# Sticky  The KA Turbo Thread



## bridrive55 (Aug 26, 2004)

In response to numerous questions about KA24 turbo setups, I have decided to finally just lay it all down for reference. Please don't post in this thread!

We've all heard it before: "I'm getting SR20!" "I'm getting RB20!" Many of us have been through the same tired loop of engine options. There is a plethora of engine swaps available for the 240SX, but there is only one thing that they all have in common: turbo.
All of us want it. The more rich of us buy fancy things like JDM front clips, loaded with RB20DET's, SR20DET's, CA18DET's, etc. Well, some of us just can't afford them. But there is still hope for us.
I love all the KA24's. I think the iron block 2.4 liter stands on it's own, a uniquely American engine in a proud, tall line of fine inline engines produced by Nissan. Being poor isn't the only reason to go KA-T. The ridiculously strong iron blocks and almost 600cc cylinder size create a joyous torquey power band. The enignes are by no means rev-happy from the factory, but with a turbo attached, the combination of low end torque and high end breathing power is absolutely amazing.

The bottom line is, the KA24 is a viable option for turbo, and I feel the best option for those of us who either love the KA or don't have enough for a JDM engine.

*ENGINE COMPARISON*

-"S13A" 1989-1990 KA24E
The KA24E is the single cam ECCS 2.4 liter 4-cylinder engine that accompanied the S13 chassis on it's debut in the US. The engine produced 140 brake horsepower and 155 lb/ft of torque at the crankshaft from the factory, with a compression ratio of 9.0:1. The engine was driven by a single overhead camshaft, making it the only SOHC 240SX motor. It is also the shortest lived motor on the USDM S chassis, making a 2 year run of production. Nissan's ECCS system was used for fuel delivery. The KA24E never did shake its reputation for being a truck motor, but it's also the first KA and part of the 240SX story. It is, all in all, an iron block KA.
The KA24E is a surprisingly viable candidate for turbocharging. There are advantages and disadvantages to the KA24E. Advantages include the top mount fuel rail, which makes powerful top-feed injectors a "drop-in" replacement. Second hand large top-feed injectors are plentiful in the US and Japan, coming from Diamond Stars and RX-7's, as well as others. Fuel injectors of high capacity are easier to find and more affordable for the KA24E than for the later, side-feed types. The KA24E is also not severely disadvantaged due to it's SOHC nature. The KA24E is a 12 valve motor, with 2 intake valves and 1 exhaust valve per cylinder. Camshaft replacement mods are also half as expensive as dual cam engines. The ECCS system is a top-down intake runner design, unlike the KA24DE. The intake runners are relatively restrictive when compared to later engines, especially the S14 intake manifolds, but can still allow for up to 400 horsepower. Fabricating larger intake runners would be simple. In addition, the compression was slightly lower on the KA24E, making it a slightly more viable candidate for increased boost. The most deleterious drawback to the KA24E is the scarcity of turbo manifolds for the engine. This is due to the fact that the exhaust ports are closely juxtaposed in 2 groups of 2 ports, unlike the even spacing of the KA24DE. Fabricating a turbo manifold is not difficult, however, and if you love the KA24E, this is surely your best bet.

