thanks to 170k240 for the suggestion. i helped oversee this when it was created, it's an actual solidly put together list.

all noobs read this first!

These are the Prerequisites to building a DOHC Turbo. Together we will go through typical setups from mild to extreme to reach the power goals you desire. These are lists of typically used items that are easily attainable by the average person. All setups should have the Air to Fuel Ratio verified on a dyno with wideband or at very least on a track using an in-car wideband setup (NO watching the standard O2 signal and calling it good). If your using pump gas and seeing air to fuel ratios more lean than 11.8:1-12:1, some rethinking on the tuning/fuel setup will be needed. A narrowband guage(typical A/F guage from Autometer for instance) is not complex enough to be a real indication of the ratios inside your combustion chamber.



Very Mild Build: around 180 rwhp

Turbo Manifold
Blow Off Valve
Turbo (T25)
Downpipe 2.5" is perfectly fine
Pipe to connect turbo to throttle body

Fuel Control:
FMU (not recommended, but doable) Raises fuel pressure per boost to make injectors flow more than normal.
SR 370cc Injectors. These can be found at places found at the bottom)
Apexi SAFC2
Greddy Emanage


Mild power adder, say you want around 200 rwhp.


Turbo Manifold
Blow Off Valve
Small Intercooler (potentially get away with a side mount)
Turbo T25/T28/14B, etc. Smaller T2 setups. Usually will be internally wastegated.
Downpipe 2.5" is perfectly fine
Replacing the Exhaust is starting to be very necessary at this stage, so I would start to shop for that as well.

Fuel Control
SR 370cc Injectors
Apexi SAFC2
Greddy Emanage
Back off base timing at distributor or MSD BTM

Average: 300 rwhp to 350 rwhp, you have to start to expect a little more lag. This is about the perfect "street car" limit. No race gas, just good honest street car fun that is fully capable of bring home a 12 second timeslip on a good run.

Turbo Manifold
T3/T04E .50 Trim compressor, .60 trim compressor housing / Stg 3 (aka TA31) turbine wheel, .48 to .63 A/R exhaust housing. Internal wastegate optional but not recommended.
Downpipe can still be 2.5", but this is as far as I would want to push that.
Front Mount Intercooler (FMIC) It's time to upgrade to a larger front mount as the larger will push more air than the smaller sidemount can cool.

Fuel Control
550cc Injectors
SAFC2 to control your fuel injectors, along with the stock ecu.
MSD BTM At this stage I would be running the BTM to control timing retard.
Reflashed ECU-This can be a DIY thing with Megasquirt Tuning or a JWT.
Z32 Maf is required, as the stock Maf stops being able to read at around 260 rwhp.
Wideband O2 Sensor should be installed for tuning.

Block Internals
This is where I would start to consider it necessary to replace you pistons.

Above Average: 350 rwhp to 425 rwhp

Turbo Manifold
Blow Off Valve
T3/T04E 50 Trim .48/.63 or slightly larger turbo, this is where I would start to make the switch up to an external wastegate. You have the option to reroute it back into the exhaust, or merely "dump" it out into the open. "Dump" is usually a mini exhaust in the form of 1.5" piping routed out to the open.
FMIC Larger is starting to be necessary. Typical for setups from here on, are 12"x24"x3" for the core.
Downpipe 3", at this point I would switch to the larger downpipe. You can probably get away with it at 2.5", but it will be causing a little bit of backpressure. Moving to 3" piping as quickly as possible is what you want though. Usually it is necessary to have the first bend 2.5" to clear the steering shaft though.
Exhaust 3"

Block Internals
At this stage you'll want to "build" or fortify your block to better handle boost. Previous to this you can walk the line, but here and forward I find it necessary to do so.
Forged Rods
Forged Pistons
Stock Crank
Plus your typical rebuild items.


Fuel Control
Standalone fuel management is recommended at this stage in the game and is absolutely necessary at the next. These allow you control not only very large injectors, but the tuner to have complete control over both timing and fuel.
720cc Injectors.
Wideband O2 Sensor is necessary for tuning.

Wild Build: 425 rwhp to 600 rwhp. Lag is obviously going to be much more apparent, full boost isn't going to happen until around 4000-5000 rpms or so. Once spooled it will pull very hard.

