Scion XB Forum banner
1 - 20 of 33 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter · #1 ·
I have a stock 2008 xb and am looking to squeeze out as much Horse Power as I can for the least amount of money.

I was originally looking at turbo kits, but that's just not in my budget.  I'm hoping everyone can help me decide what is the best mods to make while not breaking my bank entirely.  The number one issue I want to avoid is making sure I keep this entirely street legal and can pass smog tests.

The first upgrade I was thinking of was either cold air intake, an intake manifold mabye...

I was looking at the Weapon R race intake manifold and thinking it sounded the best as far as my first step because for the money, you can't beat this HP upgrade. 
Has anyone installed one of these yet that can advise if this is a good idea?  Or just help me get started?...
http://www.fastscions.com/scion-tc-xb2-weapon-r-2azfe-sheet-metal-race-intake-manifold.aspx


Can anyone suggest any good starting points? Just looking for some good suggestions on what others have done to their XB's
 

·
Registered
Joined
·
317 Posts
First off, welcome to the site.

The intake manifold won't do you any good unless you have a turbo. I'd start off simple with a cold air intake, then an exhaust.
 

·
Registered
Joined
·
739 Posts
Start with a TRD CAI an then the NST Pulley.
 

·
Registered
Joined
·
342 Posts
Cold air intake is probably the easiest but it gives you minimal hp from what I hear with our xb's defintly less than 10. ?fter that I'd say exhaust is up next after for easiest hp. But if your looking for the most horsepower for the money it has to be a turbo. So instead of spending atleast $500 on an exhaust and cold air intake you can use that money and save up towards a turbo.
 

·
Registered
Joined
·
28 Posts
The cheapest way to make it faster would be to lighten it. Remove the spare, rear seat, sound deadening, trim, etc.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #6 ·
Bummer, so Cold air intake is not all that great? I got this car with the factory TRD exhaust. Do you think it's worth it to go get new exhaust over the factory TRD? Will it be a noticable improvement?

gr8scape says to start with a TRD CAI an then the NST Pulley. Does anyone know how much HP we'd be talking about with these upgrades?

Also, I'm not sure if by doing any modifications, will this void my warranty on this car? I'm still not 100% possitive if I want to try to beef up this car a little bit, or if it's just not practical.

Is there no way to squeeze another 30-40hp out of this little 4-banger?
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #7 ·
I was also just talking to my freind who was doing a little research on the CAI's. he said he read the TRD added factory CAI was not as good as other brands.

Who is using what CAI's? I'm wondering if there is one brand that is specifically the best.

Does anyone know of a way to compare the different brands to figure out which one will give me the best improvements?
 

·
Registered
Joined
·
167 Posts
grza said:
Is there no way to squeeze another 30-40hp out of this little 4-banger?
Dude, you should have bought another car if you are looking for HP numbers like that. You are going to spend a lot of money to get that kind of HP increase out of this car.
 

·
Registered
Joined
·
783 Posts
drop in a new engine.
 

·
Registered
Joined
·
342 Posts
Chrevis said:
drop in a new engine.
I dont think that is a very easy way to gain horsepower. Takes a lot of downtime and money for an engine swap. This is a guess but im pretty sure it would void your warranty as well.

Going with a turbo will not void warranty unless you blow your engine because your psi is set too high or installing the turbo kit incorrectly. They must prove that your aftermarket part was the cause of the damage to void the warranty.
 

·
Registered
Joined
·
739 Posts
There is no inexpensive way to get more horsepower. The NST Pulley will give you a weight reduction (probably around three pounds) which gives you more power because the rotating mass is less. The TRD CAI gives you some horsepower gain because it is getting cooler air from outside the car rather than from inside the hot engine compartment.
 

·
Royal Floor Sweeper
Joined
·
4,314 Posts
Unlike older cars where one could gain notable HP fairly easy by allowing the engine to breathe better, newer ones are pretty efficient. That is mainly due to economy and modern engine management being so much better than in the past, as the manufacturers now car so much about economy (a couple MPG is HUGE to them) and want to avoid the "sluggish" and "underpowered" tag so they also look for power too.

