kike85

hi there, i have an 02 is300 automatic. pretty much stock ive only added : knn filter, removed the catalystic converters and installed an o2 sensor simulator. my question is..... i want to make it faster but i dont know what would give me the more bang for my buck. to get some pulleys and some headers for the car or to get a pi torque converter? what would be better?

LexusGSXR

headers and exhaust is good to start...good gains.. SRT intake is good gains..

underdrive pulley will damage motor..

torque convertor is good for manual.. stalls and so forth..

mex lex

iTrader: (4)

Mazzuri header

LexusGSXR

Read this all the way thru... very intresting for IS newbies!...


Scenario 1. I want more power, enough to feel, but I want to stay quiet and have no headaches like CELs or black soot coming from the exhaust.
Scenario 2. I want a lot more power, I still don’t want any headaches like CELs and I still want to keep the car fairly quiet.
Scenario 3. I want as much horsepower as I can economically get, I still don’t want CELs, but noise and tuning are okay.


Scenario 1:

Intake
Joe-Z (or PLP SFI, though this is no longer manufactured, they still sometimes pop up for sale in the member sale/trade forum) upgraded intake pipe and a drop-in air filter (consult the IS300 Bolt on Upgrades Catalogue Sticky)
Price
$99 plus $8 shipping from the my.is store
Installation
30 minutes, easy enough for anyone to install on their own car
Why?
Both the Joe-Z and PLP retain the stock airbox, they merely replace the pipe from the airbox to the throttle body. The OEM pipe has a resonator and baffles which quiet the intake down some but also slows and disrupts airflow through the pipe, limiting the amount of air available for combustion in the engine. Both of these upgraded pipes are straight through and make for less resistance. Retaining the stock airbox does two things; it keeps the intake fairly quiet and it also makes the modification less noticeable to anyone inspecting your car, especially if you stick with the anodized black version (call it CARB unnoticeable instead of legal). The aftermarket drop-in air filter will also improve air-flow. There are a couple types of these, foam and cotton generally, many of the cotton ones are cleanable and re-oilable. Personally, I recommend avoiding the re-oilable ones as excess oil can damage the mass airflow sensor (MAF) in the intake pipe.

Header
TurboEast/OBX/Toyomoto/Alphaworks/Megan Racing/any ebay header, there are only two designs for all these headers, long runner and short runner, they are basically one-offs of each other, many of them actually made by the same company. Make sure the header comes with nuts, bolts and gaskets. You will also need an o2 simulator to trick the ECU into not realizing you removed two catalytic converters
Price
Last header I saw on ebay was $190 plus shipping (new)
O2 simulators are usually ~$30-40
Installation
If you aren’t afraid to work on your car, get a friend and expect to spend 3-4 hours doing this, it is fairly easily done with a lift, though many do without one. The o2 simulator will require that you cut and cut and solder some wires. If you don’t do it yourself, expect to pay $200 to $300 to have a shop install the header for you.
Why?
These are all pretty generic headers and there aren’t many differences between them. Theoretically, the short runner designs will make more power down low and not as much up high in the RPM range while long runner designs will gain more up high, though there isn’t anything to prove that among these headers. The o2 simulator is required because there are 4 sensors in the exhaust, 3 on the header and 1 on the y-pipe that measure oxygen and fuel levels in your exhaust to determine if your catalytic converters are properly functioning, two are ahead of the cats, then the one after them should detect lower levels because of the upstream cats. Because we are removing the cats, this will not be true, however, the o2 simulator will imitate the “everything is fine” signal from the o2 sensors so the ECU doesn’t know there is a problem.

Y-Pipe
Keep the stock one!
Why?
The stock y pipe will put some restriction in the exhaust which will keep some backpressure around to make more torque. An exhaust can actually be not restrictive enough; some of the people on the forum have actually lost power when they added a y-pipe to their exhaust system. Keeping the stock y-pipe will also keep the last of the stock catalytic converters, this will clean up the exhaust so you don’t get the black soot commonly seen on the rear bumpers of cars without catalytic converters. All of this together will keep down the volume of your system as well.

