accuracy!!... and unless you want to squeeze every last drop of bhp from the engine( full race specs) who wanna try????...please document

 

[r3dster]

eyh...nope..they just mention tuned length...
altho it measures by split seconds...it's just good to know stuff..
haih...back to the www..

thanks tho :)

 

[drexchan]

Yeah it wasn't my intention to go that deep. I wrote this to answer the FAQ from my customers on what type of extractor they should pick. It's largely general and basic.

It's good to know that my pebble actually crated some new waves. Good sharing everyone, keep it up!

 

[deenweirdoz]

Ok this post is very informative, now I know

 

[zuruzuruz]

zth is an institute for all motorheads..