Joe Perez

iTrader: (8)

This entire thread makes kitty sad.

Leafy

iTrader: (1)

Nope. power = (injector flowrate * duty cycle)/bsfc. I can do some substitutions and show you that torque and injector pulse width correlate but horse power is related to duty cycle. If I make the same power at two different points of the rpm band the duty cycle will be the same but the torque and injector pulse widths will be different.

nitrodann

That's literally exactly what I am saying.

Leafy

iTrader: (1)

I swear when I hit the quote button you were saying torque relates directly to injector pulse width.

Stephanie Turner

Keith needs a heat shield that fits, I completely agree. I have asked for him to mark his existing heat shield where it does not fit and send it to me so that we can make and/or alter one to fit. He refused saying he needed something on the car to drive it. I want the original heat shield (marked) to alter so that it takes the guessing out where to make it fit around. We offered to send a call tag and pay for the shipping, but we still do not have a heat shield to work off of to get him something that will work the second time (as opposed to the 4th or 5th time). We are more that happy to finish the heat shield for Keith, but we truly need the other back and marked where it does not fit.
Stephanie

18psi

iTrader: (76)

el

ohhhh

el

Stephanie Turner

My method of logging injectors does not allow me to see duty cycle on the injector. I can see the pressure and voltage, but not duty cycle. This is tuning the stock ECU and not a MSPNP. The sciences behind it are different and far less advanced than MSPNP. If the stock ECU does not log it, I am unable to log it unless it is done with an external device or source. But it is not rocket science to know when you run out of fuel. You get a lean spot that does not tune out (which we did not hit). You also get flat spots or dips in curves to indicate a problem - much like a TPSdot or MAPdot settings issue on a MSPNP. Which we did not also see. I am also able to log the knock sensor as well. Not that it does any good sometimes, but I can.

The fuel pump is almost tapped out as it does not hold steady fuel pressure. The fuel pressure on an NB should be rock solid and this car tends to waver a little from 61 to 58 psi. It was not displaying the classic "i'm about to fail" symptom of a lean spike at red line. Therefore I concluded that the fuel pump was old, but still working. It should be watched closely and changed within the year.

250 on stock injectors? 8 months ago I would not have said 230 whp was not possible on stock injectors unless you had a MSPNP and UNLESS I tuned the car myself or someone who knows more than me tuned it. If you have dyno sheets, witnesses, and photos to back it up - i'm game. Do I think 250whp can be done on stock injectors. I'm gonna say probably not. I do not think it is likely, but if anyone would like to prove me wrong have at it!

As for detonation - I guess I am bless that I am not deaf. I have quite good hearing and can easily discern valve noise, bearing noise, rod knock, suspension noise, exhaust leaks, etc. Personally, if you can't do any of the above you should not be tuning a car. I can hear detonation on the dyno in a Miata. The Miata is not a V8, Z car, Diesel, etc. When tuning those vehicles, yes, detonation cans are necessary. A Miata? Not so much. FWIW, this car has a 2.5" Enthuza Midpipe and Exhaust system. Detonation is VERY audible. And "silent" knock is also visible. Laugh and make fun of me all you want, but it is easily proven and will save your but if you know what to look for. A single puff of black smoke out the tail pipe or a gap in the steady stream of exhaust gas is an indication of detonation. A blip of the needle in the boost gauge can indicate where it might be occurring too. I will find the you tube video and post a link. A good dyno shop will have a big mirror or video available to the tuner to see such occurrences or provide someone to watch it.

Stephanie

Leafy

iTrader: (1)

um... you have rpm and the ecu must know how long its opening the injectors for (how the **** else would it do it? unless it was modeled to run on vacuum tubes and analog dreams), you can do this in excel.

Stephanie Turner

This Video link was originally posted by John from J&S knock sensors back in the day.

m.net thread where it was originally posted:
Question for all you tuning gurus out there - MX-5 Miata Forum

Stephanie Turner

Again, let me repeat, this is ECU is not advanced. This is the stock ECU we have modified. It is "dumb". The stock ECU does not read duty cycle. And it is not a MSPNP where it has the info at your fingertips. This ECU technology is "old school".
Stephanie

Joe Perez

iTrader: (8)

Will an OBD-II scanner operating in realtime monitor mode not show the [injector duration / injector duty cycle / fuel load / call it whatever name pleases you] on a Miata?

That would, to the best of my knowledge, make the Miata somewhat of a unique vehicle.

Leafy

iTrader: (1)

you can also back track it yourself from your tuning data. Surely you have a note pad file of the hex bin that has the fuel table on it.

Reverant

iTrader: (10)

No, it does not.

