So im rebuilding my single cam vtec motor from my 92 Si.
Motor is just about done and now looking to purchase some headers.
Looking to buy some DC headers and im not too familiar with the diffrence between 4-1 and 4-2-1 applications. Also whats the the diffrence between ceramic coated and stainless steel.

Can someone explain ??

 

There are proven dyno graphs on the net that one is better at midrange, while the other is better up in the top end of your rev band, regarding the difference between 4-1 and 4-2-1.

I can't remember which is which. Do a search.

 

Header. You only have one. And you might as well get something shiny off of eBay because you don't make any real gains that warrant spending that kind of money.

As for your second question. What's the difference? Are you kidding with this one?

 

Ceramic coated steel is steel....coated in ceramic. Stainless steel is made from stainless steel.

The stainless steel is less prone to rust but needs special care while installing so it doesn't smudge or discolor improperly.

4-2-1 designs are better for low end that nobody cares about. Also better ground clearance.

4-1's typically make more power.

Don't waste $$ on a DC header unless you need CARB certification.

 

This is one of the rare times I disagree with something you say. I personally think that better low and mid would be better for daily driving the car, while the better top end of the 4-1would be better for someone who races their car. So really, lots of people should care about it...

 

We're talking about a D16. D16 and racing is an oxymoron.

 

All the more reason to gain some low and mid range, no? Because as you said, who races a D16? (Well, not N/A anyways...)

 

Negligible. With some type of CAI/SRI all you're doing is shifting the power band around. No real power.

The point I'm trying to make is that you get whatever fits your need but don't pay an arm and a leg for it and don't expect miracles.

 

Agreed. I would bet that a CAI, 2.5" catback exhaust, and header would gain at most 5hp across the band of a D-series anyways.

 

The reason to buy a performance part is usually to make the car faster in some way.

With a 4-2-1, youre still usually shifting the power upwards from stock anyway. Plus...if you're flooring it, you should only see the low end once...and you'll be in 1st.

But yes....you're right....for many reasons, a 4-2-1 is a good daily driver header. Ground clearance being a big factor.

There are 4-1's that add healthy midrange. Midrange is useful for all kinds of things. Making power from 3-5k RPM is more useful than 2-4k RPM. We're splitting hairs, though....

Neither one of the headers he's inquiring about is going to make earth shifting power. It's a gain or loss of 1-5hp in any given region and 1-3lb-ft in a given region with either.

 

Found one in the market place

http://hondamarketplace.com/showthread.php?t=3215495

 

Good for you.

 

I went and bought it so you couldn't have it. Thinking about welding up a pipe organ.

 

Thanks for all the helpful information.

 

LOL. Nice.

 

If I am correct 4-1 is mostly mid-top end and 4-2-1 is more low-mid range, I'm not 100% but that's what I believe is correct, get the 4-2-1 bro it tucks up higher so you get more ground clearance anyway, I used to have 4-1 but one smack and 1 engine mount later I made the switch, luckily the 4-1 was free lol

 

Grumble is right....It all depends on what you're trying to do on your application. I was in it for the learning and spent the money for the stainless which is great. Do some research and all the aforementioned information is what you'll come across. Now that I'm starting to get well versed, you learn that it'll be at best something that makes your engine bay look nice.

 

And car noisier.

 

4-2-1 is better for midrange due to the exhaust scavenging effect of the runner pairing
4-1 is better for top end

If this is a street car, i'd get the 4-2-1 although it isn't going to make a huge difference either way