-"S13B" 1991-1994 KA24DE
Nissan quickly realized that the 240SX needed to be improved to compete with the American sports cars. The KA24E truck motor was the car's most severe market hindrance, so for the 1991 model year, the 240SX got the new KA24DE powerplant. The block remained similar, but the intake manifold, head, and exhaust structure were remarkably different. The KA24DE is a dual cam version of the familiar 2.4 liter iron block, which sported 155 brake horsepower and 156 pound feet of torque at the crankshaft with a slightly heftier 9.2:1 compression ratio. The torque of the old KA24E was there, but this engine breather better, revved higher, and made much more high end power, exactly what was missing from the KA24E. The KA24DE also has a bit of a bad "rap" for being the Altima engine, but this is notably better than the truck motor, most think.
This engine also has advantages and disadvantages. The KA24DE is a full 4 valve per cylinder DOHC motor. The exhaust ports are evenly spaced, making turbo manifolds easy to fabricate and plentiful on the market. It has a frustrating side-feed fuel rail, which of course lacks the uneven spacing of the KA24E fuel rail, making a retrograde impossible. To it's defense, the 370cc fuel injectors from the SR20DET are a "drop-in" replacement. Companies like Tomei and Denso make much larger side feed injectors as well, and all injectors that fit the SR20DET will fit the KA24DE. The intake design on the KA24DE is radically different than that of the KA24E. The KA24DE features intake runners that flow from below the intake ports, as opposed to the SOHC engine's top-down design. The S13B KA24DE's had a sharp cam profile, more so than the S14 or Altima versions. The intake runners were restrictive, but the S14 intake manifold is a direct swap, and larger intake runner fabrication is again a viable option. The KA24DE shares many of the same problems of it's single cam predecessor, namely high-end asthma, bearings that like to spin, and timing chain guides that become loose and cause a ruckus.
Due to the strong aftermarket support, KA24DE's of all years are generally considered a better starting point for building a turbocharged engine than the SOHC KA.

-S14 1995-1998 KA24DE
The S14 240SX came out for the 1995 model year as a substantial revision to the previous S body. This revision again was in response to the Japanese market, where the Silvia got a new body. In America, the same body came through, but the old engine remained. The S14 240SX had different valvetrain characteristics than the S13B, but only got 1 more horsepower out of the mix. The S14 motor cranked out 156 brake horsepower and 160 lb/ft of torque at the crankshaft from the old 2389cc engine, but had even higher compression: 9.5:1. All of the features from the previous longblock remained the same.
The S14 motors are slightly more powerful than the S13B, but are not different enough to be preferable. The later S14 KA24DE's went to an OBD-II ECU, but this was perhaps the most dramatic change that the motor underwent. All in all, the KA24DE was a remarkably static engine.

All three iterations of the KA block have advantages and disadvantages for turbocharing. In common, all three have weak internals, and all three tend to spin bearings. With stock internals, the KA24DE and KA24E can approach 350 brake horsepower, but staying with 300hp is probably the best idea if you don't want to rebuild your engine anytime soon. It is not extremely difficult to get the magic 300 with a KA-T, but it will take time and money. A properly built KA24DET with the full stand alone fuel management can produce over 700 brake horsepower.


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## bridrive55 (Aug 26, 2004)

*Part 2: Going Turbo*

*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!


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## kaptainkrollio (Jul 29, 2003)

This should be a sticky, great info.

I do have a question though: Rebuild before low boost(7psi) setup or no? I know that is depends on the condition of the engine that you are working with, but what are some of the bare neccessities? I was thinking forged pistons and new rod bearings at least.


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## bridrive55 (Aug 26, 2004)

kaptainkrollio said:


> This should be a sticky, great info.
> 
> I do have a question though: Rebuild before low boost(7psi) setup or no? I know that is depends on the condition of the engine that you are working with, but what are some of the bare neccessities? I was thinking forged pistons and new rod bearings at least.


You don't need to rebuild until you hit the point where bearings start to break or turn. This can occur as high as 350hp, but bearings have been known to turn below that as well. Running 7psi on the stock internals is fine. I run 12.8 psi on my stock internal KA24DE as well, with no problems.


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## kaptainkrollio (Jul 29, 2003)

bridrive55 said:


> You don't need to rebuild until you hit the point where bearings start to break or turn. This can occur as high as 350hp, but bearings have been known to turn below that as well. Running 7psi on the stock internals is fine. I run 12.8 psi on my stock internal KA24DE as well, with no problems.


 Even with 170,000 miles?


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## bridrive55 (Aug 26, 2004)

kaptainkrollio said:


> Even with 170,000 miles?


