PC111 & Standard Injectors ?

[Lorcan]

Are you asking us or telling us?

[Eckhard]

They are OK. I have some of that impedance myself in the basement waiting for me to work on the project. mine are also 350 cc/m

[Würstchens-Turbo 810]

Are you asking us or telling us?

@Lorcan = i ask :-)
@Eckard = thanks

[Charlie @ Evergreen]

Are you sitting comfortably? Right, then I'll begin

Once upon a time, there was an old fuel injector, made in the 1980s. Its insides were heavy, and it was slow to open. So a big bad ECU was developed to JERK that fucker open with a high current, like 4 amps, then hold it open with, say, 1 amp. This was called a "peak and hold" circuit.

Many years later, way after Fabio was born, lighter, faster, cheaper injectors were made that could be opened and held open by a small current, say 1.5 amps. The circuits for these were cheap and easy to make, and were called "saturated" circuits. This is what we all use today in modern bikes, and what the PC uses.

The PC doesn't really care what signal it receives, it's only going to use it to time when the injector opens and closes anyway, but it will give out a low-amp saturated circuit, because it's only a baby device. This might, or might not, be enough to jerk open the nasty old, stock, injectors. But it might also make them slow to open. The amount of time spent opening and closing is called "dead" time, because the injector can't flow the correct amount of fuel while it's doing this. If the injector doesn't flow enough fuel the engine could run weak, and you may not be able to compensate enough by using magic, or by altering the numbers in the PC map. This could make bad things happen to the engine.

Use modern injectors like the grand old wizards though, and you can be fairly sure everyone will live happily ever after

I know you said DON'T explain it, but tough shit

wow..this is Priceless!!

[Lorcan]

I may have had a beer or two when I wrote that...

[VinoBassi]

Sounded like a professor of science telling his students off..SHIT HAPPEN if you ask for explanation I reckon

[Charlie @ Evergreen]

Hell you should have a couple every nite then

A lot to digest on this fuel system and get some bearing. Keep boost @ 15 or under and save for the PC & Injectors seems to be the key to running 20lbs safely with a good tuned & running engine.

[Lorcan]

You can go the old school route of juggling fuel pressure, TPS and resistors etc and it does work after a fashion but the more you turn the boost up the more you will find you are battling injectors that are too small and a fuel curve generated by the ECU that is moving further away from your target lambda. I'd say 140-150hp on the stock injectors is doable, above that you should be looking at larger injectors and a PC as per the Route to Power.

[Charlie @ Evergreen]

ya...I have read myself into oblivion the last day when I can get on and saw how the ECU can only handle so much also...have 290's in it and it was a bitch getting the idle with a good dark plug to run around to tune it. So I bought a PC3 USB today second hand....injectors next... I do not plan on going even with the 810 over about 180 to 190...so should I still look at the 370s with the PC3???

For now will be running the stock top end at 14.5lbs....don't know if you recommend the 310 or 370 is what I am wondering Lorcan??

[Lorcan]

No point in going any smaller than 370cc, there is no advantage and you only want to map it once.

[Charlie @ Evergreen]

I should get it dyno'd old school..but jeez spending extra $$$'s is a waste..except for the guys that go with the charger...but then again..they should all be using a PC from what your saying

[Charlie @ Evergreen]

Very good then..thank you...didn't know if the 370s a bit much for stock top end with a bigger breather feeding the lil monster...

[Lorcan]

Nah, the PC is quite happy taking out as much fuel as is necessary. Jeff ran 440s with no problems.

[Charlie @ Evergreen]

wow!! Thats amazing...for such a lil tuner box Are the RC's the way to go then on the link I found?? or is there another source of injectors everyone likes??

[Diverteh]

wow!! Thats amazing...for such a lil tuner box Are the RC's the way to go then on the link I found?? or is there another source of injectors everyone likes??

Aren't RC's just a re-badged Bosch?