sequential vs non-sequential header

upontheriversky

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Dec 31, 2007
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hi all,

on most tri y headers, i noticed pairing of cylinder 1 and 4, 2 and 3 (1-4, 2-3) which forms non-sequential header but i saw some tri y headers have pairings of 1-2, 3-4 which forms sequential header

im hunting for new tri y header but im confused with which one to choose to suit overall street performance output

anyone can enlighten me on the effect of pairings of header primaries on the power curve?
it will be good if i know the difference so i can choose which one is best for my application

thanks!
 

^pomen_GTR^

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The Mines
the arrangement depends on specific engine firing order (spark plug firing)

and the length of the Y-joints(collector) depends or taget rpm range/flow (or something like that) :adore:
 

hachiroku clan

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most cars nowdays comes with 14-23 firing order right? what cars have a 12-34 firing order? just wondering.. :hmmmm:
 

upontheriversky

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mine is kelisa and firing order is 1-2-3, anyway i just figured with 3 cylinder it doesnt matter of the pairing since firing order continously is 1-2-3-1-2-3-1-2-3

so pairing 1-2 and 3-1 gives same configuration. anyway here's the pic, note the pairing difference

powerzone:


turbo s:


my question is on the power curve for different pairing spec, i did research sequential pairing (1-2,3-4) gives high acceleration, while non sequential (1-4,2-3) gives smooth operation but i would like to hear opinions from forumer here who r&d with this topic in practical
 
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artworkz

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JB
normal L4 engine firing order is , 1-3-4-2. so 4-2-1 header is use (1-4) (2-3) confrigiration