[rton20s]

Besides my own threads, there have been a lot of people talking about "building" more power with natural aspiration. Below are my own thoughts (and my personal recommendations in italics) for a N/A build up.

1. Intake - You have to get the air in before you can get it out. I've seen no proof of significant performance gains anywhere in the powerband with a cold air intake vs. a short ram. So, go with a short ram and save yourself some money.
Recommend: Fujita SR-3100 due to MAF location.

2. Exhaust - Other than sound, you won't see much gain from the typical axle-back exhausts sold for the xB. The most gains are going to come from a custom-made, header back, mandel bent exhaust. You'll need a high quality exhaust shop to build something like this for you. From pipe sizing, to muffler selection, they will have to design it to meet the specific needs of your build. If you plan to go with a typical retail exhaust, you should go cat-back if you want any real gains.

Recommend: Magnaflow cat-back due to mandrel bent, stainless steel design and proven gains.

3. Header - Gains can definitely be found here. Avoid cheap ebay headers, as they don't perform as well as some of the nicer headers, and usually have a much lower build quality.

Recommend: Greddy if you have the budget, Weapon-R if you do not. I actually own both of these headers. My Greddy is not installed yet. The Weapon-R performs well, but the build quality does not compare to the Greddy. This is most noticeable inside of the header, where it counts the most.

4. Spark Plugs - There really isn't much to gain performance wise here. Other than to make sure your plugs are clean and gapped correctly. The only use for platinum or iridium is a longer life cycle. Don't let anyone sell you on a performance gain. Standard copper plugs will work just fine if you plan on changing them out at regular 30k mile increments.

Recommend: NGK V-Power BKR5EYA with 0.32 gap.

5. Clutch - Anything Stage 2 or better from a reputable brand should suffice. Depending on how extreme you attempt to go, you may want to go to a stage 3 or better.

Recommend: Can't really give a recommendation here, as I haven't change out my clutch yet. Though I have kept and eye on Spec clutches as they seem to be a bit less expensive than most of the competition.

6. Flywheel - A light weight flywheel can help to reduce parasitic loss and the reduced weight can help extend the life of associated parts.

Recommend: Fidanza, as it seems to be one of the only options out there.


7. Axles - If you ever start making decent power, you might just need some new axles. Unfortunately there aren't a lot of options out there. They are very expensive, and only worth the investment if you are making power comparable to boosted applications.

Recommend - The Driveshaft Shop since they are the only option out there. Very high quality though, and rated at 600 hp.

Then we get into the more cutting edge side of things going on right now.

Throttle Body - Many owners are currently looking into the 1ZZ-FE throttle body for the 1NZ. The Yaris community is leading the way on this. Some owners have had no problems other than a bit of a high idle. Others have problems with oscillation, very high idle and CEL. Some have been attempting to address the issue by swapping the "chip" or board from the 1NZ throttle body onto the 1ZZ throttle body. The jury is still out on this one. Gude is also apparently now porting stock throttle bodies to coincide with the other work they can do for the xB.

Intake Manifold - Weapon-R has had one in development for quite some time. And it seems to finally be making its way out into the public. I don't like to speculate or spread rumors, but there was a lot of talk early on that they actually lost power on the low end with this manifold. I have yet to see a dynograph for this manifold on a naturally aspirated car. Weapon R is promoting it for turbo use and claims a 50hp increase. (Which I find extremely hard to believe, unless they are including the gains from the turbo as well.) $600 MSRP is a big risk on something that doesn't have a single dyno to back it up.

Another company called Dynatek has also been working on an intake manifold for the 1NZ. They began with the Yaris and are considering developing for the xB if they can get enough commited buyers. Dynatek has provided Dyno graphs showing moderate gains throughout the powerband, with the biggest gains at the high end. They made a peak of over 114hp to the wheels with an intake, their own long tube header and free flowing exhaust, sans cat and no CEL. Estimated pricing for this manifold is $700 if they can get 10 interested buyers. More expensive than the Weapon R option, but at least they have some sort of dyno number to back up their product.

Heads - Others have tried in the past to do headwork, with very poor results. Gude performance claims to have found the right combination after several attempts of trial and error. They do not list any sort of pricing for the head work, and as far as I know, they have only done work on a single sponsored car. Running the heads with a custom cam grind, intake header and exhaust they made over 116 hp. The cars owne suspects that with engine management you may see between 5hp and 10hp more. Though this us just speculat ion.

