Random Thoughts - Part Deux [NO POLITICS]

[spike021]

Got rejected from the place I wasted five hours interviewing at last week. Then today I had scheduled meeting with my boss and he flaked on me after forty minutes of me waiting and not hearing back from him if something had come up. Wooooo /s

Kinda ridiculous.

[Spuds]

Originally Posted by Ultramaroon

I will. I'm not afraid of looking dumb here.




Oh! Maybe that's what I'm missing. I thought I am supposed to get all the CL data and then go to OL.


I'll read some more tonight. I'm pretty excited about tweaking the stock ROM a little at a time instead of just blasting the engine with some mystery OTS tune.


MAF scale is just a tiny first step. Sapphireho's airbox gave me the push I needed.

Yeah, read about the cl-ol transition. It will transition to OL when a certain load or rpm or (some other I'm forgetting about) condition is met. Key word is "or". There is also a delay built in for each condition so that obfuscates the transition point. I've set my delays to 0, but that might make it more difficult to set a scale because of how quickly it transitions.

Just wait till you get a temperature swing and it throws everything off. I get swings of 6% between summer and winter.

[Tcoat]

Originally Posted by ichitaka05

One of automotive mod debate should never be talk bout... Pulley, cuz no matter what, it'll get ugly.

Oh can I go reply to his reply latest statement? Please. Please!

[Spuds]

Originally Posted by Tcoat

Oh can I go reply to his reply latest statement? Please. Please!

Todas site specifically states the benefit is underdriving components and less inertia, but nothing about vibration. My redacted post said as much, gave an experimental procedure to prove the point and then reiterated my offer to do the math.

[Ultramaroon]

Originally Posted by Teseo

That statement triggered me in so many levels

Glad it's not just me. I get so much "Pshhh, whatevs!" whenever I express concern about OTS tunes that I quit talking about it.


I don't want to turn it over to anyone because I'm not looking for maximum anything. I just want to get it to run as sweetly as possible on 92 octane and understand exactly how I changed the stock tune to get there.

[Tcoat]

Originally Posted by Spuds

Todas site specifically states the benefit is underdriving components and less inertia, but nothing about vibration. My redacted post said as much, gave an experimental procedure to prove the point and then reiterated my offer to do the math.

Not to mention that isn't the ONLY thing they do to the engines. It is one small spec of the overall picture and not the reason people win races. Bolt on one part and you have yourself a race car! If it was only that simple.

[ichitaka05]

Originally Posted by Tcoat

Oh can I go reply to his reply latest statement? Please. Please!

Hahaha I read it. We only wait and see if he does make a new thread bout pulley or not. From there, I'm not doing anything about it in that thread. Cuz I'm not going to read one word in that thread.

On topic of this random thought, I'm kinda tempted to leave work early to get emission and registration done for my car (due this month)... or just procrastinate til 25th (which I've taken off) to do it.

[Spuds]

Originally Posted by ichitaka05

Hahaha I read it. We only wait and see if he does make a new thread bout pulley or not. From there, I'm not doing anything about it in that thread. Cuz I'm not going to read one word in that thread.

On topic of this random thought, I'm kinda tempted to leave work early to get emission and registration done for my car (due this month)... or just procrastinate til 25th (which I've taken off) to do it.

Why do today what can be done tomorrow?

[Ultramaroon]

Originally Posted by ichitaka05

Hahaha I read it. We only wait and see if he does make a new thread bout pulley or not. From there, I'm not doing anything about it in that thread. Cuz I'm not going to read one word in that thread.

On topic of this random thought, I'm kinda tempted to leave work early to get emission and registration done for my car (due this month)... or just procrastinate til 25th (which I've taken off) to do it.

Originally Posted by Spuds

Why do today what can be done tomorrow?

Yeah, blow it off as long as possible.

[Azzudien]

Originally Posted by ichitaka05

Hahaha I read it. We only wait and see if he does make a new thread bout pulley or not. From there, I'm not doing anything about it in that thread. Cuz I'm not going to read one word in that thread.

On topic of this random thought, I'm kinda tempted to leave work early to get emission and registration done for my car (due this month)... or just procrastinate til 25th (which I've taken off) to do it.

Live in NY, I routinely blow off the inspection on my cars for about 2 months after they expire. If you are only 1 or 2 months over cops just give you a warning. Insurance company hasn't caught on yet, and you actually get 14 months out of an inspection.

[Nevermore]

Originally Posted by Tcoat

Not to mention that isn't the ONLY thing they do to the engines. It is one small spec of the overall picture and not the reason people win races. Bolt on one part and you have yourself a race car! If it was only that simple.

So what you're saying is... If I do a full exhaust and tune, but ALSO add pulleys and a driveshaft, then I'll be driving a rocket ship?

[Tor]

Originally Posted by Ultramaroon

I'm teaching myself how to scale the MAF according to @steve99's instructions. The procedure requires capturing lots of steady-running, closed-loop data. The problem is -- and I can't imagine it's easy for anyone -- that, in order to get data at the upper end, the engine must be operated at both high RPM and close to WOT for extended runs.

