Im thinking on addind the header and intake to my xB its an auto, i have been thinking is it even worth it puting performance parts on my underpowered engine, how much hp gain would you estimate from these parts together and do you think its really worth it???? i would love to give my car somemore boost w/o turbos and superchargers but would these components even do the trick???

I'm predicting...at the most, 10 hp. The TRD exhaust isn't much of performance as it is sound...

The intake should give you pretty good bang for the buck. An extra 3-5hp doesn't sound like much but trust me, you'll notice it even if you don't have a lead foot.

I'd be wary of the TRD exhaust. It's notorious for poor fit -- it tends to loosen up and melt the rear bumper around the cutout. And if you've got the automatic It has a nasty drone at freeway speeds. Too bad because other than that it's a nice exhaust.

Allan, long time no see!

I seconfd what Allan stated, watch out for the TRD muffler.

Intake header and exhaust is a good idea, Its nothing major but you can definately feel an improvement. I think they are a must for all compact cars, eliminate some resistance free up some power.

i love my aem L pipe intake , megan racing header and custom cat back exhaust , a lil loud but that's why i've got the silencer , good setup , almost , almost what i'm looking for as far as power goes, well maybe tack another 30 or 40 or 50 hp on there but yeah stock boxes blow arse in comparison lol.

would there be a major diff. in getting a cat back system compared to just the trd exhaust in hp??? would you consider keeping the exhaust and gettin custom piping, and i have noticed a lot of people do not have headers on their box is their a downside to headers on the box???

A header will not gain you very much at all. Take a look at the back side of your engine. The XB comes from the factory with a header. An aftermarket header might have longer pipes and flow slightly better, but the improvement over stock will not be that significant. The stock exhaust is a pretty good compromise between flow versus noise. Swapping headers and exhaust will get you more noise, but not much more performance. The cost plus time (labor) just isn't worth it for 1 or 2 HP.

An Intake is a much more bang for the buck. I installed the Injen short ram about 12,000 miles ago. It made a very noticeable difference in pick-up and throttle response. Only took about 30 minutes to install.

The stock engine is pretty much on it limit, there is not much room to gain horse power without force induction. if you do little math -- 108hp/1.5L = 72hp/L for a econ car is considered as very much high performance. most of others are about 60+hp/L the RAV4 for instant. Also, since we are having the auto tranny. most of the kick and push are absorbed by torque converter so you wont feel it much unless you floor it.
Over 15,000miles with the auto box, I'd say, the intake, header, and exhaust is good to have them. But don't fool yourself with these improvement will give you ability to race with any muscle car nor Japs sport car. Because way toyota designed it for use in metropolitan like tokyo, newyork. THis can be noted by its aerodynamic design and interia.
So, I am saying the box is greatest econ car with super cool look on the road. I added performance parts in it but I'd wouldn't push it over the limit.

you may also want to take into consideration that any gains you will experience are over 3000 rpms. With the auto, you're probably not going to be up in that range often / long enough to really appreciate the difference. not to poo-poo your idea at all... modding is a blast, but I would suggest a good CAI and some creature comforts like leather seats or a nice system; maybe some wheels and suspension work. Have fun!

A header will not gain you very much at all. Take a look at the back side of your engine. The XB comes from the factory with a header. An aftermarket header might have longer pipes and flow slightly better, but the improvement over stock will not be that significant. The stock exhaust is a pretty good compromise between flow versus noise. Swapping headers and exhaust will get you more noise, but not much more performance. The cost plus time (labor) just isn't worth it for 1 or 2 HP.

An Intake is a much more bang for the buck. I installed the Injen short ram about 12,000 miles ago. It made a very noticeable difference in pick-up and throttle response. Only took about 30 minutes to install.

Actually the header reall does work on our boxes, even with a stock muffler it works better than just an air intake. And the sound is really not that much louder, I heard an xB with the header, stock. The sound is not that much different and the power gain is felt right away. :eyebrow: There is a tech article on installing the header too. Also gettin an auto axle back from precisionmuffler.com combined with the header works great and the sound is deep and low. Not loud and ricey. We have already installed both on automatic scions before with no problems. 8)

You will loose a tad bit on the acceleration with the header due to it being free flowing, and you will notice the gains when the engine hits 3,500 rpm and continues to climb.

Short rams are used more so for quick acceleration such as city driving, wghere as you may want to go w/ a CAI for freeway driving. I use the short ram and drive 160 miles on the freeway everyday, and strill get 30+ mpg at 70-80 mph.

you may also want to take into consideration that any gains you will experience are over 3000 rpms. With the auto, you're probably not going to be up in that range often / long enough to really appreciate the difference.

You must drive really slow then...

what are you talking about?! i have the manual. the car is at 4K constant going 80 on the highway. simply stating that the automatic would not be in the higher rpms that much, simply due to the nature of the auto. *maybe* if the OD was turned off, the auto would be in that range for 2 gears max. sheesh!

the automatic scions have three speed Overdrive units and are not that much lower in RPMs than the manual.