Turbo Manifold
Turbo T3/T61/SC61 or GT35R seem to be the typical turbo's in the area. External Wastegate is your only option that should be considered.
Blow Off Valve You'll want a good performing more expensive blow off valve to alleviate reverted air when the throttle body closes from pushing against the compressor wheel.
FMIC the 24"x12"x3" Core's are still effective in this range.
Downpipe 3" is still capable of handling these power levels
Exhaust 3" or larger

Fuel Control
720cc-1600cc Injectors
Standalone Fuel Management
Recommeded to switch to Map instead of Maf for reading airflow.
Wideband 02 Sensor installed and wired into standalone for adjustments and monitoring.
Dyno tuning is very valuable.

Block Internals
Along with the previously mentioned internals I would add these to the list
Cams (per your discretion)
Build your head as well
Valve Springs
Valve Retainers
ARP Head/Main Studs
Cometic Headgasket or similar


Absolute turbo necessities...amongst the aforementioned goodies above.

Oil Lines (Picture of good return location)


Fuel Pump:
The stock pump is decent but not intended for such use. For Walbro 255's being as cheap as they are, anyone turboing their vehicle should upgrade previous to turboing.

Boost gauge

Here's lists of aftermarket products that are currently on the market

Turbo Build Parts:

Turbo Manifold (Exhaust Manifold)


Ground Zero Motorsports



Full Race



Peak Boost (release date TBD)

Revhard

Turbo240.com



JGS Precision

Realnissan.com

Import-AutoPerformance.com



Nizzx.com



SSAutochrome (not recommended)


BOV

Tial
Greddy RS
JGS
HKS SSQV

Wastegates

Tial



JGS



Turbonetics

Block Internals

Pistons: Can be accomplished one of two ways, by purchasing ones that are made for the E with their intended compression ratio. The other is to use DE pistons and subtract a full compression point to equal the difference between the E and DE head. (ie 9:1 DE pistons will be 8:1 in an E)

Arias 8.8:1(DE)
Wiseco 9:1(DE)
JE 8.5:1
Ross 8.5:1(DE)
CP 9:1(DE)
Supertech 9:1

Rods: Any rod that will fit the bottom end of the DE will work with E as well.

Crower
Pauter
Carillo
Eagle (release tbd)

Bearings

Whatever your preference is for rebuilds. Mine is Clevite.

Headgasket

Cometic

Valves

Supertech Dual Valve Springs
SI Valves
Ferrea Valves

Retainers

Supertech Titanium Retainers

Cams

PDM Racing
Nissan Motorsports
Colt Cams
Crower
JWT Technology


Typical Injectors Used on DOHC

SR 370cc Injectors

SR Upgrade Injectors are available in various sizes between 550cc-720cc as side feed, anything larger usually you'll want to switch to a top feed fuel rail and injector combination.


Injector Resistors (To alter low impedence to work with a high impedence ecu)

JWT Technology
JGS Precision
_________________

 

So you got a KA and you want some more power out of it? Here's some popular modifications that can be performed. You don't have to do all of these, and not all of these will necessarily give you a noticable gain, but this is the list of available parts that can be swapped out for "better" aftermarket units.

First up, maintenance issues:
-Fuel filter
-Oil changes
-Transmission and differential fluids
-Coolant flush/change
-Battery
-Bushings
-Brake pads (rotors if needed)
-And any other issues. Take care of these. Or don't read on.


We'll start with the basics.

Intake
-This is the easiest and simplest mod. The simplest is to drop in a K&N panel filter as a stock replacement. Secondary methods involve removing the stock airbox and using an adapter on the mass air flow sensor, or MAFs, to attach a conical shaped filter. This will give you some small gains, and a noticable change in engine sound. Growly! Don't forget to peel back the fender liner on the driver's side and remove the stock resonator box and the ducting with it. It's probably filled with dirt and leaves anyways. The full intake systems, such as ones from Ebay, Injen, or AEM, include the cross over intake pipe as well as the filter and MAFs adapter. Some, like Injen, have a cold air extension that places the filter in the fender well for cooler air temps...these help the most, but the gains are still only a few horsepower. Be sure the one you buy has the nipples welded on for the stock hoses your car has connected, such as the idle valve. Depending on your year, there might need to be hookups for the charcoal can (EVAP) and AIV (which is the small black box on an S13 near the stock header). Do note the AIV system uses UNMETERED air, so if you hook it back up, put a small breather filter on it, or hook it up BEFORE the MAFs...or leave it open.

