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Tarderatoraka: Red-SE-00'
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Discussion Starter · #1 ·
I want to have faith in Focus Central sometimes...but I just cant bring myself to it.

4-2-1 vs. 4-1

So if the problem with the 4-2-1 is that the pipes on cylinders 3 and 4 need to be interchanged. Wouldnt this be the same affect as if it were a 4-1 header? Essentially it would all be going into one collector. Or am I looking at this all wrong??

dunnoo.....discuss.

Plz stay away from bashing FC.

Gabe
 

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"The firing order of the engine is 1,3,4,2. This means to evenly space the flow out every other cylinder needs to be joined. In other words, #1 should be joined with #4 and #2 joined with #3. This allows the secondary pipes to receive alternating pulses and doesn't exhaust two consecutive firing cylinders together."

Hmmm, that is a good question. Maybe it's that they are all firing parallel with each other in a 4-1 exhaust?, and not into each other like 4-2-1...
 

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the reason 4-1 and 4-2-1 aren't the same I think has to do with the amount of scavenging that is going on at once and how soon the opposing cylinder is scavenged.

For example : In a 4-1, it just goes by the firing order.
#1 exhaust pulse passes the collector and then #3 gets scavenged by the #1 exhaust pulse, then #4 by #3.

In a 4-2-1, #1 scavenges #3 and #4 individually. By the time the number 1# pulse gets close to the last collector to suck out the #3 pulse that is coming up right behind it in the other set of pipes it has also been scavenging the #4 pulse, then when #1 passes the collector, it sucks out #3's pulse which then also sucks out the #4 pulse and so on and so on. So it ]is different since the #4 pulse gets acted on earlier in the 4-2-1 design. Which would explain why a 4-2-1 header makes more power earlier but not as much peak as a 4-1.

I dunno, that's how I think it works.
 

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Tarderatoraka: Red-SE-00'
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Discussion Starter · #4 ·
I see I see!!

I wonder if we could just get a shop to take some pre-orders and do up a few REAL race headers for us SPIs!!

I may look into this.
 

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I see I see!!

I wonder if we could just get a shop to take some pre-orders and do up a few REAL race headers for us SPIs!!

I may look into this.
The problem is spi'ers in general like bang for the buck and don't like paying out the ass for stuff. Custom 4-2-1 headers will cost a ALOT.
 

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Tarderatoraka: Red-SE-00'
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Discussion Starter · #7 ·
yeah...this I know....

But what are the benefits of a 4-1 header??

It will all be the same on the bottle to me!!

haha
 

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4-1 will produce the most peak power but a 4-2-1 will produce more midrange power.
 

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so how much do you thing will it cost to get some bad ass header 4 a SPI????
what about focus central what happen to them are they fixing that problem they hade with the header?????
 
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