Lol, you might want to rebuild the bottom end. Those bearings are going to want to spin... Spun bearings are by far the most common KA internal problem. Sometimes the bearings spin or break in half even on naturally aspirated engines, but turbocharging greatly increases this risk. New OEM crank bearings are easy to install and will remove this worry from your mind, at least for now...


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## bridrive55 (Aug 26, 2004)

toofast240 said:


> I am the truth to all this nonsense. I have the truck and the proof that they did put a ka in 90 pickup. Your power fiqures are a lie.
> 
> Please print this hang on your wall its not a lie. :thumbup:


Right, right, the Z24 motor ran through the 1989 model year in the pickup. The D21 pickup got the KA24E for the 1990 model year. My bad.

Power figures a lie? Okay, 2 things. 
1) I've stated before, I went to Nissan Red Stage and wrote down all the horsepower figures and compression figures. That means that if these figures are a lie, Nissan is the one that is lying. I'm not just making up numbers here. There IS a power difference between S13 and S14 KA24DE's. The KA24DE in the S14 is significantly different than the S13 motor. The S14 has an internal coil and different cam profiles. The compression is also higher on the S14. These factors account for the differences in power between the S13 and S14 KA's.
2) Your exact words: "Please print this hang on your wall its not a lie." I'm a native English speaker, but your grammar is so miserable, I don't even know what you're saying. What point are you trying to make? 

Furthermore, why do you care? Do you have a KA24ET or KA24DET? Are you planning on building one? I have a lot more useful information on building a KA24 turbo that I am willing to post. If you have any questions related to KA turbo, please post them in this thread. If you would like to point out errors or demonstrate how bad you are at the English language, please do so in a private messege, and I will do my best to remedy either situation.


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## bridrive55 (Aug 26, 2004)

*Part 3: KA to KA swap*

There are many reasons to swap out your KA. Some of us want big turbo power, others have broken motors, and still others want to be rid of their SOHC headache. I had all three, but regardless of your condition, if you are a 240SX owner, you have probably considered an engine swap. The KA to KA swap is the most viable engine swap option for the 240SX because the motors can be affordably acquired, the KA24's are readily available all across North America, the KA's are great candidates for turbo, the KA has a broad base of aftermarket and OE parts, and the KA to KA swap can be the easiest of the engine swaps. If you learn anything from bridrive55, let it be that any KA24 can be swapped into any 240SX, quite easily.