Exhaust
Whatever you want, all of the exhausts for the IS make about the same gains whether they are cat-back or axle-back. Pick your exhaust out based on the sound you like, sound is a subjective property, what one person likes, another may find loud and “ricey.” Once again, check the IS300 Bolt-on Upgrades Catalogue sticky for ideas, it lists 8 cat-back and 9 axle-back systems.
Price
Depending on the exhaust you choose, anywhere between $300 and $600, people switch exhausts like crazy, check the member sale/trade forum for some deals
Installation
Also easily installed, get a jack, a 14mm wrench (longer the better) and 30 minutes to put on a new exhaust (a penetrating lubricant like PB blaster might also be necessary if your bolts are stuck).
Why?
Whether you decide on cat-back or axle-back, the rear section of the exhaust does more for the sound of your car than it does for power, most make 5-8 horsepower, but every exhaust sounds different. In my opinion, you can’t go wrong with a Tanabe, Borla, or L-Tuned, these are all on the quieter end of the spectrum and all produce a deep sound, though the Borla and L-Tuned are both discontinued and very difficult to find.

Results
Results will depend on whether your car is an automatic or manual as well as the dyno but should be in the 185 to 195rwhp range, lower end for automatics, higher end for manuals. Stock autos should dyno in the 170-175 range and manuals should dyno in the 180-185 range, so you are looking at 15hp or so worth of gains at the wheels.

Conclusion
Joe-Z intake - $107
Whatever header you get - ~$210 depending on shipping
O2 sensor - $40
Exhaust - $300-$600

Self installed – $657 to $957
Shop installed - $857 to $1257


Scenario 2:

Intake/Header/Y-Pipe/Exhaust
Stick with the tips for selection 1, we’ll just add some stuff to your setup to get a bit more power.

Exhaust Cam Gear
Pick one, any one, they all do the same thing, once again, check the IS300 Bolt-on Upgrades sticky for what’s available, 5 cam gears are listed there.
Price
$150 to $200 for the gear itself
$100 to $150 for tuning
$250 to $350 total project cost
Installation
You can do this installation yourself, but it is difficult and needs to be tuned to get any gears. Many shops will install it for you if you are having them tune it for you.
Why?
An exhaust cam gear is a bit of a “sleeper” mod, it won’t make your car any louder, it won’t change the sound, and you won’t even see it because of the cover over the cam gears, however, it is still good for 8 horsepower or so. The cam gear allows the angle of the entire exhaust cam to be changed relative to the crank position, usually around 4 degrees retarded on the IS, though it varies and this is what the tuning is for. This does not change how long the exhaust valves are open, only when they are open. As far as tuning is concerned, most shops charge in the area of $100 to $150 an hour and damn near all of them have a one hour minimum charge, they will do a couple dyno runs to find what setting the cam gear makes the most gains at and set it there.

Air/Fuel Ratio Tuning
Apexi SAFC II (Super Air Fuel Controller) or SAFC NEO. (newest versus old model, same company, same product line)
Price
$300 to $400, shop around online, there are so many different prices on different websites
$100 to $150 for tuning
$400 to $550 total project cost
Installation
If you aren’t afraid to solder, you can do this yourself following the directions. Otherwise, expect a shop to charge $100 to $200 to install it, not including tuning.
Why?
The air/fuel controller allows the amount of fuel being sprayed into the engine to be changed, the SAFC NEO allows fuel corrcection at 16 points throughout the RPM band (The SAFC-II allows for +/- 50% correction in 1% increments at 12 points). From the factory, the IS is tuned fairly conservatively, it runs pretty rich, with more fuel than is needed injected into the engine. Now you can use the SAFC to help the ECU compensate for all the parts you have installed as well as tune it leaner (closer to the perfect 14.7 stoichiometric ratio for complete fuel burn) as you run leaner, the fuel will burn hotter and more completely, delivering more power, you don’t want to be too lean however, or the extreme heat will start to damage your motor. Theoretically, leaning out the mixture would improve your gas mileage, however you will probably find yourself driving the car harder to use the added power and the sound of your intake and exhaust and won’t actually see any difference.

HINT
The exhaust cam gear won’t take an hour itself and the SAFC probably won’t either, to avoid paying the 1 hour minimum twice, go get both tuned at the same time.

Results
Once again it will depend on your car and the dyno, but you can get up to 195 to 205rwhp, a gain of 20-25 horsepower at the wheels over stock.