*Also, a custom intake that routes to the battery tray area can be made if the battery is relocated to the trunk. The wiring harness will have to be peeled back to free up length of wire for the MAFs to reach over to that side.

Exhaust
-The exhaust is usually the 2nd mod, or in some cases the 1st. It's preference really. Exhausts are chassis specific, so it does not matter if its an SR or KA exhaust (CA exhausts are different I believe). Most KA exhausts are available in the 3" variety, and there really is no loss running 3" on a stock KA, over the few selections available in 2.5". By the way, 2.5" is about 65mm and 3" is technically 76.3mm, but most are listed as 80mm. Exhausts are usually from the catalytic converter back, with some exceptions being just the "axleback" section (just the rear muffler and short piece of pipe with it), and a few systems include a test pipe as a replacement for the cat. Exhaust selection is totally user preference, canister style (like stock) or an N1 style (angled up and out) are both able to make similar power. Exhausts with intermediate resonators will be slightly quieter, and the size of the tip will affect noise to an extent, but they'll mostly just attract cops and ricers' attention.

Test Pipe (or High Flow Cat)
-Being in a lucky state like Florida, we don't have any emissions testing, for now. However, technically it still is illegal to tamper or remove an emissions device from your vehicle, but enforcement is lax, and a cop is more likely to bust on you for tint or exhaust rather than leaning down to see under your car. The stock catalytic converter likely doesn't work much well anymore, unless it has been replaced. Cats in general are large restrictions, and replacing them with a "test" pipe, which is just straight, is commonplace. High flow cats for those who need to have emissions friendly cars or something are available, but are a bit pricey. On S14's the cat might be built into the lower header pipe, and the original cat location is actually a hollow piece (long story). These usually don't run too expensive and are nice to have, since stockers are just rusty and no one likes dealing with nasty rusty bolts.

Header
-The last link in the breathing puzzle, as far as parts that bolt on outside the engine. These are usually 4-2-1 configurations, which are good for maintaining the responsive, torquey powerband of the KA, while allowing it to breathe up top. They'll allow you to retain your EGR if you want as well. On S14's, you might lose your cat, so if you're worried about that, look to the section on cats/test pipes.

Moving on, some shorter tidbits about parts (since im getting tired):

Emissions systems
-If you want to remove emissions systems, you can. The EGR can be blocked off, or totally removed. Same with EVAP (charcoal canister), just be sure to vent the line coming from the gas tank, away from the engine bay and under the car so it doesnt smell like fumes all the time. The AIV and SCV (butterfly valves) on an S13, be sure to remove all the components. *Expect check engine lights* These will not affect how the car drives, if you have everything capped off correctly.

Throttle Pulley
-Currently the only one is the Agency Power one. It is smaller and lighter, to help with throttle response. It says it wont work with cruise control, but it can be if you use the spacer correctly. Few reviews on these, but some say there is noticable 'fun feel' increase, as the throttle opens faster, but you wont actually gain power.

Engine and transmission mounts
-I put this here because chances are, your mounts suck and your engine rocks like a wooden dingy in 6 foot waves. Harder the mounts, the more the vibration, rattling, and noise. Nismo, Megan, or JGS rubber mounts will do the trick for the street.

Crankshaft pulley
-A lightweight crank pulley can free up a few horsepower. There will be debates about the absence of the rubber damper from the stock pulley, but many people run them without problems. If you can find a set of the discontinued Unorthodox Racing pullies for the alternator, water pump, and power steering pump, snatch them up as those are a great look and a little lighter than stockers.

Electrical fans
-Removing the stock clutch fan makes the KA not sound like a truck engine anymore (though it was a truck engine 2nd). Using altima fans is a cheap and effective way to do this.

Lightweight flywheel
-Same concept as the crank pulley. Fidanzas are good and have replaceable friction surfaces. Jun also makes one, harder to find, but even lighter.