I'm not going to say that the KA24E is a bad engine. I'm also not going to try to convince 1989-1990 240SX drivers to dump their KA24E's and toss in a DOHC KA. I can tell you that I am very happy that I did, however. The bottom line of 240SX engine swaps is: If you want a DOHC motor, the KA24DE is your cheapest and easiest option.
The KA24DE engines came in 2 distinct 240SX flavors: S13 and S14. The S13 KA24DE came from the 1991-1994 240SX's. The S13 KA24DE featured some of the same style pieces as the KA24E powerplant that Nissan discarded for the 1991 model year; the spark system being more or less similar between the two S13 motors. The S13 KA24DE features an external ignition coil, like the KA24E. The S13 manual ECU's also had a speed governor. The MAF is new for the S13B, however, and very few parts are compatible between the single- and dual-cam KA's. The S14 KA24DE had a wee bit more compression, a different upper intake runner design, slightly less agressive cam durations, an internal ignition coil, and a new valve cover design. OBD-II diagnostic system hit the KA24DE during the S14 production run as well.
Both KA24DE's are good for turbo. The cam duration and compression differences between the S13 and S14 KA24DE's are not, in my opinion, drastic enough to make one vastly preferrable over the other. S13 KA24DE's are generally cheaper, and S14 KA24DE's generally have fewer miles. Buyers on the market for a KA24DE platform generally tend to seek the motor with the least wear on it; one that will be more reliable under boost.
Putting the S13 KA24DE engine into your S13A is easy. All you need is the harness, ECU, and complete motor with subsystems. Power steering lines, radiator, and radiator piping from the S13B will be needed to make the swap direct. Most of the A/C system will need to be taken from the S13B donor car as well. You can fabricate coolant hoses, of course, to fit any radiator. The interior harness connection is plug and play with the S13A interior harness clip, and the DOHC harness fits into the 2 harness clips by the battery tray. 
You can keep your old transmission. The lower wiring harness is compatible with the new S13B wiring harness. In fact, any 240SX transmission from any year is fully compatible with any KA engine, from any year. If you are bolting a manual transmission onto a KA24 that had an automatic transmission on it, you will need the manual flywheel, transmission metal gasket, and engine block transmission mount brackets. Do not use the auto tranny flywheel bolts on the manual transmission. 
You will also need a gauge cluster from a 1991-1994 240SX, with the cluster wiring harness. It's neat to get the gauge cluster from the same car that your engine came from, so that you know the milage of the motor, but it doesn't always work that way. Some people keep the S13A guage cluster, but many functions will not work, including the tachometer. The tachometer signal on the S13A and S13B is different.
The S14 motor is more complicated. Everything is similar to the S13 KA24DE, except the interior harness connection, which is drastically different. Using the S14 ECU with the S14 harness creates a wiring nightmare behind the dash. Every single wire on the S13 interior harness will need to be soldered into a new position on the S14 harness, and many functions still will not work, including the tachometer. The easiest way (the only easy way) to swap an S14 KA24DE motor into an S13 is to use the S13B wiring harness, with the S13 KA24DE distributor, external coil, MAF, and ECU. This is $200 of parts that will save you 50 hours and a huge headache. WIth these parts, the wiring is plug and play like the S13 KA24DE, and you have an external coil, which is easier to attach an MSD box to. This is what everyone who has swapped an S14 KA into an S13 and I would recommend.

I would really love to see a KA24E in an S14, but I haven't seen one yet. You can also swap an S13 KA24DE into the S14, but doing the reverse of the opposite swap; use the S14 harness, MAF, and sparksystem. Whatever your engine swap choice, once you bolt in and wire up the motor, it is my advice to drive the engine around for a few days before going turbo. You will get a chance to notice any problems the engine has, and get a feel for the new motor. I would recommend swapping in a beefier fuel pump and filter (300ZX TT fuel pump and filter work great and are affordable) with any engine swap, especially the SOHC to DOHC swap.


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## bridrive55 (Aug 26, 2004)

*Q45 MAF swap*

I highly recommend the Q45 MAF swap, so I'm posting a link to the thread I made about it. I'll say it again, easier and just as cheap as the Z32 TT MAF swap, and huge performance gains.
http://www.nissanforums.com/showthread.php?t=98568


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## thedaddies (Sep 29, 2003)

The SOHC is a perfectly strong motor as well as the DOHC for boosting though. Let it be said that the current record KA hp is from a SOHC and not a DOHC. 703 rwhp out a SOHC by Ventura Racing (despite that it was in a Toyota Starlet). Of course this is only until Ivan @ Phatka-t.com finishes his drag car.


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## thedaddies (Sep 29, 2003)

To add to what has previously been posted:

There is quite a bit of info here as well, but more is to be found there. Due to a higher populous with SOHC engines.
For starters...

Manifolds: All of these listed generally have T3 flanges on them.

IAP (importautoperformance.com)
JGS (jgstools.com/turbo)
gladmanperformance.com
realnissan.com

Injectors:

Top feed/High impedence
Best average injector size and largest able to run on piggybacks or basic reflash by JWT is 550cc (Good for 350 hp)

Intercooler:

Pick one you like and fab piping for it

BOV:

Pick one you like
Good
JGS
Tial
Blitz Super Sequential
Turbo XS RFL
Greddy Type RS

Wastegate:

Either run a good external, or internal (internal will be cheaper)
Under the good department

JGS
HKS
Tial

Oil lines:

JGS sells them
cheapturbolines.com

Downpipe:

Fab your own here too

Fuel Management: 3 types

Reflashed ecu by JWT

Piggyback

Emanage
SAFC2

Standalone

AEM EMS
Microtech
Haltech
SDS
Link Plus
etc.

