Power and MPG Increase

[D[X]P]

I have a 96 civic ex coupe with the d16y8, with 93k miles now. The only engine mod is an AEM SRI, and I was thinking of doing the header, and exhaust for some more power and mpg. How much would the i/h/e give me? Im guessing around 10 whp or so? How much MPG increase would I see?

I live in cali, so it has to be legal. I was thinking of getting a DC Sports 421 ceramic 1 piece header. SO the 421 gives me low end power right? Whats the difference between the ceramic and stainless? SHould I go for 1 piece of 2?

Any other legal headers?

Now as for the catback, I was thinking of getting a custom one, but im not sure if that would be legal in cali. What kind of piping, size, muffler, and etc would I want. Is there any difference in power from a custom one, and an aftermarket one?

[slideways...]

id say get DC headers, since ive never had anything but good experiences with them. on a basically stock motor, 421 and 41 wont have a huge difference. id also suggest getting the ceramic headers, since you wont be using your stock heat shield, and the ceramic coating can help reduce underhood temps somewhat. as far as exhaust, california is so fucked up as it is with laws, you shouldnt have any problem as long as you can pass smog and it can avoid being too loud. oh and id work on learning how to talk your way out of the occasional ticket. id suggest mandrel bent 2.5" piping, leave your cat alone, put a resonator in, and a subtle oval muffler with a 3" or so tip. the wierd thing with cali laws is that if aftermarket exhausts are illegal, then why dont people get pulled over for those pepboys or kragen OEM replacement exhaust? yknow the crush bent mild steel stuff that old people put on their buicks when the stock stuff breaks...

[Jetts]

because they are OEM replacements

[slideways...]

but its still aftermarket, and it still has differences from the OEM exhaust. how do they classify whats legal and whats not?

[Smoghog]

Originally Posted by slideways...

but its still aftermarket, and it still has differences from the OEM exhaust. how do they classify whats legal and whats not?

Being a smogtech from CA. I thought I would chime in. As far as the exhaust it is the noise/decibal's. Too loud and it's a ticket. Too low and it's a ticket.

There are no CARB numbers for exhaust/Cat's so they are legal if they are below a certain DB level.

As for the header I would go for the 421 it is easier to install. And make sure the header comes with an CARB number. I agree with the ceramic too. It's what I have.

Exhaust, I would go with 2.25 and a 12" resonator.