Stephanie Turner

Injector duration? No
Duty Cycle? No
Fuel load? Maybe. I will do a screen shot when I get back from picking up a Miata.
I use The DynoScan by Auterra for my OBDII logging tool.
Stephanie

Leafy

iTrader: (1)

Fuel load is normally ecu speak for maf value. Heck if you could even give us maf voltage or hz of this car under full song that would be interesting enough. Because besides the stock injectors not having enough head room there was always the concern in the back of my mind that you'd be close to saturating the maf at this power level.

Stephanie Turner

To an extent you may be talking over my head here - but this ECU is not set up in tables. It is all written in code and symbols. No "tables" to look at. If I knew anything about code, the hex bin might make sense to me. I tell Chip Torque what to change and they write the code. Again, make fun of me because I unable to write code, but when it comes right down to it, I don't need to know it - thought it could help sometimes.
Stephanie

Stephanie Turner

Running out of MAF and injector are two very different things. I can read MAF flow rate with my OBDII tool, and also MAF Voltage if done manually at the MAF. Running out of MAF voltage can be done without running out of injector. The stock MAF will stop reading at about 13-14 psi regardless of hardware, depending on the year. The injector has a few more variables.

You can add fuel one of three common ways:
1. Directly change fuel by lengthen the injector pulse width. Most common with Voodoo Box and Standalone ECUs
2. Indirectly change fuel by adjusting the MAF voltage the ECU sees. Most common with the Xede.
3. Manually raise fuel pressure via fuel pump or FPR.

This car was tuned with the ECU Reflash, which is a combination of 1 & 2.
Stephanie

18psi

iTrader: (76)

I now understand why the cars you tuned blew up afterwards. What happens when you're 1% away from the limit, have no idea where the limit is because you have absolutely no way of monitoring it, and the customer goes into lower elevation and denser air after getting "t00ned" like that?
"didn't look like it will fail immediately" so its good enough to hand off to a customer? ok got it.
it was a joke. sarcasm.

the fact that you're considering it seriously genuniely scares me.
You're a normal human being just like the rest of us. You're not special.
You've just come to accept a very very terrible and low standard for tuning, with which a car that does not:
1) immediately blow up
2) does not detonate like crazy that it breaks up or blows smoke
3) does not run out of fuel on the dyno
Is deemed OK to hand off to a customer that just paid you multiple thousands of dollars for the parts and tuning.

I am not a professional tuner by any stretch of the imagination, but I feel really bad for your customers, because any actual reputable tuner would cringe if told about your tuning practices.

All ecu's are written in code. In all tune-able ecu's this code is turned into tables.
Leafy is actually speaking in very simple tuning terms, like 2+2. the fact that this is over your head and you tune cars professionally, again, scares me.
The OEM ecu tables for the NA and NB are actually posted on this very site, I'd re-post them here but that'd be a waste of time anyway.
He's not talking about running out of MAF.

The oem ecu relies on a table to tell the injectors what to do at which load and which rpm. This requires a table. This table is different from the maf scale, which tells the ecu how much fuel is needed per how much flow the heated wire is recording. The two are closely related, but not the same thing.

I can post examples from other OEM ecu's if you wish.

*EDit: although it may be possible that the OEM mazda ecu is so ancient that it ONLY has the mass airflow scale and nothing else. That would be unlikely though since it would still need fuel targets.

Stephanie Turner

18psi, you obviously have a personal grudge and/or vendetta. You're prerogative. I wish you no ill will. And if you have first hand experience of my tuning, then please share. If it is second knowledge or an I heard, there are two sides to every story. But I will not debate those with you.

It is not my job to spend a customer's money. I give recommendations as to what should be done, it is up to them to do it and/or when to do it. And yes, I did tell Jerry that his fuel pump needed to be changed but it was not my opinion that it would immediately fail. Very few fuel pumps just up and fail without warning - especially on a car that is being monitored.

As for the engines that have failed under my tuning, I can only think of 1 that is truly my fault, beyond a doubt. A belt rubbed a catastrophic hole in a coolant line. I was driving, my fault. Other's have failed from problems I nor BEGI caused. Do you think every tuner out there learned in school? Probably not. We all learn by doing it and trial and error.
Stephanie

18psi

iTrader: (76)

Personal grudge? nah. I was mad when you lied to me repeatedly, but then Corky finally made it right and despite waiting for a very long time for parts I was promised within weeks, I was taken care of.

What I find disturbing is the obviously flawed methods you're using to tune people's cars. I'm pointing out things that bother me, because this is a discussion thread as far as I know, and not an advertising thread (which you are more than welcome to create since you even have a specific section of this forum to do it in). I wouldn't dare to even post questions in such thread, for fear of vendor abuse

I guess I'll stop picking apart your flawed info so you don't think I hate you?

BTW, here's an example of an OEM Miata table I was talking about


Notice its not a Megasquirt or Xede or any other screen shot. IIRC this is directly from Japan.