4-2-1 manifold vs 4-1 manifold


EG6_Ash

EG6_Ash

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Joined
Dec 25, 2011
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I want to know the difference in them i know its prob been covered.
I no that the 4-1 mani gives better high end and Peak power.
And that the 4-2-1 mani gives better mid range and less peak power
But what im wanting to know is the sound different between the 2 as ive got an 4-1 manifold and it sounds like a scoobie.
And as mines a civic it sound like a one too not a scoobie :S lol
Cheers
 
that scoobie sound comes from the differing length of primaries coming together at the collector. Both types of mani configuration can give off the scoobie rumble.
 
Right i see i just thought it was that im using a japspeed mani
 
The scooby sound is a bad thing. It means the header lenghts are no equal to eachother which in turn will result in the pulse waves through the manifold not being in harmony thus not creating optimum flow and scavenging effects. Found on cheap shiny 4 branch manifolds.

Just as example when i swapped my cheapo manifold to the Toda 421 the sound went from a scooby to more of a bee/wasp constant rising tone. Showing the primary's lenghts to be in good harmony.

Its not really down to 4-1 or 4-2-1 its down to build design and quality.
 
Right i see, i was on youtube looking at some videos for some refference, im goin to have to do a sneaky and buy a better one, i thought a japspeed one would be alright hmm lol
 
Japspeed seem to be generaly turbo parts orientated. And not great ones at that.

Most the Japspeed stuff I have seen was prity shody. I wouldn't concider them a decent performance part company. More a shiny aftermarket alternative parts maker.
 
Yeah i no mate i see what u mean with, gunna have a look for a cheap good one hopefully :D
 
Tempting but im after a decent second hand one really cant afford to send for a new at this moment in time as havin a baby soon in a couple of months im limited to buy new lol
Cheers tho
 
"Decent" second hand will still be near the price of the tegiwa one.

Not worth buying one unless you get a decent make. If your on a cheap then the 98spec ITR 4-1 is the cheapest worth while option.

But just as an example my Toda cost me £550 second hand. They are the top manifold though. But expect to pay minimum £250 to £400 for a worth while second hand maifold.
 
Yeah i no was just thinking the same too, will an ITR or CTR fit on a stock b16 and will there be much difference in performance wise u know keiran?
 
The 98spec ITR 4-1 manifold is the best Standard manifold and is actualy better than any of the cheapo ones.

They usualy go for around the £200 mark. Easily the best buy when on a budget. And yes will deffinatly be better than what you have or the standard b16a one.

The EK9 one is not much different. Will still be better than the b16a or the cheapo one but not by much.
 
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Toda is one of the best header out there...you can see power gain from b16 up to b20 with high compression with this header. We have a b20 we 13.5 comp and toda works very well...
Furthermore I believe the best of all should be a custom header specific for your engine.
4-1,Stepped,with merge collector at the end and probably a megaphone.
For sure the cost for a header like this is much higher than the toda or anything else.

A good 4-1 design header,with true merge collector, should be better at any rpm level compared to 4-2-1 design and at the top outperforms everything else.

 
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??? How is that relevant to sourcing a Decent "cheap" manifold.

Plus the "best" header can be 4-2-1 or 4-1 depending on engine setup and tune. The long Tri-Y 4-2-1 headers are said to be optimum for most builds.
 
i write for the topic mate, and topic says 4-2-1 vs 4-1 design.

if you want something cheap you cannot ask for the max hp. i just talk about the performance factor.

Also the 4-2-1 tri-Y is optimum for the most set ups,(true) but 4-1 with a true merge collector, correct primaries and secondaries, stepped at the correct length and a megaphone should outperform the best tri-Y design.

 
Hello guys, and what about the Itr Jdm 4-2-1, 2.5" manifold? It's much better that b16a2 oem manifold?
Best regards.
 
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