Other SOHC products that are available:

Built Block Specifics...

Solid Lifter Conversion (hybridka.com)

Forged Pistons

Arias 8.8:1
Ross 8.5:1
CP 8:1

Rods

Crower KA24DE rods 
Pauter KA24DE rods

Bearings

Clevite are the best from what I've seen and heard

Cams

JWT
PDM
Colt Cams

Valves

Si Valves

Aftermarket Intake Manifolds

No one currently offers one, so it's a one off job

Metal Headgasket

No one currently offers an off the shelf one

Crank between the DE and E are identical as are rods, so any of those are interchangeable. The pistons are interchangeable but the compression will change when that is done.


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## bridrive55 (Aug 26, 2004)

Great info, thanks for it all. A company called ForcedFab has the best oil line kit that I've seen. Very high quality, works for top mount turbo setups, KA24 specific, and very cheap (cheaper than www.cheapturbolines.com).


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## thedaddies (Sep 29, 2003)

Also the SOHC late '88-early '89 motors were 9:1, and the mid '89-'90 motors were 8.6:1 compression. I have both in my garage.


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## bridrive55 (Aug 26, 2004)

*Wiring the Apex'i SAFC-II*

Some peole get hung up about management for their KA-T projects. Is it possible to use anything else besides AEM's expensive EMS system?
Yes, yes it is. If you don't want to shell out huge bucks for the Greddy EManage system with all the subharnesses that you need to buy to make it worth a shit, Apexera electronics makes what is in many people's opinions the best tuning option for the KA24DET. SAFC-II.
Many people think that because the 240SX uses a USDM ECU, the SAFC-II won't work. Well, it will. And it's small, cheap, easy, affective, and even pretty. Coupled with AVC-R, SAFC-II gives you virtually unlimited tuning options. SAFC-II is programmed to accept any Nissan MAFS, so if you use the stock KA24DE MAF, a larger Maxima or N/A Z32 MAF, the even larger Z32 TT MAF, or the insanely large Q45/GTR MAF like I use, SAFC-II will still read the voltage just fine. SAFC-II allows up to 50% correction of the Air/Fuel curve, and there are ways to monkey with it to get SAFC-II to run up to 400RWHP, or so they say.
I've had awesome luck with my SAFC-II. It was simple to wire, easy to program and tune, and allowed me to safely run 15psi of boost on 550cc injectors, with a GTR MAF and a stock TPS. SAFC-II is in my opinion the best tuning option for mid power KA24DET's.
So how do you wire the damn thing? The 240SX ECU isn't in the little wiring diagram booklet. Wrong junior, it is. The 240SX ECU uses the N3-A wiring plot in the SAFC-II booklet. N3-A, remember that.
The SAFC-II comes with a neat little assortment of wiring couplers and joints that should be discarded immediately. Just solder the wires in place, and you'll enjoy years of solid connection. The double ground wire is not a joke, you need to ground the two wires between 1 and 4 centimeters apart. Make sure you do the initial setup BEFORE you turn the engine on, THEN do the knock sensor setup and tuning. The KA24DE TPS is the downward pointing arrow type. The only problem I've seen with KA24DE SAFC-II setups is the Rev sensor. Make sure the tach sensor on the transmission is the same type as the ECU. You might experience problems using a KA24E tach sensor on a later setup, as I did.
Good luck with the tuning! I recommend at least wide band tuning, and use a dynomometer if you can. If there are any KA24DET questions/discussions, please post them here.