Aluminum driveshaft
-Even more so the puprose of the flywheel/pulley concept. Lighter rotating mass does seem to help alot on the KA's response.

LSD
-Limited slip differentials will help put the power down, but arent required. R200v diffs from a J30 or LSD equipped 240 are cheap and if you find one with good mileage on it, they are good enough for all purpose street driving.

I will add more later, such as cams, and some other tidbits. Feel free to add your own suggestions for n/a KA stuff.

 

I found a cool write up on the ka-t setup
good info for you guys that lack the knowledge of the ka-t..


Turbocharging a KA24
Turbocharging a naturally aspirated motor is nothing short of a complete reinvention of the motor. Turbocharging the engine means replacing vast ammounts of the fuel sytem, exhaust system, and intake system. It takes time, money, effort, and ingenuity. People are often deceived by cheap turbo kits, not realizing that turbo setups are incompatible with stock fuel systems. When you do piece together a turbo kit, keep in mind your goals, and then go from there.
Companies like Greddy sell complete turbo kits for the KA24DE, with injectors, intercooler piping, downpiping, and even management. I feel that this is not the best option because of the price involved. For the same ammount of money (over $3,000) you can piece together a kit of much greater potential. However, a full turbo kit is the easiest option to acquire, and by far the easiest to install.

KA turbo setups
There are basically 2 fundamental turbo manifold designs to choose from: top and bottom mount. Top mount turbos are often the larger turbos that won't fit below, and for the KA24DE are typically T3 flange. The bottom mount manifolds are in the style of the JDM motors, and are typically T2 flange.
Choosing between a large T3 flange turbocharger and a smaller T2 flange setup is often a matter of goals. The best of the T2 turbos can support big power, but the larger T3 or T4 turbos simply produce more volume at higher boost levels. Some good T2 setups include bottom mount GT28R setups, which are relatively affordable and provide big power. A stock Nissan T25 is probably the most affordable option, if you are going for low levels of boost. On the T3 side of things, TD04 turbos are readily available in the US, coming from Diamond Star Motors. The TD04 is a quite small T3, and doesn't provide much more flow than the stock Nissan T25 that was used on the SR and CA motors. Larger T3 and T4 turbos are available at more expense, but the possibilities are endless. T3/T4 hybrids are a great midrange option, and come as large as .83 A/R. I personally use a T04E, which is quite large. Even larger T4 turbos come in sizes up to 1.04 A/R and beyond. Selecting a turbo is purely a matter of preference, goals, and money. If you aren'tplanning an engine rebuild, don't invest in a massive T4 turbo, but rather go with a more affordable bottom mount T2 setup.
Most turbo units are internally gated, but some use external wastegates to regulate turbo pressure. External wastegates are generally more common on larger turbos like the top mount T3's. External wastegates are louder, but more expensive.

Turbocharger support
Along with the turbo, manifold, and wastegate (if applicable), many other accesories are needed to complete a turbo setup. Turbochargers are incompatible with stock fuel systems. An intercooler, intercooler piping, blow off valve, downpiping, oil lines, injectors, fuel pump, and management are necessary to complete a turbo setup. A front mount intercooler is by far the best and easiest option for intercoolers. They are also inexpensive. Intercooler piping needs to be welded, but universal kits are available for just over $100. Blow off valves vary in design and performance, but mount on to the upper intercooler piping and slough turbo pressure when the throttle plate is closed. Downpiping is easy to fabricate, and any exhaust shop can do this inexpensively. Oil lines are pricey but necessary for turbo installation.
People often supplement their turbo setups with accessories such as turbo timers, but these are unnecessary. Replacing the small 240SX MAF with a larger MAF is a good idea for higher flowing intake, and is necessary for some management options.

