The goal of this is to achieve a better basic understanding of going KA-t for people who want cheap KA-t boost. so not everything will be 100% accurate, but enough to give a good idea to new ka-t-ers. this is my first big post, and i just thought it would be helpful for new members with questions on boosting a KA for cheap...

Numbers are not solid and I am typing this from my own understanding and reading of stickies, so feel free to correct them for me! and if any questions, ask them so i can add on to this. thanks!

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1) What to understand before boosting

Feel free to read my webpage I made for an old class to get a general gist of what turbo charging is and how it generally works here -

http://www.freewebs.com/tsaice/turbo101.htm

Hopefully after reading my crappy webpage you now have a better understanding of how turbochargers operate. HOWEVER, keep in mind, adding power isn’t as easy as just slapping a turbo on a calling it a day. When adding power, you introduce more stress + heat to your engine, and you will require a form of fuel management/tuning (will be discussed further in along with exceptions, etc.), possibly upgraded cooling systems, and a bunch of other items to prevent your spent money from blowing up in your face. Also, Be sure your motor is also in good condition prior to adding performance modifications, otherwise doing so would only make them worse faster.

2) How much boost can I run?

This question is often asked and is really an open ended question because it is affected mainly by the type of turbocharger you use, its trim, and your engine size.

For example, a smaller turbo (T25) and a bigger turbo (say T3/T4) can both run 8psi, but have a major difference between each other. The reason is because you have to visualize the volume of air being moved.
________________
|||||||||||||||||||||||||>>> imagine this as a t25 pumping air at 8psi
________________
|||||||||||||||||||||||||>>> Now this is a T3/T4 pumping air at 8psi.
|||||||||||||||||||||||||>>>

the rate of passing a certain point can be the same speed, but the physical volume of air moved is much more with a bigger turbo. If you still don’t grasp that, think about a T25 as a 2 lane highway at 80mph, and a T3/T4 as a 8 lane high way at 80mph. which one gets more cars from point A to B at the same velocity?

But that doesn’t meant to just get the biggest turbo you can find and slap it on. Which leads us to the next question…

3) What turbo should I use?

What turbo SHOULD you use? This depends on your goals. Before going KA-t, always to always have your goal in mind. Try not to come into this forum telling us you want a 6000hp super drift machine that can also do a 6sec quarter mile, fly, go on water, and be your daily driver all at the same time. (Keep in mind, this also applies to people who as “which (part) should I buy?”) Be realistic. Is this going to be your track car? Street driven fun car? Beater car? Point A to B car?

Remember, you can’t have it all, even though we all would like to. General turbo sizes and characteristics are:

Smaller turbos (ex: T25/28)
quicker spool on our ka-ts
Power band in the low mid-mid revs
not as wide a power band as larger turbos
almost non existent turbo lag

Medium Sized Turbos (ex: T3, T3/T4(?))
May have a tad bit of turbo lag.
wider power band in the mid-mid high revs
higher peak power than smaller turbos
More power without sacrificing too turbo spooling fun on the street

Larger turbos (ex: T61)
Noticable turbo lag
Narrower power band in the high revs, but with high peak power
I don’t think it would be fun to drive it on the streets, but suitable for drag racing I guess

Keeping that in mind, you also should know what the efficiency of turbos are. Usually smaller turbos start to get out efficiency at the mid 13-15psi ranges (example is the sr t25) which means more stress on the turbo, hotter air, and no benefit to you. As turbos get larger, they can pump more with less stress on them.

Metaphorically speaking, A smaller turbo pumping more air is like a tight squished 2 lane highway with all the cars going 120mph to get as many cars as possible to somewhere as fast as possible. Accidents are bound to happen.

A larger turbo is a 8 lane going 120mph, but has more space, and can move the same amount of cars to a place in the same time as the 2 lane, but less stressful as there are more lanes to travel in. So define your goals, and go for them!

4) Can I use this brand? How much should I spend?

As you jump into the world of vehicle performance, you will sooner or later start finding yourself going to eBay and trying to get used parts to save a few so you can have a car, pay for gas, and maybe eat.

Again, what to skimp on, and what not to skimp on ultimately depends on your

Budget
Goals

Also remember the triangle rule for performance
- 3 choices: Reliable, Cheap, Fast. Pick two, and the 3rd one will naturally apply
ex: If you can it to be reliable and fast, it wont be cheap. Get my point?

Doing performance cars to your cars are not “investments” and can and usually do get expensive.