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## thedaddies (Sep 29, 2003)

The downside to the SAFC2 is that you cannot control timing with it. So for those that intend to run it, make sure you back off your timing at the distributor at least. That is if you won't purchase a MSD BTM.

There are other standalones available for the 240. There's lots of universal types.
Here's a few

Link Plus
Motec
Haltech
AEM EMS
SDS 
Microtech
Amongst others....


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## bridrive55 (Aug 26, 2004)

On that note, optimal timing is said to be 18 degrees BTDC on KA24DE engines for turbocharged setups. You need to retard the spark at least 3 degrees to fight knock, but 5 degrees is best. SAFC-II comes with a knock sensor voltage reading, and you can program a threshold into it so that an alarm sounds when the engine has too much knock. It's a nice feature, but some people have had trouble with their knock sensors. The MSD timing regulator is best. Greddy EManage allows you to screw with timing as well.


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## thedaddies (Sep 29, 2003)

Autometer narrowband guages will tell you very little about what your motor really is doing. You will need a wideband 02 sensor setup to be able to monitor it. You should have one on any motor frankly. Even a NA motor could benefit from it.


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## veilside180sx (Aug 23, 2005)

Stay as far out of boost as possible. I have to do the same thing to get to my dyno as well. Just make it rich around 4000 to cover your butt. Don't get out of the partial throttle maps on the ecu. That way you really won't be building much boost, if any.

What trim and a/r did you buy for the XS turbo?


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## chrislis (Jun 27, 2005)

I'm only gonna be running about 8-10 pounds of boost, I was told I'll be fine if I drive at about 3-4 grand on the rpms the whole way. I'll pretty much stay 65 mph the whole way up. Now another question, what about the MAF sensor? I heard it will be going nuts not recognizing anything going on.


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## bridrive55 (Aug 26, 2004)

chrislis said:


> I'm only gonna be running about 8-10 pounds of boost, I was told I'll be fine if I drive at about 3-4 grand on the rpms the whole way. I'll pretty much stay 65 mph the whole way up. Now another question, what about the MAF sensor? I heard it will be going nuts not recognizing anything going on.


MAF sensor choice usually goes with management choice. SAFC-II likes the Nissan MAFS. A GTR MAF will handle huge ammounts of airflow (>60lb·min^-1), and the Z32 MAF fits nicely on 3" piping while still being able to process lots of airflow.


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## bridrive55 (Aug 26, 2004)

bridrive55 said:


> MAF sensor choice usually goes with management choice. SAFC-II likes the Nissan MAFS. A GTR MAF will handle huge ammounts of airflow (>60lb·min^-1), and the Z32 MAF fits nicely on 3" piping while still being able to process lots of airflow.


To clarify notation, lb·min^-1 reads "pounds per minute."


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## Nismo14-180 (Mar 31, 2004)

What about downpipe selection? like using a SR downpipe (performance or stock) for a stock T25/T28, would it even fit up to the catalyst converter? 

Maybe I should have asked this on KA-T.org...


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## bridrive55 (Aug 26, 2004)

Nismo14-180 said:


> What about downpipe selection? like using a SR downpipe (performance or stock) for a stock T25/T28, would it even fit up to the catalyst converter?
> 
> Maybe I should have asked this on KA-T.org...


The stock SR downpipe works on Nissan T2s. It's easiest to get high flow stuff from step one, however. Custom downpipes are manufactured that go past just the "elbow" and bolt up to factory S13 or S14 exhaust loci. EBay it.


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## bridrive55 (Aug 26, 2004)

*PICTARS!*

Hey guys, 
I figured all this talk deserved at least a little pic-action. So last summer I spent all my time and money on my project, but I quickly ran dry, and I was going from paycheck to paycheck, putting every penny in my car. I didn't get anywhere near where I wanted to get, and I didn't work out all the kinks, but here's where I was at:

VLSD swap complete: 1995 Infiniti J30
Race clutch
3" dummy exhaust, welded by buddy... Soon to be redone professionally
T04E
Tial 38mm WG
3" FMIC piping
Type S BOV
Big FMIC (never measured it)
550cc galley injectors
Z32 fuel pump
SAFC-II
Q45 MAF (actually an RB26DETT)
Lots of etc.