Fuel systems and management
Fuel systems and management are by far the most variable and tricky part of a KA24 turbo build. Injectors are the first step. Although it is technically possible to run a turbocharger on the stock KA24E or KA24DE injectors, a minimum of 370cc/min is recommended for any turbo setup. In the KA world, this means SR20DET injectors for the KA24DET crowd. The SR20DET injectors are 370cc and are easy to find from people who upgrade. They can be acquired for around $100. For the KA24E, the smallest injectors that are readily available are the DSM 440cc injectors. People often upgrade to much larger RX-7 top feed injectors, which came in many sizes ranging from the popular 550cc type up to 760cc. Aftermarket fuel injetors for both fuel rails are available as well, with companies like Tomei, Sard, Denso, and MSD. Aftermarket injectors are quite expensive, but are obviously very large and easily available. I personally think that injectors from other cars is the best way to go for a first step. After you have the injectors, a larger fuel pump is needed. The Z32 300ZX fuel pump is a common mod, and can be purchased from salvage yards or on eBay. Walbro 190 and 255 lph fuel pumps are also commonly used. It is common to replace the restrictive 240SX fuel filter with the better flowing Z32 fuel filter as well.
Management is needed for the new air/fuel mixture that is present in turbocharged motors. Management options are diverse. The cheapest option is the fixed type FMU (fuel management unit) which mechanically provides a constant air/fuel mixture. These are the most affordable way to provide fuel to a turbocharged engine, but are not the best. Digital options are the next step up, which include SAFC-II, AFR, and E-Manage. These are not terribly expensive, and provide the best fuel management for the money. These units digitally manage fuel flow, and provide excellent variability for the money. The next option is a chipped ECU. Jim Wolf Technology is the most famous provider of this service, but these are quite expensive and not user-reprogrammable. The biggest option is, of couse, stand alone fuel management. Stand alone is a complete ECU replacement. Companies such as AEM sell their EMS units which provide exactly what the name promises, All Engine Management. Stand alone is quite expensive, but can support extremely high horsepower applications while providing the greatest level of tuning flexibility.

Piecing together a turbo build and it's components is all a matter of goals and finance. It's easy to get way out of hand with it, but I tell people that they can assemble a KA turbo for $2,000 if they play their cards right. Building a turbocharged motor is one way to reinvent the 240SX and turn it into what it perhaps should have been from the factory: a turbocharged, iron block 4 cylinder with limitless possibilities. Good luck to all who venture into the land of KA-T!

 

heres something that people ask a lot about when going ka-t... tuning!!!!

- Buy a wideband meter!! With an indash display.
I can not stress this enough, even if you take it to a dyno to have it tuned everyone should be monitoring their AFR on the street as well. Various factors can change AFR from the street to the dyno. Also if things go wrong you will know.
AEM wideband gauge, Innovative LC1 w/ the XD1 gauge, PLM300, etc. are all good units.

- A knock monitoring device is key. Listening for knock is pointless when by the time you can hear it on the outside, its too late.
The TXS Knocklite (included with the DTEC units or available separately) is a relatively new unit that can be programed for your particular engines noise profile via the stock knock sensor or any bosch knock sensor (the ford focus knock sensors are really affordable).
Alternatively a mic. pre-amp and headphones can be used (a knock sensor is just a microphone).

-Do not just whip-out a calculator to figure out some kind of base correction for larger injectors and think your finished. This hardly ever works correctly do to the various effects of MAF volts on actual injection time, -27% may drop dutycycle 50% which would cause the stock ECU to go crazy. This is WHY the WB meter is #1 . And its always better even at idle to start a little rich.
Based on my exp. if you want to figure out a number to start tuning from here's something that will get you in the range. The old method of trying to use % of injector increase will generally be too much. From my various tunes on various injector sizes this will put you a bit closer-
(old inj size) / (new injector size) = A
1-A = B
B*0.40*100 = % to take out (negative)
example-
270cc / 440cc = 0.613
1 - 0.613 = 0.387
0.387 * 0.40 = 0.1548 *100 = 15.48% which you would input as -15.5% into your low throttle correction fields.
This is pretty close to my settings on my 440cc /stock MAF tune.
Different injectors styles will have different response times (charge time for the coil) so settings will vary (Again do NOT just input estimations and expect it to be perfect).
Since the KAs are all factory setup for N/A AFRs it necessary to rich en up higher throttle areas that can see boost. Even on a .50 trim T3/T04E .63A/R boost can be had at around 25-30% throttle so those areas above that will need to be richened up. A decent starting number would be +10% from the idle setting (for ~8psi of boost). This should make for a rich starting point depending on the setup (AGAIN do NOT just input estimations and expect it to be perfect. Having the right tools to tune it in properly it what its all about).