As for parts and brands, some people are all about “you get what you pay for”, and some people don’t care as long as it gets the job done. Its really personal preference, but there are some general rules to follow

eBay:

this place is filled with great deals form genuine greddy parts to made in china turbo kits and coilovers. In general, FMICs, IC piping, Strut bars, Intakes, Exhausts, used parts, and stickers are safe to buy without too much worrying. Other items such as coilovers, BOVs, WGs, springs, turbos, and turbo kits are really hit or miss. Some people have great luck with eBay turbo kits, some blow in 30 miles. But in general some parts are really “generic” and will get the job done, but some may disagree. So decide accordingly to your budget and don’t always get caught in the hype of brand names. Why pay 800$ for a Greddy FMIC kit when a 300$ eBay “godspeed IC kit” can do the same thing? but really, buy by on your own discretion. (btw, from reading around, the bottom mount t25 manifolds for ka’s mostly seem to be pretty tough)

For more on Ebay turbos, see  http://forums.nicoclub.com/zerothread/321821

Name Brands:

Now this is when this hobby gets expensive. But think about it. Sometimes when you pay a premium for name brands such as AEM, Greddy, Tein, Stance, etc. those items are guaranteed to work and have more research behind them. Also, when things go wrong, its usually easier to get them fixed through a warranty or good customer service (which is what you’re mostly paying for). Some things just work better if they have a good reputation, such as Garrett turbos that are guaranteed to not blow on you in less than a month. Sometimes paying for peace of mind is a good thing. Especially if you are hardcore on performance and reliability. But remember, its not going to be cheap.

But also keep in mind that some parts are really what they are. For example, an intake really is just a pipe with a filter on it. You can make a CAI yourself if you are so inclined for 50$ instead of paying for a 250$ shiny red one with a sticker on it. So remember, shop smart!

Forums FS section:

most of us don’t have the money to buy new parts, so Forum FS sections really are a goldmine. For some people who don’t want to spend a fortune on a turbo kit/parts, time and searching on a forum can help you find great deals. Reliable used sr turbos can be bought for cheap off people who upgrade their stock sr turbos. 370cc sr injectors are also a great drop in for the KA. Other items that can be found for great prices can also be found in forums, such as used IC kits, FMUs, SAFC, gauges, wheels, tires, suspension, stock parts, etc. so try not to overlook forums when looking to buy parts!

So the wrap up is, there are many places to buy parts, but really; shop smart, and see what your budget can or cannot do. Keep it realistic. Also, try to avoid impulse buys or whatnot. Example, you may want an exhaust and intake, but end up having to ditch the intake when you turbo, or not like the exhaust since its just loud and you’re still NA.

Many people ask what to do when they want just a little more power from the NA KA. Lets face it, the KA24DE isn’t too great NA, an NA build is $$$ we don’t have, but when turboed it’s fun. The best advice is to save up and just turbo it. Also, know what you should and shouldn’t skimp on. In this case, try not to skimp on the turbo and fuel management if possible!

5) My friend says…

“eBay parts sucks, cause my friend says so. Also you need to rebuild your engine with these super expensive parts, and get a SAFC tune and these Mad JDM TyTE PARTS YO!” this is an exaggeration, but I’m sure we all have heard something like this before. Sometimes people have things to say but nothing to back them up except for what their friends who read it off a blog of their best friends grocers’ daughter’s boyfriend who is a secret master drifter in Japan.

When choosing items to buy, try to get good feedback from people who have actually had experience with what you are looking at. There are plenty of knowledgeable people here who can help you out with such things, but it also doesn’t hurt to SEARCH. Also, not all forums look out for what you want.

here is a perfect example of when I started.

Quote, originally posted by abc123omg »

you guys are really helpful! when i posted this on another forum they all said things along the line of "Its always a good thing to retard timing at any boost level.." "put sr injectors in with a maf and tune and do a head gasket and studs minimum." "dont expect your setup to last long" any validity in what they said? anything i should worry about? anybody here had a setup like this last long (2yrs ish?) with no issues? the other forum is creating a lot of doubt in my mind...

Reply was

Quote, originally posted by WDRacing »

The thing about other forums is quite simple...they suck. Here at Nico we're more of a family, we may fight and argue, but more often then not we're helping each other do what WE want, not what THEY want. Obviously you're on a budget. Which means your best bet is to keep things as simple as possible. By that I mean use items and methods that are proven. The FMU is an excellent choice because it's cheap and allows you to run a small amount of boost with no tuning. A method and item that has been used for 8-9 years with great success now. Anyone that says different simply does not know what they're talking about. Is it the best option...no, but we aren't speaking in terms of best, we simply want to run a little bit of boost reliably on a budget. With the boost kept under 7psi you don't need to retard the timing if you use premium fuel, 91 at a minimum. Head gasket and studs? Tell that dude to kill himself...nuff said about that. We have guys pushing 500whp without ever having lifted the head once. All of the items you listed I have to assume are in good condition. If they aren't, then they may fail, but that has nothing to do with the amount of boost you're planning to run nor the combination of parts you have chosen. In the sticky there is a link to building a Over boost Protection device, read it and build it. That way even if you get a boost spike, the car will shutdown rather then blowup, which is a big plus in my opinion. Be careful with the boost, it's more addictive then heroin. You'll be tempted to turn it up...don't. Unless you come back here and do some serious mods first. WD

That being said, let me just mention NICO is a great forum, and have awesome moderators with much knowledge! no BS!