So it's not anywhere near done, but here's how it looked when we fired it up to run SAFC-II numbers:









From the front: a modified S13A front end that I had laying around. I know it looks stupid, I just wanted to show how sneaky the FMIC is:









This is the engine when I was redoing the spark system, no exhaust or FMIC piping attached:









So it's nothing special, but when it's done it should be nice. I don't aim for more than 325whp, because it's scary. There's a 2" spring drop as well, and shaved everything. Stock rims and such. I plan to paint it this summer, and get a real exhaust. We did actually port the WG into the exhaust to make it nice and quiet, because I like the _whooooosh_ noise. I ran it at 15psi for a little while, but 7-10 are what it's usually at.
The main point of this project was the engine swap. The turbo kit just kind of fell into place. I really just wanted to wire in an S14 motor because my KA24E spun a bearing.


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## bridrive55 (Aug 26, 2004)

Looked up the MAF codes and it is actually from a VH45, not a GTR at all. Stupid importers don't really know where their parts come from. Anyways, just wanted to set that straight.


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## bridrive55 (Aug 26, 2004)

*DANGER: KA leanout!*

Hey guys,
Considerable evidence points to the conclusion that the stock KA24DE OBDI (and KA24E) oxygens sensor band is exceeded by the fuel/air ratios generated when a turbocharger generates atmospheric pressure (manifold neutral pressure, reads 0psi on a vacuum gauge). This preboost spool occurs during regular driving every time the throttle plate is not fully open and manifold (post throttle body) pressure is between 4"Hg and 3-4psi boost. The factory ECU map cannot compensate for the increased air, and unilinear A/F curve adjustments will not compensate for this! Preboost leanout will hurt your KA, so I strongly advise all turbocharged KA's to take extra care in enriching the fuel/air mixture in that pressure range. I recommend usining wideband oxygen sensing and an earlier fuel pressure onset if possible.

The OBD-II oxygen sensors have a wider band (wider voltage range), and this might compensate for preboost leanout. Once again, this is only a consideration on turbocharged vehicles.


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## bridrive55 (Aug 26, 2004)

*Oil restriction*

Oil starvation and bearing oil seal hyperpressurization are two leading causes of premature turbo failure, when douchebaggery and idiocy are not considered causes of failure. Ensuring the right pressure for your turbo by variable resistance would be the most reliable method of controlling bearing lubrication, but it would be difficult to monitor the pressure adequately right before the oil inlet on the turbo. I've kicked around the idea of a rising-rate resistor linked to a vacuum line (boost line) that would open a valve under boost and permit more oil flow to the turbocharger, but my first design using a modified fuel-pressure regulator failed. The best way remains unilinear resistance of a large aftermarket oil line.
This unilinear (constant, as opposed to variable) resistance is usually achieved by placing a NOS jet in the oil feed line right before the inlet to the turbo. Other down-and-dirty methods include the tapered head of a BIC ball-point pen and the actual piece that I use, which is a selectively cut plastic tip from a micropipet, a device used by molecular biologists (such as myself) to accurately aspirate and deliver small quanitities of liquids. This is a polystyrene cone that I cut at two sections to create a tubule that supplies the peripheral resistance needed to save the turbo bearing seal from hyperpressurization. I recommend the NOS jet route. Do NOT run a turbocharger (especially a T2) without oil resistance of some sort.
Oil starvation can be prevented by monitoring oil lines carefully. If an oil line becomes kinked, the turbo seal will dry out and the bearing will blow. This destroys the turbocharger. Too many good people have sold their cars after the frustration of blowing multiple snails.


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