Cams - As mentioned above, Gude is able to do custom grinds. They did the set for the car they did the headwork on. Lift was 420 with a duration of 244, and were ground with the owners supercharger in mind. I am sure they can do other grinds. Crower also has the ability to do cam regrinds, though you will have to give them your own specs.

Engine Management - There really are too many options out there to list. There are two basic types, piggyback and stand alone. To get t he full benefit of your build with maximum control you will have to go stand alone. Though doing this will usually mean having to find a much more competent and experienced tuner. Piggyback units work just as they sound. They interpolate data from the sensors and ecu in order to adjust the engine management to your specification. Right now it is looking like the AEM F/IC seems to be panning out the best. Though it does not provide the ability to advance timing yet, only retard it.

Pistons - Forged pistons have been out there for a while. Several companies have been making them. Though most companies are only offering lower compression forged pistons for boosted applications. Your best bet is to contact vendors and/or manufacturers directly to ask about higher compression forged pistons.

A possible alternative to the aftermarket forged pistons is to run 1NZ-FXE (Prius) pistons. These will bump compression to 13:1 if they work. Unfortunately no one has tried this yet to see if there are any interference or stress issues. Completely swapping a Prius bottom end could work as well.

Rods - These have been around for a while as well. Carillo seems to be the most popular choice.

That is all I can think of right now, as it is a quarter 'til 2:00 in the morning and I have been up since 6:30 yesterday. I'd love to see contributions and comments from others.

[ogerdgonz]

The weapon R intake was dyno tested on a 2006 xA.


All of the NA mods out there when combined for money and gains are not worth it compared to a supercharger or turbo.

$600 for abput a 5% increase does not seem worth it.

The Thermal Research cat back exhaust I have to put on gives close to the same results.
"On the dyno, peak power output from the Thermal unit came in at 98.31 WHP and 102.52 lb/ft TQ,

For this test this is the car used and the base numbers.
2006 Scion xB RS3 - STOCK Exhaust
Tested on DynoJet Chassis Dynamometer
As tested: K&N Cold Air Filter Installed
Baseline w/Filter: 96.96 WHP, 100.53 TQ

Here are the numbers for the other exhausts tested on this car
Blitz 96.37 WHP 100.10 TQ
JIC 97.71 WHP 102.23 TQ
Espeiler 97.33 WHP 100.91 TQ
Strup 97.57 WHP 100.42 TQ
Power Enterprise 97.41 WHP 100.90 TQ
Cat back systems
Borla 98.10 WHP 102.04 TQ
Magnaflow 98.31 WHP 102.27 TQ
Thermal 98.31 WHP 102.52 TQ

[Timmay]

Very good write ups. I def need to subscribe here for when I start modding the xB

[rton20s]

Thanks for the reply ogerdgonz, this is exactly what I want to see in this thread. My posting is in no way definitive, and I want as many people posting their own experience, knowledge and dyno information as possible.

It's good to see the actual dyno for the Weapon-R manifold. It actually did better than I suspected, but as you said, is still quite expensive. Then again, so is the offering that may be coming from Dynatek. It would be nice if we could see a shootout between the two on the same vehicle.

Also, thanks for reminding me of the Tuner Performance Reports exhaust shootout. I wish they were able to do similar shoot outs for other components, but I know at this point it will never happen for our xB.

The Thermal R&D cat-back is another great exhaust system, very comparable to the Magnaflow. Pricing and performance are nearly identical, so it really comes down to style and sound preference when deciding which to choose. Borla is another decent option, but requires you to cut an additional exhaust opening on the driver's side.

And there are definitely cheaper ways to make power than trying to go with a totally naturally aspirated build. Nitrous is probably the cheapest initial investment, but can cost you quite a lot in the long run. It also isn't an "always on" option like with N/A builds or forced induction.

[PCH]

Very interesting writing, rep points for putting that info together
Would like to hear your opinion about:
1. VVT-i controller
2. Different header configurations
3. Throttle body spacer
4. Lightweight crank pulley
Since we are talking about N/A, why do we need aftermarket rods? I understand they are stronger, but what about their weight? I understang the forged vs. cast thing, i just want to know if they are heavier or not.
As far as WeaponR manifold: i wish they took time to do more dyno testing with legit base runs to show that it really works.

