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Hi ppls.

Well, we all know that you can throw on an S-AFC and tune the A/Fs and you can buy this to do that etc. but I wont to know the process to tune a car with a PowerFC.

Is it all about changing the timing, and then A/Fs and that's it, or is there more to it.

I figure theres a lot more to it, but what is it?

Perhaps some of our dignified tuners could de-mystify the whole process with a run down on what they do for 5 hours to our cars on the rollers.

I hope this makes a good thread.

BASS OUT

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Is it all about changing the timing, and then A/Fs and that's it, or is there more to it.

The only tuning i have ever done is mucking around with the old Microtech...i butchered the tune, but it ran no worse then the butchers who tuned it for the cars previous owner

But essentially you are right, you tweak injector duty cycle, and you play with ignition but depending on which ECU you are using you have to do it at different rpms, different loads/boost, different temps, different throttle positions etc etc. To do properly im amazed if they can do it in 5 hours.

The MT8 was never the greatest ECU but 4 years ago it was the norm for a lot of modified cars. I had the car re-tuned and it took them about 20 hours over a 3-4 periods for the car to drive like a std fuel injected car...no stalling, no pig rich idles when cold, no pinging but still good economy and good throttle response.

It is an art and the only tune that will take 5 hours is one they have done before and tweak for your individual car...so sure some mechanics steer you down a certain modification path, but for good reason as they can normally guarantee results and turn it around quicker.

From what I can work out : (DISCLAIMER - I DON'T KNOW SHITE)

First there is the intial wiring of the ECU / SAFC / Fuel Computer -whatever - If plug and play no need to worry

There is your initial setup: eg Injector Sizes, AFM sizes and Voltages (and MAP sizes etc on some ECUs)

Then there are things like idle, cold start, etc

Then there are 2 important maps you need to configure.

1) Fuel vs load vs revs

2) Timing vs load vs revs

These two maps form a sort of 3D graph of your setup. You change something in one axis - it may affect the other.

You need to monitor your A/F ratios, Your knock, (multiple ways/methods) whilst tuning.

You tune so your knock stays acceptable and the your A/F ratios (depending on load) are acceptable.

There is prolly much more to it than that -

I'm quite interested in this sort of thing -

The problem is that tuners who know what they are doing are not very willing to share info on a public forum.... (does them out of a job)

I plan to dip my toe in the water - by building a fuel computer for the Gloria and doing a road tune with a a wideband A/F meter.....

Anyawy - you need a bit of equipment and prolly a dyno and spend a lot of hours on it before one could call themselves a capable tuner.....

Hope that adds to the discussion - and maybe someone can elaborate and add to it :(

Cheers,

There are alot of reasons why people don't want to disclose information, be it because that's their income, to stay ahead of competition, because they have spent alot of time, money and training to get that information etc.

And then what if someone blows up their motor based on their input? More often than not it's a gimp who will try to discredit and slander the person who offered a suggestion in the first place. Can't really win can you?

yes and no.. I know many good tuners do read this forum and say nothing (SK goddom aside *slurp* :(), but then again unless you are there with the car, its all a bit of an armchair guess match..

while i am here, I remember reading this thread -> http://www.skylinesaustralia.com/forums/sh...ead.php?t=39620 had an excellent source of general bits and pieces.

I reckon i could count the number of mechanics in australia trained in Apexi PwerFC tuning on one hand. I'd say most of those guys apply their knowledge of manual tuning to electronic devices, which takes a fair bit of skill and gives them a leg up on the average joe.

Its not like in japan where you can pick up one of these

mag_6.jpg

And learn which ECU maps affect which part of you R32 or R33 GTR or GTSt. (Hence why I bought it and plan to translate it to help a few people understand what goes into tuning a Skyline Electronically).

And then what if someone blows up their motor based on their input? More often than not it's a gimp who will try to discredit and slander the person who offered a suggestion in the first place. Can't really win can you?

Damn you Doughboy, i leaned out the mixtures from 9.0:1 like you said, it made more power at 12:1 so i tried 16:1 to see how much more power i could make...then the whole thing glowed red then blew up...its all your fault :)

Getting it wrong is kinda terminal....but if you want to arm yourself with enough facts to be dangerous and annoy tuners with theoretical jibberish then enrol in this

What I would be interested to know is what do they teach at the seminar, how to tune, or the features of the MOTEC ecu. If it was the latter, then id assume itd be a waste of time for alot of us, but if it told us how to tune a car, that would be sweet.

I would think that seminar is about how to tune motec products and using there software/features/etc with only a little on EFI tuning in general.

Now for basic tuning.

For anyone that doesn't know yet you will need a wide band O2 sensor for this so dont try doing it with a stock o2 sensor with jaycar or autometer a/f gauge they are useless at anything other than idle :)

Fuel: fuel needs to be trimmed to effectively hold the correct a/f you wish to run at any given RPM/load point 12:1 ish on boost i think is about the normal safe tuning point with 14:1 being stock for idle/low load operation. The higher the a/f ratio the more on the edge it is so to speak.

Timing: Timing should be done on a dyno. Timing is increased until maximum torque say from idle to max torque. Then should be decreased little by little as boost and rpm increases. Some things i have read say about 1-2 degrees for every 1 psi but it all depends on the engine.

Also dont forget the economy side of things. Onroad datalogging can come in handy for this

tuning a ecu for max power is easy its getting the thing to drive like a stock car thats hard.

Hi-way and low load areas should receive at least the same attention that high load/boost does as it will make the car alot nicer to drive 99% of the time.

Pre-school tuning class over

B-mans disclaimer applies :rofl:

John

Hi ppls.

Well, we all know that you can throw on an S-AFC and tune the A/Fs and you can buy this to do that etc. but I wont to know the process to tune a car with a PowerFC.

Is it all about changing the timing, and then A/Fs and that's it, or is there more to it.

I figure theres a lot more to it, but what is it?

Perhaps some of our dignified tuners could de-mystify the whole process with a run down on what they do for 5 hours to our cars on the rollers.

I hope this makes a good thread.

BASS OUT

I can give you a copy of the english version of the pfc manual if ya want.

Its a rather large doucment and hours of reading :(

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