Hi fellas, can anyone detail what happens when the WRONG extractors are fitted to a 100kw Redtop. By wrong, I mean that a 4 into 2 into 1 system where pipes 1 and 3, and 2 and 4 are joined instead of the conventional 1 and 4, 2 and 3. What effect would it have on power, will the engine run hotter, will the pipes run hotter? And, why is it that it needs to be 1/4, 2/3 regardless of what 4 cylinder engine it is, and regardless of whether it fires 1342 or 1432?

uneven sounding exhaust.......... like a subaru and unequal back pressure..... theirs a reason 4-2-1 and 4-1 headers exist

http://auto.howstuffworks.com/question172.htm

Thanks for the link. But I'm still mystified as to why the firing order, and hence, pulses, doesn't change the joining order of the pipes, it's always 1 and 4, 2 and 3, on a 4/2/1 system on a 4 cylinder engine unless it's full race with a straight 4 into 1 system. Any one else got ideas?

You need to research how exhaust gas pulses work, and how they are taken into consideration when designing a header.

Interesting..i've looked at one of those $1500+ headers from JSP, hasselgren, ect. & i see a well tuned, equal length, placement order of pipes..maximizing scavaging....?

Sure wished my headers looked & performed like these bad boys