Pre turbo questions

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Pre turbo questions

Postby sarkazmo5 » Mon Mar 02, 2015 11:58 pm

I have a couple codes my car is throwing. I want to clear these up before attempting to boost.


I have been looking these up, and the 1447 seems most likely to be carbon canister failure, or loose carbon in lines. Anyone find different reasons? I read a trick that you can disconnect the next thing on the evap line from the canister (a valve?) and see if carbon falls out.

For the 0505, likely cause the aicv is dirty or needs replace? I did two different cleaning methods in the vacuum line. There is only a slight idle problem, really not enough to worry about I think. If 750 rpm is normal, I was maybe 8-900? at idle. In drive it is 750. It does dip to maybe 500 currently for a sec when I go from park to reverse after I did this gumout cleaner in the vacuum tube to the aicv trick I read, and it idled at 1200 or so for a day, now back to 1000, maybe under in a few days? The only plan I have is find a few days off, remove entire intake, and inspect all the vacuum lines and aicv.

Last thing, I have some confusion on a couple of boosting things. WD says I don't need a head gasket at 300whp (unless I read wrong) and stock internals are good at same power. Papasmurf says forged internals at 300. Which is it? Tuning is important. I chose Nistune, and their website lists a local shop as an 'official' tuner. The second bit of the question has to do with the tune itself. I am confused about retarding timing, 8:1 fmu, piggyback, stand alone... what is Nistune in all this? From what I understand it can chance timing? It controls fuel so no fmu? I would guess piggyback since it connects to the ecu? With a complete turbo setup, which I am confidant about hardware wise, adding in Nistune is all I need right? No msd, no fmu? (300whp goal, stock internals, will have all the needed gauges, z32 maf, o2, etc).

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Re: Pre turbo questions

Postby PapaSmurf2k3 » Thu Mar 05, 2015 2:38 pm

I'm not too sure about the 1447 failure, but yes, the canister can leak carbon into some of the lines. Not sure which one it is, but feel free to pull them all off to see if there is carbon in any of them.
For the 0505 - if you cleaned the idle control valve, try disconnecting the battery to reset the code. From what you're saying about how it idled high for a day and is now backing down, it may need to re-learn (or re-set) the dutycycle of the freshly cleaned valve.

Stock head gasket is good for 300whp. You CAN get by on stock internals... just know that we have seenc cars fail at 300 (or slightly more) on stock internals. The lifetime of the engine is definitely reduced (unless you get lucky) on stock internals at that power. Don't forget, you are more than doubling the power, increasing heat, etc. If you stick with stock pistons and rods, and your engine blows, please don't come back on here and blame WD or myself for steering you in the wrong direction.
Nistune was a good call. It isn't a piggyback per say, more like unlocking the factory ECU... so sort of like a stand-alone without all the hassle of re-wiring every little thing. It can change timing, injector duty cycle, adapt to different mass airflow sensors, etc. You don't need an FMU, piggyback, or any other junk with it. If you plan on running E85 at some point, ask your tuner. He might suggest just getting an adjustable fuel pressure regulator so you can "shift" your whole fuel curve to adjust for the different fuel.

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Re: Pre turbo questions

Postby AZhitman » Thu Mar 05, 2015 9:37 pm

Here's a build article that covers a "quickie" turbo KA, and a PROPERLY BUILT turbo KA. ... art-1.html

As a hint, the properly-built one is still running nearly a decade later, and made 440whp on E85 at last dyno tune. Do it right, or don't do it. :)

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Re: Pre turbo questions

Postby WDRacing » Wed Mar 11, 2015 6:57 am

You can easily run boost through a stock KA motor. Easily. How long it runs and how well it runs has everything to do with the current shape of the motor and the tune itself. Detonation kills motors. If you're unfamiliar with detonation, also known as knock, you should read this, detonation and preignition.

How you attain 300whp will also make a huge difference on things. What I mean by that is, yes you can make 300whp by just cranking up the boost and adding fuel. But it will be much harder on the motor than if you were to have a proper set of cams, a good flowing turbo manifold, the proper cooling modifications and a turbo that is operating within its realm of efficiency rather than screaming at 110,000 rpm trying to make more boost than it's designed for.

You can do it affordably and make a lot of power if you go about things the right way. To be honest, by the sounds of your first few posts you might want to have your car professionally tuned as that's an area where a novice will do the most damage. Trust me on this, I have blown up all sorts of things being stupid.

When my KA went I knew it had rod knock. I didn't think it was severe enough to lock up the motor, I was wrong and tossed a rod through the block trying to limp the car home. Should have towed it. Expensive lesson learned. My fault, not the motors. In fact, every motor I've popped has totally been my fault. I had lots of money, no kids and access to lots of motors when I was learning though. So unless you're willing to blow stuff up and swap parts left and right, make sure you know what you're doing.

Sorry I'm late to the party.

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