Who the hell can do that? And where? I would need to drive all the way down to the California border to take data speeding like an idiot up Grants Pass.

The ECU is only in CL up to 4200 rpm, so you don't have to (you can't) make CL runs to red line. You don't need run at WOT for extended time either.

You just need 3 logs:

1) 3-4x WOT pulls from 2000 to redline in 3rd gear.
2) A log with 10x CL pull (<30% accellerator) from 1600 to 4500 rpm. Do them in different gears (2nd or 3rd), with different inclination (hills help but it's not a necessity) and different pedal pressure to reach into as many manifold pressures as possible.
3) A 20 min log with normal driving in different gears and speeds and without being too aggressive on the throttle.

All logs needs to be done at the same temp. Don't make long frequent stops. It's the intake temp that needs to be the same. Best is around 69 deg F (20 c) as this is what the compensation tables are zeroed around.

Thats all the easy part.

Next is filtering the data to sort out crap. You want to use KN47's formulas to calculate an error % and change (delta) in MAF voltage over time (dV/dt).

Sort on dV/dt less than 0.5 (excludes tip in errors) and error % less than 18 (excludes overrun). Sort on CL first, then OL. Use the log stats tab of vgi's tool, as it gives you much more control.

Now you have a "raw" corrected MAF. The next challenge if filtering out things that are off and should be corrected else where, like wierd bumps in the curve.

I use KN47's adaptation of 86inches tool which makes a logarithmical smoothing. Still it requires manual inputs and takes some practice to use.

When all this is done, you proceed to step 2. Make the same kind of logs again, and this time apply the error correction to the "Engine Load Compensation" table. I will sort correct the bumps you sorted away in the MAF scaling.

The thing is:
You can hit the same MAF at e.g. 3600 rpm 0.5 MAP (manifold pressure) or e.g. 2400 rpm and 0.7 MAP... just as an example.
The flow in the intake manifold may be different, so you will have different error % in the two areas for the same MAF value. So the same MAF value won't fit in both cases. Hence the ELC table to compensate for that.

In short: You want to keep the MAF scale smooth and adjust bumps in ELC (kind of average them in MAF first so the ELC corrections can be kept as small as possible). You may want to go back and forth adjust MAF then ELC then MAF etc. Depending on how much practice you have sorting out which correction belongs where.

This is just a fraction of all the steps that are involved in my process. To be honest I don't think more details will help. Because there is still an amout of "feel" you need to develop that you only get from practice.

So the things you need to ask your self:
- How good do I want my result to be?
- How much time am I willing to spend doing it?
- Would I be better off paying someone to do it?

I'm not trying to discourage you in any way. But this is a steep learning curve and in my opinion a waste of time to learn to tune ONE car (unless you really like it as a hobby).

Originally Posted by Ultramaroon

How far up the MAF curve have you gotten in CL? Maybe I'm doing it wrong.

It will run in CL up to approx 3 volts. There is an overlap and OL starts from around 2.5 volt and up to a max of approx 4.2 volt on a NA engine. The OL data from 2.5 to 3 volts should not be accounted for in the MAF scaling as the CL portion is more important not to mess up your LTFT.

Originally Posted by Ultramaroon

All I ever see with dynos are WOT pulls. Can they be used as dummy loads for long runs?

Yes, the above method is basically the same that could be achived if using a "load-bearing dyno" (using an Eddy-current brake). Most older dynos are "inertia dynos" though and are basically only useful to tune WOT.

Originally Posted by Teseo

Ask @Tor. He knows about tactrix too and develop his tune from scratch

I didn't start from scratch. I started with OFT/Wayno tune and went from there. But I changed so much that I at some point considered to start over with a stock A01G. I never bothered as in the end I was able to get everything to line up pretty well.

Also "scratch" is a stretch in any case as almost any tune is basically a light modification compared to the complexity of the stock ECU logic.

[Sapphireho]

Originally Posted by Tor

The ECU is only in CL up to 4200 rpm, so you don't have to (you can't) make CL runs to red line. You don't need run at WOT for extended time either.

You just need 3 logs:......

OMG, Ultra is going to pleasure himself reading this.

[cjd]

Originally Posted by Sapphireho

I'm sure they can, but what do I know.

I do know that there are a lot of guys that claim to be tuners that load an off the shelf tune (like from Delicious), put the car in the dyno, do a couple WOT pulls to adjust a couple things for max HP and charge $500.

When I had my car done by a real master tuner he had it on the dyno for like 6 hours. I'm sure he did more than WOT pulls. The car runs perfect in all situations, whether I'm carving the hills, sitting in traffic, or trying to find a parking spot.

I've done more than WOT pulls, though that's most/all of them now. Need to get the car out more, last tank of gas sucked timing I guess... Not my usual preference. Will be curious if my preference has real performance behind it. Also, third gear pulls to redline are kinda sketchy to be doing in the city... On ramps work, but I have to abort half the time.