Aftermarket Exhaust; More Power?

[jdium]

Originally Posted by Astroman

Well, I did manage a 17.356 quarter mile time, about a half sec quicker than stock.

Half second quicker than YOUR stock time, or some magazines stock time? Just askin, cuz 2 hp is worth about nothing in the 1/4 mile. Even if you want to consider it a 2% increase, that means you would cut .35 of a second off you're time, all things being equal...but if you happen to have a slightly lower temp, or a slightly higher tail wind, or a slight change in relative humidity, or a slight change in tire pressure, or a little more or less caffeine in your quick twitch system, or a stickier track, or a slightly higher rpm launch, or just Zeus helping you, going a half second faster than 17.856 is like a 350 lb chick losing 12 lbs, she's still fat...

[hasher22]

An aftermarket lightweight pulley doesnt give u more HP, it just revs up faster thus giving u faster speeds....

an exhaust will give u hp gains thus more airflow, so will a muffler.......

[RUBBERDIPSTICK]

can anybody post some dyno results of before and after an exhaust mod? I'd like to see what the gains are, and what if any losses there are at low rpms...thanks.

[seanele]

Originally Posted by Spades

LOL...found a soapbox? LOL...i never leave one. I am always on it,lol.

yeah, performance gains are little at best, and you have to be very careful on your muffler selection or you will end of sounding like a un muffled chain saw.

so yeah, worth it to some, not to others.

<picks up soapbox and carries it with him to the next post>

or end up being pulled over due to noise or complains by neighbor..

[WRBlue]

Originally Posted by hasher22

An aftermarket lightweight pulley doesnt give u more HP, it just revs up faster thus giving u faster speeds....

Lightweight and underdrive don't create more HP but they do free up HP lost due to parasidic drag. Your engine makes the same power, but more of it is transmitted to the wheels. Its the same thing as a lighter flywheel, lighter wheels, or a more efficient transmission - none make more power, but they will show up on a roller dyno. Everything but the wheels will show up on a hub dyno.

Faster revving will not get you to speed faster, only more wheel HP. And it definalty will not let you go faster - thats either a function of HP and drag OR transmission gearing. Faster revving will give you better throttle response and worse shifting till your used to it - revs will drop faster too, less mass=less kinetic energy.

[myt]

MYT, does that make things less confusing for you?

But I agree with the idea that gains with the Yaris might be minimal. On previous car I experienced a very noticeable boost across entire power band, even w/o replacing header. But it had about 30 lbs of stock air box and baffles and shit blocking the flow, Yaris does not seem to have that problem.

Yep...LOL FWIW I just wanted to get one that made a little manly noise. LOL I heard that this one wasn't too loud and annoying so I looked into it, but in the ad it said more power and that is what I couldn't understand.

MYT