-Timing
Timing is ALWAYS a concern with piggybacks. Some piggybacks have timing adjustment built in but most do not. For those that don't, MSD BTMs are nice for in cabin control and it will work at multiple boost levels (unlike dist. retarding). But basic retarding of the distributor is a decent low budget option, the only real differences would be not having different timing retard at different boost levels. But if your only aiming for one boost level and don't have any over boost conditions there's not a lot of difference.
Setting up timing is a matter of avoiding knock. The ECU will happily give you plenty of timing if knock isn't present. If knock is seen, timing goes bye-bye. There's been a lot of discussion of MAF signal reductions giving timing increases. Even with injectors as large as 630cc injectors I have not seen anything that a couple degrees of dist. retard wouldn't have fixed. If your just retarding the disty, your overall timing is going to be lower everywhere anyhow. Therefore fixing any possibility of increased timing.
Now that we have that out of the way, on to tuning timing.
This is where a knocklite comes in really handy because the ECU will retard timing before the knock is audible. Start out with significant timing retard and get a decent AFR tune (don't spend too much time for now, leave it a little bit rich). Then start making passes advancing a small amount each time (if your using a BTM, maybe a degree if your using a timing light). When you finally see a little knock, back up a notch and reset the factory computer. Its very important to reset the ECU when knock is seen because the ECU will start retarding. Unplug the 2 connectors at the battery or pull the battery ground for ~10 seconds then reconnect.
Once settled on a timing setting, the final AFRs can be tuned.
-Airflow meters
A meter swap isn't aways needed. If you have a nice flowing MAF like the S14 one you may actually leave it. The ECU will give maximum dutycycle before the MAF signal maxs out. And with large injectors you will always be taking away fuel until your injectors are tapped out. So basically even if the MAF is maxed out the ECU never sees that much voltage.
And the S14 MAF provides better signal than a larger MAF. Its actually kind of nice to have a stead MAF signal to adjust, makes it more predictable.
The only difficultly is if you wanted to run multiple boost settings on one map. Whatever maximum boost the car is tuned at is all the airflow its going to delivery for. There is nothing else to tell the ECU that airflow has increases after the MAF hits its limit. But there happens to be a work-around. Basically instead of using TPS signal to tell the piggyback what to do you install a suitable MAP sensor and wire its signal to the TPS input.
This actually does wonders for the response of the whole system.
Its really only functional for systems like the E-manage or DTEC-FCs that have multiple throttle ranges. Using a 2 bar map makes it very simple, at 0 psi it should show 1/2 throttle, 7psi 3/4 throttle, 15psi full throttle.
It gives air flow correction based on manifold pressure vs RPM, PERFECT!
The driveability of a normal N/A MAF and boost tunability of MAP.
-Air intake temp. sensor
To keep the ECU informed of the actual temp. entering the engine the AIT sensor needs to be in the cold pipe or in the cold side intercooler tank.
Ideally it should be located in the cold pipe, outside of the engine bay to avoid heat soak to the sensor. Just reading open air temps doesn't really tell the ECU much.
- Tune it properly!!!!! So many people botch the tuning and then blame the piggyback for various reasons when things go wrong. Then others (author included) take the time and care needed to do it right and it works. Either pay for the dyno time or datalog passes down a straight stretches of road. But don't just ask for somebody else's settings and figure your good to go. Paying for a "TUNED" ECU may take some labor out of the tuning, but all setups need to be custom tuned for good consistent results.
<12.0:1 / >11:1 under boost is the goal, don't be scared to take pass after pass to make a nice flat AFR line. 11:6-11.8:1 I veiw as the ideal goal. Also don't make huge jumps when tuning, start plenty rich and make smaller and smaller adjustments as you go. Sometimes as little as 0.2% can make quite the difference.


GOOD LUCK AND HAPPY TUNING!!!

 

deff something that a lot of people need:

HOW-TO: Fix Your Timing Chain Rattle: Nissan Articles: Nissan Forums / Infiniti Forums - NICOclub

 

aww, no all motor write-up?

 

thanks dude, good stuff.

 

so i didnt read anything about rebuilds... i might have skipped over, but i have a s13 with 130000 miles. no rebuild when i want to go ka-t?

 

rebuild first. the headgasket will go within um.... when you back out of the garage