So, it gets down to small and incremental "high cost/HP" added vs. expensive initially but much cheaper "cost/HP." The best cost/HP right now is the turbos out there, such as the one from World Descent (also sold through Sparks) that was developed w/ Chris Rado. Other stuff helps, but only little-bit at a time and only to a fairly low overall improvement in power.

As for the various CAI and Ram Air intakes, each works a bit different and is designed different. So, it isn't as easy as comparing one number. Most just "move HP around" by sacrificing low and mid-range for better top end. Cold air works by drawing in colder (denser) air quickly into the engine. Ram air works by forcing air (by "ram effect" into the engine intake manifold.

The TRD one is a Cold Air primarily, but also works as a ram air when at speed by the intake vent pressurizing the fender well to create a ram-air effect as well. In comparison to others, it isn't the highest top end, but improves the power curve across the powerband. Many don't do that at all. As most tests are conducted stationary on a dynometer, the "ram-air" effect isn't taken into account and thus don't reflect what they actual do on a vehicle in the real world. I did a fair amount of research on them and read the tests (speculatively), then decided to get a TRD one from Sparks (GREAT servive!). I've been happy w/ it.
That said, don't expect a huge difference by just ANY intake. An intake w/ a well designed exhaust is better than each independently.

While on exhausts . . .
Also, be weary of simple numbers too. Normally aspirated engines rely on a certain level of back-pressure for low and mid-range torque. That backpressure is lost on many high-flow designs, so again mid-range is sacrificed for high-end numbers.
There are a number of exhausts out there and I haven't been able to decipher between what I want (improved cross-band), just top-end, and those who care only about sound. Thus, I am still on stock exhaust (for now).

Another factor for "performance" is the unsprung-weight in the wheel area, esp. the wheel itself. It is a matter of momentum physics (objects tend to like to stay either in motion or not, as they are). Heavier wheels take more effort to both stop (brakes) and start (HP) moving, w/ very heavy wheels also affecting the effort needed by the steering system to change direction and working the suspension much more. So, the heavier a wheel (rim/tire combo) is, the more it "robs" performance. Conversely, lighter wheels effectively increases power, braking, and handling.
The old adage "Lighter is better" and "adding lightness" as ways to improve performance is true. As much difference as body weight reduction makes, unsprung wheel weight makes MUCH more difference.
My own vehicle is awaiting Rota Slipstream rims in 16x7, bought largely b/c they weight 14 pounds each, a drop in 6-8 pounds/rim (depending on if the steelies are 20 or 22 pounds, the two weights I've kept seeing and haven't weighed mine yet as they are on the fridge).
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #13 ·
Well let me start by saying thank you all, especially TartanJack! This has all been very helpful and I appreciate everyone's input.

I might have been a bit hasty to say I was hoping to pull another 30-40 hp out of my car. The one and only other car I've ever actually worked on improving power was a 1971 pontiac ventura, so 30-40 hp was in headers.... haha.

I'm still getting used to my only 4 cylinder car, and I really dig this car. Even stock it's speedy and handles great, I just want to be able to beat all other XB's I pull up next to.... =)
 

·
Registered
Joined
·
781 Posts
grza said:
Bummer, so Cold air intake is not all that great? I got this car with the factory TRD exhaust. Do you think it's worth it to go get new exhaust over the factory TRD? Will it be a noticable improvement?

gr8scape says to start with a TRD CAI an then the NST Pulley. Does anyone know how much HP we'd be talking about with these upgrades?

Also, I'm not sure if by doing any modifications, will this void my warranty on this car? I'm still not 100% possitive if I want to try to beef up this car a little bit, or if it's just not practical.

Is there no way to squeeze another 30-40hp out of this little 4-banger?
30+ HP? Forget it!