[rton20s]

I'll try and just address your comments in order PCH. By the way, thanks for contributing to the thread.
VVT-I Controller - I will try and address all of those out there that people may THINK are VVT-i controllers. Keep in mind, I am not a tuner or even a mechanic. When it comes time for some sort of engine management on my car, I have a local tuner I will go to in order to work out all of the kinks.
First is the AEM F/IC. This is a piggy back unit designed to work in conjunction with the factory ECU. Reports have been favorable for this unit working on boosted applications. This unit DOES NOT adjust valve timing (VVT-i) as far as I know, but also does not conflict with it. The FI/C adjusts ignition timing, but will not hamper the ECU's control of the factory VVT-i system. (Also, at this point the F/IC only has the ability to retard and not advance ignition timing.)
Then there is the Greddy V-Manage. This was designed specifically to be used on Variable Valve Control systems. It appears that this could work for the xB, but the cost is quite high and you would have to build your own wiring harness. It is also pretty unlikely you'd see much if any support from Greddy. To get the full benefit you'd probably be wise to pick up either e-manage or e-manage ultimate so you can do the remainder of the tuning on the motor.

Next we have the Power Enterprise CamCon. This one has probably been used more in the xB community than either of the other two. Unfortunately with mixed results. Some guys claim that it works quite well. Some guys claim it works great for a little while and then the ECU is able to compensate for the modified signals being fed by the CamCon. Still others claim there are never any gains at all.

It might be possible (or even a good idea) to attempt using the Power Enterprise CamCon in concert with the AEM F/IC. Don't even ask me about how to wire, or tune this sort of setup. I'm at work right now and my head would explode trying to run all of the diagrams in my head. If successful, you would be able to control fuel delivery and ignition timing (retard only) with the F/IC and valve timing with the CamCon. I would not attempt doing this on your daily driver unless you are very confident in what you are doing, or have a tuner familiar with both systems.

Header Configurations - Well, this one is a can of worms, that honestly, I'd rather not get into. Your best bet is to do a search online for "header design" and study, study, study. I'll try and keep it simple, 4-1, 4-2-1, short tube, long tube, they all have their place and their purpose. Generally speaking given all other aspects are equal you can expect more midrange power from a 4-2-1 design and more top end power from a 4-1 design. You can't really say one is absolutely better than another. It all depends on you're specific engine configuration and how you plan to use it. Other than that, I said my piece on headers in the initial post. I would say build and materials quality is probably more important for our application, than design in regards to readily available bolt-on headers.
Throttle Body Spacer - I've said it before and I'll say it again. On an otherwise stock 1NZ-FE engine (I/H/E are not part of the engine) there has never been any proof that a throttle body spacer increases power or efficiency. They are great for some vehicles, but of no benefit to us. Others may disagree, but until I see definitive proof, I will hold my stance. Now, if you'd like to use one as a paper weight I would have no objections.

Lightweight Crank Pulley - I guess I was tired last night, since I missed this one. Personally I have mixed feelings about the pulleys. I don't care for the under drive at all, and I am not sure if the lightened units are really of much benefit. Proponents claim that the lighter weight helps you rev quicker and get to the power band that much faster. Opponents will say that you actually move through the power band too quickly with the lightened crank. There is also this issue many have had with the crank pin. Shearing problems have occurred, but it does not mean that it will absolutely happen.

Rods - I would only consider moving to forged rods if I was doing one of two things. Either going boosted beyond 6-7 psi or bumping up the compression with forged pistons. As long as you are in there doing the work on the pistons, it is worth it for the peace of mind the much stronger aftermarket rods provide. If you are staying naturally aspirated and are not bumping up compression, there really is no need for aftermarket rods.

Regarding your comment on Weapon R. Anyone who doesn't think the company isn't a little bit shady needs to take a step back and take another look. I run one of their headers on my wife's car, but I still don't believe all of their claims. What I would really like to see is a shoot out between their manifold and the Dynatek manifold on the same car under the same conditions. If I could get a hold of a Dynatek manifold, I could probably make it happen, as I've got another guy locally who is a Weapon R dealer and has their manifold on his car.

[PCH]

Cool, thanks for sharing that info. I have not moved into doing engine mods yet, but was thinking about trying to tweak timing curve a little.
Now question about cam regrind on 1NZ: What are the stock specs on lift and duration and was the work that you mentioned earlier done to both intake and exhaust cams?

[kev1NZFE]

I'm getting my car dyno tuned in two weeks by a local shop. Right now I'm waiting for my Apexi AFC Neo and custom Boomslang harness to come in.

I'm doing this to squeeze out some extra power out of my car, and to see how much of an improvement my mods have made. Oh, and I'm also running lean. I spoke to Chris from Weapon-R and he said none of the cars they tested on ran lean, so I'm guessing it's just the setup I'm running.

