how much horsepower does a cold air intake add on a v6 eclipse?

From just the cold air intake, probably closer to 10 horsepower on that engine. The engine will be noticeably healthier with intake and exhaust mods.

I used to have a 1995 Lincoln Town Car and I put a cold air intake on it. It made 210hp stock (same as your Eclipse) and I noticed a worthwhile improvement in engine performance and sound after the install. People who say "It'll only add 2 horsepower" are usually performance snobs that think power adders like nitrous and superchargers are the only significant improvements. Cold air intakes do make a difference otherwise there wouldn't be such a huge market for them. And they look cool to boot.

The intake itself will only give you 3 hp an maybe .50 estimated hp at the wheel. Only thing there good for alone is sound,now with a full exhaust the intake hp wont change but the effect that its suppose to have will supply more air to the engine. In actuality without the full exhaust you're most likely losing 1-2 hp. More air being sucked in but isn't escaping through the stock exhaust as quickly.

OK I have news for everyone here. Listen close. Adding an air intake on your car does NOT add horse power to your car........ Did everyone get that? The only thing it does do is provide cooler air to your engine to PERFORM better. Thats why you noticed the car seem to go faster at high end because its getting better oxygen. It is better to race when temp outside is between 40 and 70 degrees than to race under or over that becasue warm muggy air is worse on an engine performance wise along with air below 40 degrees.

Not much. At MAX 8-15 HP, no more, no less. All it does is allow cooler air into your engine for better explosions (combustion engine). You'll blow through your gas quicker at high rpms though.