Conclusion
Parts from Scenario 1 - $657 to $957 or $857 to $1257
Cam Gear - $150 to $200
SAFC - $300 to $400 or $400 to $600
Tuning - $100 to $150 (if you use the hint)

Self Installed - $1,207 to $1,707
Shop Installed - $1,507 to $2,207


Scenario 3:

Intake
Swift Racing Technologies (SRT) high performance intake with R-ECU or AAFC as SRT now calls it*
Price
$450 with free shipping straight from SRT*
Installation
Fairly easy to do if you can follow directions, though you will have to solder the R-ECU to some wires in the factory ECU. Expect to spend about 45 minutes on this installation.
Why?
The SRT is without a doubt the intake with the biggest gains for the IS. It uses a massive 3.5” intake pipe to get the best airflow of all the intakes. This 3.5” diameter pipe is also what requires the R-ECU, the R-ECU adjusts the mass airflow (MAF) meter’s signal to compensate for the increased pipe size that the MAF is in. It also tunes the A/F ratio in much the same way the SAFC controllers do above, though it is not user tuneable. The R-ECU tunes at 350 points across the RPM and load ranges to best exploit the performance of the intake.

Header and Y-Pipe
Mazzuri Super Header and Y system
Price
$650 shipped
$40 for a dual output o2 simulator
Installation
As with the header in scenario 1, the Mazzuri Super system can be installed yourself with a jack, a friend, and a couple hours. Once again, it will be $200 to $300 to have it professionally installed.
Why?
The Mazzuri Super exhaust system was entirely designed and constructed by my.is member and supporting vendor danielm. It was designed for the sole purpose of getting as much power as possible out of a header and y-pipe system, the result is a system with an equal length header, no catalytic converters and that makes far more power than all of its competitors; it dyno’d 24whp and 28wtq gains on a stock automatic transmission IS. An o2 simulator will be necessary to tricking your ECU into believing the catalytic converters are still functioning.

Exhaust
As with scenario 1, pick your exhaust based on the sound you like.
Price
$300 to $600
Installation
Once again, 30 to 45 minutes, some penetrating oil like PB blaster, a 14mm wrench, a jack, and you’re done.
Why?
The Mazzuri header and Y are LOUD, most people stick with quieter exhausts and some have an extra catalytic converter or resonator welded into their exhaust system. All the exhausts will make about the same power so head over to the Mazzuri sound clip thread in the Mazzuri Super forum under the forum sponsors section to get some ideas.

Exhaust Cam Gear
Choose any of them, they all do the same thing, they are just different designs, some different numbers of bolts to hold the adjustment, but it shouldn’t matter if it is properly tightened.
Price
$150 to $200 for the gear itself
$100 to $150 for tuning
$250 to $350 total project cost
Installation
You can do this installation yourself, but it is difficult and needs to be tuned to get any gears. Many shops will install it for you if you are having them tune it for you.
Why?
An exhaust cam gear is a bit of a “sleeper” mod, it won’t make your car any louder, it won’t change the sound, and you won’t even see it because of the cover over the cam gears, however, it is still good for 8 horsepower or so. The cam gear allows the angle of the entire exhaust cam to be changed relative to the crank position, usually around 4 degrees retarded on the IS, though it varies and this is what the tuning is for. This does not change how long the exhaust valves are open, only when they are open. As far as tuning is concerned, most shops charge in the area of $100 to $150 an hour and damn near all of them have a one hour minimum charge, they will do a couple dyno runs to find what setting the cam gear makes the most gains at and set it there.

Tuning
You have a big choice here, either a SAFC-II or SAFC NEO or, for more money but more control, a Greddy E-manage Ultimate piggy-back system.

Apexi SAFC II (Super Air Fuel Controller) or SAFC NEO. (newest versus old model, same company, same product line)
Price
$300 to $400, shop around online, there are so many different prices on different websites
$100 to $150 for tuning
$400 to $550 total project cost
Installation
If you aren’t afraid to solder, you can do this yourself following the directions. Otherwise, expect a shop to charge $100 to $200 to install it, not including tuning.
Why?
The air/fuel controller allows the amount of fuel being sprayed into the engine to be changed, the SAFC NEO allows fuel corrcection at 16 points throughout the RPM band (The SAFC-II allows for +/- 50% correction in 1% increments at 12 points). From the factory, the IS is tuned fairly conservatively, it runs pretty rich, with more fuel than is needed injected into the engine. Now you can use the SAFC to help the ECU compensate for all the parts you have installed as well as tune it leaner (closer to the perfect 14.7 stoichiometric ratio for complete fuel burn) as you run leaner, the fuel will burn hotter and more completely, delivering more power, you don’t want to be too lean however, or the extreme heat will start to damage your motor. Theoretically, leaning out the mixture would improve your gas mileage, however you will probably find yourself driving the car harder to use the added power and the sound of your intake and exhaust and won’t actually see any difference.

