Well it also has alot more torque, you dont have to floor it to keep up with traffic, basically partially closed throttle will lessen the air intake of the engine, thus fuel will also be reduced. Really comparing a V8 to a I4 is like comparing chokolate to shit, you can guess which the I4 is.
On another note, headers, exhausts and intakes are put there by engineers of toyota/whatever car manufacteurer you want to pick, they do calculations and computer simulations on efficiency (on econo cars) and on performance (sports cars). Now you think some ricer-brand-ebay parts really develop their parts that well, do they do computer simulations and tests, no they dont. Most of them are just there to make it look bad ass. Now really, can you really keep a straight face and say that Ebay-parts/ricer-parts actually increase mileage AND power? I sure as hell cant and I find the claim absolutely ridiculous.
Toyota spends millions in their R&D to achieve their goals, ricerparts are generally made by someone with a tig that thinks something looks cool. But hey since its cool its gotta work right?
And more, gaining power with plugs. Sure it sounds good on the internet, but go ask ANY true engine builder, not tommy-the-wrencher at the local import-shop about getting power with sparkplugs and see what they have to tell you. 9hp with plugs, big f'n haha.
Only way to have mileage is to keep your car absolutely stock, I mean 100% stock, moment you install that big ass stereo system, you'll bring load to the charging system and you'll lose some efficiency. Keep the AC off, windows closed, dont listen to the radio. Of course maintain the car aswell, you'll get mileage for sure, but is it worth all the negative aspects to cry over few miles? not in my opinion.
Linear Mode