If you're lucky, you may be able to squeeze out 20HP. The TRD CAI is fine, if you like it, get it, it will help. The exhaust you have now is fine, changing to something else will make very little if any difference. Switching to a light weight pulley will assist acceleration. Installing a good header will also help, though recognize that doing so loses your precat. May or may not be an emissions issue come inspection. You can get a Super Chip setup for whatever HP mods you get and that will also help.

However, as already said, if your intent is a major HP boost either go turbo or get a different car. N/A inherently has limitations, but given the other mods, the intake manifold upgrade can also make a difference.
 

·
Royal Floor Sweeper
Joined
·
4,314 Posts
I know the feeling of a lot of work for little benefit :lol:

My 90 Miata has migrated pretty far from stock. It has an early production DDM intake, Racing Beat 4-1 header (original cracked and that was cheaper than a new stock one), high-flow cat (only has 1), Racing Beat "Pulse" exhaust (bafflers in original rear muffler broke loose and it sounded awful), plus all the "tweeks" like bumping up the timing from 10 degrees to 14. In the tranny, I have a 1.8 performance clutch and lightened flywheel (came w/ replacement transmission from car once owned by the local Miata dealer- who happens to be a race car driver too-> was low miles since major rebuild/improvement and someone hit him to total the car).
With all that, I'd be happy w/ 15 HP improvement, as the Miata is pretty good to begin with, and would be stunned if it is anything like 20 or more. Stock HP is 115 listed at the crank and about 90 at the rear wheels (just over a 20% HP loss through the transmission).
A blower, like a supercharger (there is a GREAT one for Miatae that add 70HP and will last forever) or turbo (like offered by Flying Miata) would have been MUCH more cost effective for the HP.

As the xB is even more efficient in stock form, a CAI is a slight improvement and all else is very minor w/o some sort of blower.
For handling, I'd certainly get a TRD rear sway or matched set. That makes a HUGE difference.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #16 ·
Ok, first of all I want to thank everyone yet again for all your thoughtful input.

This is what I'm thinking of going with now:

So far stock from the factory I got exhaust and rear sway bar w/lowering kit. so the car handles great already and the exhaust would be silly to buy another set up.

I'm thinking Fujita CAI for sure. Found it online at Yoparts.com for $204.95 ($30 cheaper then Fastscions.com)
http://performance.yoparts.com/i-129954.aspx

I was originally thinking of getting the lightweight crank pulley from House of Billet, but since reading up on losing the harmonic balancer, I'm concerned about the long term effect on my engine and it's warranty. For now I've decided against this.

I'm still thinking of getting the House of Billet throttle body spacer even though I read it can make the fit of the CAI a little difficult.
http://www.fastscions.com/scion-2azfe-throttle-body-spacer.aspx?variation=936

And lastly I'm definitely wanting the Unichip engine management system: http://www.fastscions.com/unichip-p...ine-management-system-scion-xb-2008-2010.aspx


I still haven't heard of anyone using the throttle body spacer though.... anyone who has installed it have any input?
 

·
Registered
Joined
·
739 Posts
Throttle body spacers do not work.
 

·
Registered
Joined
·
781 Posts
A quality lightweight pulley is ok for normal road use, but it has to be quality, and it has to be non-performance driving. Anything else is a mistake IMO. I tried to identify as many as a single person who had good experience of a spacer in our cars -- I failed.
 

·
Registered
Joined
·
21 Posts
easy and cheap hp upgrade?

well for more torque to the wheels and better shifting, look into the Weapon-R torque damper kit!

really helps, especially if your xB is a manual!

here is the link:
http://www.fastscions.com/scion-xb2-weapon-r-engine-torque-damper.aspx

its not adding hp or torque but, it more like unleashing some hp and torque. mainly torque ;)
 

·
Registered
Joined
·
342 Posts
^^^^
hotbox toke machine is 100% right on that one.

lol funny name is that what you use your xb for?
 
1 - 20 of 33 Posts
Top