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Fuel system/tuning/setups

Ok, so you need fuel, air, and spark to run a car. And you need proper tuning to achieve the best performance out of your car.

Here are some basic guidelines for turboing your KA-t. I will concentrate mainly on people who are BUDGET boosting and with setup recommendations, and try to give the best recommendations to people for boost for the cheapest, assuming their motor is in good condition and holds good compression. But don’t hold me to this since luck does play a large role in what works and what hurts.

What you NEED to do a BUDGET KA-t (with recommended parts)

Turbo Manifold (bottom mount t2 eBay manifolds aren’t bad) 100-200$
Turbo (recommend a used sr t25 or if your feeling lucky, an eBay turbo) 100-200$
Misc Lines ~100$
Down pipe ~ 150$
Piping to TB
Wastegate (if not internal) -varies
Blow off valve (not “needed” but high recommended to extend life of turbo, some ebay ones will work well if you know what to do) ~50$+ from ebay to others
Bigger exhaust (recommended 2.5”-3”, can custom, ebay, or go HKS!) varies from 200$+ give or take a few depending how smart you shop.
Intercooler (highly recommended, doesn’t hurt to have one) can be bought for cheaper on eBay. 200-300$
Also think about replacing your clutch when you start getting close to 200hp

Fuel management options

Keep Stock 270cc injectors (not recommended) OR SR 370cc( will require tune) ~100$
FMU(better than nothing, may need to retard timing depending on boost run)~100$
SAFC(better than FMU)~100-200$
Standalone (good but also pricey) – ehh , not too sure..
ECU tune (best option) ~170$(Emance)-500$(JWT and Enthalpy)

Remember, if you look around, boost can be had for cheap. I got my setup together for only 650$(sr t25, FMIC, lines, piping, manifold, tune, etc). Jumping on the deal at the right time can save your wallet. Prices above are assuming you just buy parts without haggling and such..

Nice thing to know:
- Stock KA24DE internals can take up to 400-450hp before you decide to swap out internals. But remember, it is an average. Some have crapped out before that mark, and some have gone over too. But most have hit it.

- Your TUNE will make or break your KA. KA-t can be reliable (Emance, JWT, and Enthalpy are recommended)!
(Testimony on KA-T reliability here http://forums.nicoclub.com/zerothread/351769) and tuning stuff here (http://forums.nicoclub.com/zerothread/252368)

- Don’t buy into the sr vs. ka debate. Both are great motors and make good power. We just have more torque =). And why throw away a perfectly good motor? (KA-T WHP and PSI poll http://forums.nicoclub.com/zerothread/38554)

- For safety reasons, we recommend running a performance fuel pump with any FI(forced induction) setup to avoid maxing out stock fuel system parts. Walbro’s are cheap ~90$ and are a great upgrade.

- FMU + stock injectors = not tunable.

- FMU + non stock injectors = might as well ditch the FMU and get some injectors and tune it. But it’ll help the injectors “not max out”

- anything NOT stock injectors+ walbro = HIGH RECOMMEND A TUNE (SAFC, Emance, JWT, Enthalpy) otherwise its pretty much useless. TUNING ELIMINATES NEED FOR FMU!!!!!!!(some people don’t know that)

- average gains are 10whp per 1psi boost.

-stock injectors are 270cc

- FMUs are not a “true tune”. Fuel pressure adjusts in a linear fashion to just dump fuel to prevent you from blowing your engine. They can work great, but just aren’t the best and can be too rich sometimes and too lean later.

-SAFC Tuning is a huge learning curve, and also a huge gas curve. And when you are done, the tune will never be as good as a ECU tune. I have heard stories of people tuning on a dyno with an SAFC and spending hundreds, but never achieve a good tune. Not the tuning item of choice. However, SAFCs are helpful when fine tuning an existing ECU tune.

-ECU tune. These things are solid and are services offered by JWT, Enthalpy, and Emance. You may read a lot of questions on it, but Emance is a true bang for your buck. I believe it’s the cheapest of all options and are tailored to your setup and was recommended by WDracing to me when I went KA-t.

