What is the best headers for a b16a?
Is it 4-2-1 or 4-1 headers?

Thanks.

 

Typically, 4-2-1 is for midrange power while 4-1 will give better top end.
Where do you want your power at?

 

Is the 4-1 and 4-2-1 bolt on?
Also is there a difference in power on one piece or two piece headers?

Thanks.

 

A two piece 4-2-1 header will be easiest to install. Based on your question, that's what I would recommend.

And your b16 has one header.

 

How is that?

 

I have never seen a header attach to an engine any other way.
I guess there are some high end race headers that require the flange that connects to the rest of the exhaust to be welded on, but I'm pretty certain that's not what we are talking about here.

If it's the same exact header that is cut in half for flanges, making it two piece, then if there is any power difference then it is very insignificant. If it's two different headers where the geometry can be different, then you are trying to compare apples to oranges.

 

Because a b16 is a relatively tight squeeze in an EF engine bay. Unless you have an aftermarket crossmember, you may need to pry up your engine to snake a one-piece 4-1 header in there. At least I had to like ten years ago when I did it on my car. Having a two piece will allow you to bolt the upper to the engine, then the downpipe to the upper with no clearance issue.

 

4 -2 - 1 will have better ground clearance typically as well.
Get the DC sports one.
Has O2 entension and is ceramic coated. CARB legal

 

acmoc is your dc headers one piece or two piece?
Isn't there a headers thats polished type?

Thanks.

 

I have a d16, but mine are two piece
I have an aftermarket crossmember so install with a 4-1 is possible but I'd still have to lift the car way high.
The 4-2-1 ywo piece is better, better power where you use it on a street car.
easier to install as well.

Better ground clearance
remember the 4-1 collects right before the cat. So you have a big pipe there waiting to be smashed

Yes, DC makes a 4-2-1 and a 4-1 I believe
Go on their website and you'll find the correct part number

I wouldn't go polished.
You need something to keep the heat in and off the radiator.

You can get a cheap ebay knockoff and fabricate a heatshield