Right now my notable engine mods are:

TRD Cold Air Intake (Modified to Short Ram)
Weapon-R Intake Manifold
Weapon-R 4-2-1 Headers
TRD Axle-Back Exhaust
Agency Power Lightweight Crank Pulley
Ingalls "Stiffy" Engine Torque Damper

So far, the biggest differences, according to the butt dyno, have been from the manifold and crank pulley. Acceleration after installing both mods became much easier. The sluggishness of the xB off the line was something that always bothered me on the drive to work and school. Now, the daily drive is much more fun, especially since letting off the clutch on first gear is so much smoother (you can attribute that to the pulley and Ingalls damper).

I'll post up the sheets when it's done.

--EDIT--
Oops, I meant sloppiness, not sluggishness.

[rton20s]

To PCH...

Honestly, I'm not sure of the specs on the stock cam. But I do have the specs on the regrind from Gude. If I had to guess, the only real change is probably duration. I don't understand how they could get more lift out of a stock cam. Not if all they are doing is taking material off. My understanding is that on a regrind you can change the lobe profile in order to have longer or shorter duration as well as a more or less aggressive opening of the valves.

Anyway, here are the specs on the Gude Cams...
Part Number: SCXBS01
Intake Cam: Lift - 0.420, Duration - 238
Exhaust Cam: Lift - 0.400. Duration - 238
According to the Gude website they include racing springs and shims, the power band is from 3500 - 8000 rpm and the idle is "good."

And as long as we are talking about Gude, they also sell a ported stock throttle body.
Part Number: N/A
Max Dia. @ Taper: 53.3mm
Dia. @ Butterfly: 47.0mm

Gude does not have any pricing listed on the site.

To kev1NZFE...

Thanks so much for bringing up the Apexi unit. As I stated in my original post, I was pretty tired when I was writing it, and I completely forgot about Apexi. The AFC Neo is a basic air/fuel ratio management computer that has a great interface and good sensor monitoring. Unfortunately, it does not do anything to adjust cam or ignition timing.

I'm very interested to see how your dyno tests turn out. It would be great to see some before and after tune dyno graphs. It would also be great to see how the unit behaves in the long run. In other words, how well does it do at tricking the factory ecu after a period of a few days/weeks/months.

You may also want to consider going with at least a cat-back exhaust. If you are happy with your axle back, it would actually probably be pretty cheap to just swap out the mid-pipe after the catalytic converter.

[kev1NZFE]

I don't plan on doing anything crazy with the tune, so a basic air/fuel management system is all I need. I'm just trying to correct whatever the CEL is telling me to. I'll definitely keep you updated on how it goes.

I was thinking of swapping the mid pipe, but it's going to have to wait. My wallet took a good beating with my last mods.

[xb_release_2]

i upgraded to the perrin lightweight pulley at 42000 miles and at 46000 miles later blew a water pump pulley.
warrenty covered it because i took it off, not sure if i want to put it back on, definately made the lower rpms pull harder.
since i have a GReddy SP2 exhaust and a ebay header and it was definately worth installing pull in first is about the same but pull in 2nd and 3rd is what made it much better!
this thread has been bookmarked!!

[PCH]

Gonna post a link to Gude build since it's related: Gude Dyno Numbers...
The cam in that post has different duration but since they never say at what lift they measure it, who knows if it's any different.
Does 1NZ use same stock cams in all applications and years? Any chance the non-emission control markets have better ones?

[TheToaster]

Although more popular in forced induction applications don't forget water/methanol injection. There are many companies out there that provide injection kits....AEM, CoolingMist, Devils Own, and Snow Performance are some of the leaders of that particular market. Any of their universal kits would work. Lower EGT's and lower IAT's in nearly ALL internal combustion engines would free up a few ponies just from the cooling characteristics. Just by bolting the kit in and plumbing the lines you will see nice gains. Now when you have a tuning device coupled with the injection kit of your choice, the injection kit's contributions to the entire system as a whole will allow you to add more Spark Advance to the car (via your tuning device of choice...not all tuning devices allows you to do this) with the end results being even a larger gain in overall power.

Running a mixture of h2o and methanol or methanol "by itself" in the system will yield a higher octane rating in the fuel (the more methanol concentration the higher the octane increases). An important thing to remember is, throwing more octane in the mix without proper tuning will actually make you SLOWER. Higher the octane the slower the Air/Fuel mixture burns during the combustion cycle. If you aren't tuned for this you will actually loose power. Keep that in mind in all your car modding endeavors.

The last and final benefit (not a performance one) of running an h2o/meth injection kit is that it keeps the internals like new! Cant go wrong with that.