So….What you can get away with….
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Very Low boost. (1-4psi) (stock MAF) (up to 180ish whp)
- stock injectors and fuel pump, no tune (not recommended, but has been done)

- stock injectors and walbro, no tune (not recommended, but has been done)

- stock injectors with FMU and walbro, no tune (a little better/safer)

- sr 370 cc injectors with fuel pump and safc (probably best of all options)
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Low Boost (4-8psi) (stock MAF, but can upgrade to Z32 maf too, up to low 200s whp)
- stock injectors and stock fuel pump (don’t even do this, might as well pull your engine now and give it to me)

- stock injectors, FMU, stock fuel pump (not recommended, can max out pump/injectors, but has been done)

- stock injectors, 8:1, walbro (better, but risks maxing out injectors, but has been done on budget and some ppl sport this daily,
see  http://forums.nicoclub.com/zerothread/341680)

- sr 370cc injectors, walbro, safc (much better than previous options, but tuning can be difficult. Some people run pig rich, some people just have really bad tunes)

- sr 370cc injectors, walbro, ECU tune (best and safest option)

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Frequent Issues when turboing
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I will try to add more common solutions to common problems associated with turboing of NA engines.

1) My car is Stalling/Bogging on Decel
A quicky solution is provided thanks to DevilMB3017. Ill try to do more research on this and update as much as i can!

Quote, originally posted by DevilMB3017 »

Okay. Quick lesson time. A BOV is in place to prevent compressor surge. This is what that means. You are driving down a street, boosting. You come towards a redlight and let go of the gas pedal. The throttle body closes, and this causes the air from the turbo to build up pressure, and because the turbo doesn't just stop spinning, it will still build. Now this air has to go somewhere. A blow-off valve is a valve that 'blows off' this extra air. If not for a BOV you get compressor surge, which is the return of this air back into the compressor - in the OPPOSITE direction, which can wear a turbo or break it VERY VERY quickly. Some turbos are more sensitive then others, but why chance it? To do this the BOV uses a vacuum source. When it has vacuum, it stays shut, allowing air to go into the throttle body - and into your engine. When it no longer sees that reference vacuum from an intake source it knows your no longer on the gas pedal and it opens to allow the air out - because this is at a higher pressure then the vacuum, so the BOV knows whether to open or closed. Now, some BOVs, specifically the HKS SSQV uses a diaphram in this sense with no adjustment. Some BOVs, like yours, have a spring in it for partial throttle applications. When your boosting a little bit, and only on partial throttle, you are close to even on the vaccum and the boost. This would make the BOV start to open, even though that air is supposed to be going INTO your engine, it is going out the BOV. This will cause problems, so you use the spring to adjust how much boost/vacuum ratio it needs to open. Finally.... With a MAF on a draw through setup, which is where it is on your turbo, it meters the air, then it combines with the turbo and goes into your throttle body. The ECU uses this and the O2 sensor to determine fuel required to burn. When the BOV goes off, the ECU thinks this air is going into your engine, which is why you need to recirculate it AFTER the MAF, but before the throttle body. The close to the throttle body the better iirc. With a 'blow-through' MAF setup, you can place the MAF on the cold side of your intercooler, right before the throttle body, and this would allow you to vent the BOV to the atomsphere because the ECU will never know that air was there. This is a little more complicated in tuning, according to some people. Hope that helps and gets added to a "noobs read" thread...I'm looking at your abc123omg

Hopefully this thing I have written is helpful to people on a budget wanting boost. If you crave more boost, do more searching and you will find your answer. Let me know if there is anything I can change to help people get boosted for cheap. Any constructive input is appreciated!

BTW, i havent ventured into the high boost territory yet, so my knowledge is limited on that stuff...

Modified by abc123omg at 5:19 PM 8/4/2008

Modified by abc123omg at 4:25 PM 8/9/2008

1991 Nissan 240SX S13 - KA24DET 5 Speed
Arias Pistons | AMS Rods | Crower V2 Cams | Cometic HG | Ferrea Valves | ARP Studs
JGS Manifold | T3/04E | Greddy FMIC | HKS SSQV BOV | Koyo Rad | FAL E-Fans
JGS Wastegate | 640cc Injectors | AEM TruBoost | Enthalpy ECU | PLX Wideband
Megan Racing Coilovers | RUCA's | Tension Rods | Subframe Collars
J30 VLSD | One Piece Driveshaft | Spec Stage 3+ Clutch
5Zigen FN01R-C | Falken RT-615 225/45/R17
337rwhp @ 18 PSI/11.5AFR [DynaPack Dyno]

RaymondMotorWorks@gmail.com

great

Quote, originally posted by 240lookis »

there is no trap. only free candy.

Make a build thread to discuss everything about your kit.

Going to ebay, must order parts now

But bear in mind the drive train is a lot different in that scenario. The transmission, axles, etc. can't take the same amount of abuse the rear-wheel drive counterparts can. 250-300 fwhp would be awesome out of a Altima though!