I have put a cold air intake, cat back exhaust, and next week i am puting a header on. Now what i want to know is how much horespower gain i can expect?

According to magazines about 4 HP.

I would say a good 5-15hp at least.

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98 ESi
95 GS

Not a lot. The intake you will be your most noticible difference in both sound and hp, but still, the gain isn't that much. I'd go for ColdAirIntake and an UDP, instead od headers. I've heard headers do basically nothing.

______________________________

Ryan
IRyanHester@Hotmail.com

'03 Mazda 6s

yea.. import tuner basically killed anyones dreams of getting a NT eclipse with that tuner article they did...

like evilpee said... get a AF/X Underdrive Pulley (www.ptuning.com... use the link on the mainpage to get 5% off) instead of headers. Import tuner said greddy headers only gave about a 0.4 horsepower difference... so even if they are wrong.. it's still not worth the cash. UDP will free up about about 5-10 horsepower.

Only reason to get headers would be for show.

I put on my injen intake (non-cai) and i felt a good difference in the pull.. especially around 5000-7000 rpms.

16.1 @ 87.11
http://www.virtuallyinfamous.com

ARD 57mm tb and p&p manifold, Neuspeed STB, Pro-kits, Illuminas, Injen CAI with K&N, 2.5" pacesetter catback,
AF/X UDP, Rear STB, Powerslot rotors, RRE SS Brakelines.