[Calesta]

@rton20s 1st post...

1. Short rams are generally better for higher rpms, CAIs for lower. This is because of the tube length and acoustic tuning (if any was done by the manufacturer). You can tune pipe length for acoustic reinforcement based on wavelength length at different rpms. This applies to intake runner length and header runner length too. Example: variable length intake manifold runners. CAIs also boost performance a hair by theoretically bringing in colder, more dense air, but I prefer to take the advantages of both systems by building short ram intakes that are have heat shields to prevent underhood engine temps from affecting the intake charge temps. A look at K&N's FIPK line will show you a good example of this. Too bad they don't make an FIPK for the 1st gen xB.

3. I'd buy the DC Sports header way before any Weapon-R product.

4. NGK Copper is definitely the way to go.

6. A lighter flywheel doesn't really free up parasitic losses- it just acts as a smaller torque capacitor for your driveline. Lighter flywheels give you less delay before the power from the engine gets to the wheels, but they also store less energy so you'll have to manage your throttle a little better on launches and starts from stops. I always like the lightest flywheel I can get that still keeps the engine balanced. I ran a 7.5lb Fidanza on my Civic and it was NICE.

7. I actually prefer to leave something like the axles as a planned break point in the driveline. They're cheap, easy to replace, and have lifetime warranties from AutoZone that are wonderful to abuse. If you beef up the axles, you stand a chance on breaking something even more expensive and a LOT harder to fix- the differential or transmission. Just my preference. Drive smoothly and you won't break your axles anyway.

Heads- Extrude Hone is a pretty safe bet for just polishing if nobody is doing good port jobs yet. Their results are absolutely amazing.


@rton20s later post...

Throttle body spacers- definitely a waste of time. They just increase plenum volume for the intake manifold, which won't matter much until the engine starts "gulping" more per intake event than the plenum can supply. Since injection happens at each port instead of a vacuum draw with a carbureter, the spacer/swirler is pretty much useless.


@rton20s even later post...

You can increase lift while reducing the base circle on the cam by adjusting the cam followers. Adjusting the followers to have the same clearance as stock off the lobe will cause the new grind to lift the valves higher.

[TheToaster]

In regards to extrude honing.... on rough cast surfaces such as a cast aluminum intake manifolds extrude honing is awesome and a pretty much guarantee in power increase.

In regards to extrude honing on cylinder heads, its not ideal. I know you were just referring to this as a next best alternative to actual porting but it should be noted that polishing on the intake port is not the best thing to do, due to the fact that the rough finish on the intake is to aid in fuel atomization. Polishing the exhaust ports would be the only thing worth while to polish.

Which brings me to another thing I see some vendors doing on here (and on other boards)..... and that's actually shaving down the valve guides in the cylinder head so they're flush with the port angle/geometry. This should also be noted that although freeing up CFM throughout the head its not a good idea for street car applications.

Polishing intake ports and shaving down the valve guides seem to be the most common mistakes in regards to cylinder head work.

[Calesta]

Yes, you're correct. Texture on the intake ports helps atomization in most cases... but then the wonderful guys at Extrude Hone should know and tell you that- unless they're just greedy and want to sell you a hone for every surface no matter what. Definitely polish the exhaust to a mirror finish every time.

[TheToaster]

Originally Posted by Calesta

Yes, you're correct. Texture on the intake ports helps atomization in most cases... but then the wonderful guys at Extrude Hone should know and tell you that- unless they're just greedy and want to sell you a hone for every surface no matter what. Definitely polish the exhaust to a mirror finish every time.

Woohoo someone who actually knows a thing or two about cylinder head work.

[PCH]

Originally Posted by Calesta

You can increase lift while reducing the base circle on the cam by adjusting the cam followers. Adjusting the followers to have the same clearance as stock off the lobe will cause the new grind to lift the valves higher.

Yeah, that's how it's done. Duration is usually less because of it and it also makes the opening and closing ramps of the lobe steeper, so the valve moves faster and needs better springs.

[Calesta]

Originally Posted by TheToaster

Woohoo someone who actually knows a thing or two about cylinder head work.

Among other things.

Originally Posted by PCH

Yeah, that's how it's done. Duration is usually less because of it and it also makes the opening and closing ramps of the lobe steeper, so the valve moves faster and needs better springs.

Of course, I was just assuming that the followers in the 1NZ head are adjustable... never been inside of one. I've spent most of my time inside Honda engines plus a few Nissans.

[PCH]

The followers are solid and come in many different heights. So you replace them like shims to dial in the valve clearence.