GReddy E-Manage Ultimate
Price
Shop around, the best I saw was ~$500 for the unit
$285 for a plug and play harness (I really recommend this, it makes installation much easier and also makes the unit much less permanent, if you have a problem, simply unplug and plug everything back into the stock ecu rather than having everything spliced and soldered)
$200 for a PLX wideband with Bosch wideband o2 sensor (I like the PLX because it is a fairly inexpensive but capable unit, others will work as well), you can buy this and fairly easily tune the system yourself or you can pay someone else to tune the EMU.
$200 to $300 for tuning if you don’t do it yourself
Installation
If you get the plug and play harness, it is simple to do yourself, just follow the directions and plug it in, if you don’t be prepared to spend several hours splicing and soldering. If you have a shop install it for you, it will be more than the plug and play harness cost, suck it up, buy the PnP harness and do it yourself. If you get the PLX wideband to tune yourself, it will need a power source and you will connect the white analog output wire to the input on the E-manage Ultimate.
Why?
The benefit of getting the PLX or other wideband o2 sensor and tuning yourself is that if you change your setup in the future, you can tune it yourself once again rather than paying a shop to tune for you every time you change something. If you so choose, the EMU will even self-tune to target air/fuel ratios you input using the wideband o2 sensor to detect the A/F and make changes. This feature is good to get the unit tuned into the neighborhood on the rich side and then make fine tuning adjustments yourself if you so choose. The benefits of choosing the EMU over the SAFC is that you have this self tuning feature, as well as the ability to make changes to the ignition timing (you can advance timing some to squeeze some more power out of the engine) as well as the ability to raise the rev limiter. Dasgalloway has been running a 7500RPM rev limit on a stock head and he is supercharged. You can raise the rev limit and tune up there to keep making power above the stock redline, which will allow you to make the 0-60mph run without shifting to 3rd and run the ¼ mile strip without shifting to 4th, shaving time off of both acceleration benchmarks. All of this allows you to maximize the power you get out of your aftermarket modifications.

*Bargain time -- If you use the E-Manage Ultimate or SAFC to tune, you can use them to compensate for the SRT intake rather than using the R-ECU which comes with it, try to find an SRT intake in the member sale/trade forum without an R-ECU for a cheaper price

Results
As before, the results will depend on your car and how aggressively you have the EMU tuned as well as the dyno, but look for 215 to 225 horsepower at the wheels.

Conclusion
SRT Intake - $450
Mazzuri Super system – $690
Exhaust - $300 to $600
Cam Gear - $250 to $350 total including tuning
SAFC - $400 to $550 total including tuning
or
EMU - $985 self installed and tuned or $985 to $1085 tuned professionally

Self installed w/ SAFC - $2090 to $2640
Self installed w/ EMU - $2675 to $3075
Shop installed w/ SAFC - $2390 to $3040
Shop installed w/ EMU - $2875 to $3375

Obviously all prices and gains are estimated, dyno results will vary, you can do better than all of these prices if you shop around and/or pick up used parts from the member sale/trade forum. Good Luck with your modifications. I take no responsibility for anything you do to your car following these guidelines.

ZippyGuy

iTrader: (9)

Great write up, not just for an IS but for any Lexus owner

Kaydee

I don't think manual cars can be equipped with a torque converter

KOOLFELLA

iTrader: (34)

So here is my experience..... I previously owned a 02 IS3 5sp Modded with Toyomoto Headers, SRT Intake with tuned ECU, Greddy Evo2, Underdrive Pulleys with Cams, No Cats(Straight Pipe), other Mods as well, but no Torque Converter & I was able to pull off on my friends who owned other IS3's as well as BMW's!!! Never had it dynode but def felt the power difference as far as reliability never had a problem after the Mods were installed (Got a Bomb Mechanic!!!!) any questions @ all feel free 2 ask me!!! Good luck with ur Mods my dude!!!

superduner

the IS300 i bought came with megan header. does anyone know if those are carb legal here in california?