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Old 06-02-2010, 04:42 PM   #1
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Question Bizzare dyno/tuning results? Tell me what the **** is going on?!

Ok, just spend 4hrs at the dyno with not-my-car.

Subject:
- EU-model MX-5 94
- stock 1.8 engine
- 125.000mi of which 12 boosted.
- 4spd, 4.1 diff

Previous configuration:
- Old and tired T25 turbo
- 0.85 bar (12-13psi)
- 5th injector and 7* base timing.
- AFR near 12.
- Output: 216rwhp

Current setup:
- Brand new 2860 .86A/R
- 0.80 bar (11-12psi)
- Output: 225rwhp
- MS2
- AFR near 12
- Output: 225rwhp

The basemap was pretty retarded (in both ways) so it took quite some time to get any power out of the engine. First run with how we got the car gave 200rwhp and we massively increased timing and stopped at 225rwhp.

The weird thing is that we're now running up to 30* timing in the upper load and rpm ranged with no knock. This is a bizzare amount?!

Attached all data I could grab together.

Questions:
- Is it reasonable to expect more than 220rwhp on an 2860 at 11-12psi?
- What is up with running up to 30* of timing without knock?
- Look at the timing jump we made and how little effect it had (10* jump, 25 rwhp)

Clogged air filter?
Misfiring due to weak coils?
Attached Thumbnails
Bizzare dyno/tuning results? Tell me what the **** is going on?!-ringmazda20100602-dynorunmlv.png   Bizzare dyno/tuning results? Tell me what the **** is going on?!-ringmazda20100602-dynorun.jpg   Bizzare dyno/tuning results? Tell me what the **** is going on?!-ringmazda20100602-ignmapbase.png   Bizzare dyno/tuning results? Tell me what the **** is going on?!-ringmazda20100602-ignmapbizzare.png   Bizzare dyno/tuning results? Tell me what the **** is going on?!-ringmazda20100602-vetable.png  

Attached Files
File Type: msq 2010-06-02_17.05.23.msq (50.1 KB, 65 views)
File Type: msl 2010-06-02_17.05.19.msl (777.9 KB, 50 views)
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Old 06-02-2010, 04:59 PM   #2
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it WILL knock and blow out ring lands once on the street. fwiw, I give it 2 miles.


you probably need to adjust the timing latency. At what put did adding timing not give you power? I'd go back to that point and retard it a few degrees.
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Old 06-02-2010, 05:11 PM   #3
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suicide spark table fail.
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Old 06-02-2010, 05:13 PM   #4
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Quote:
Originally Posted by Braineack View Post
you probably need to adjust the timing latency. At what put did adding timing not give you power? I'd go back to that point and retard it a few degrees.
You can skip you BS prophecy and help a brother out with what's wrong with the MS2 MSQ.

Adding timing keeps giving more power (3* = 3 rwhp or so) but we decided to call it a day and figure this bitch out.
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Old 06-02-2010, 05:15 PM   #5
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Quote:
Originally Posted by hustler View Post
fail
the fail is in the MS2 that some clueless installed
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Old 06-02-2010, 05:24 PM   #6
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Is the timing even in sync? Don't blame the MS-II.

MS-II is 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 99999999999999999999999999999999999999999999999999 999999999999999999999999999999999999999999 times better than MS-I.


EDIT: I looked at the MSQ, this is on a 36-1 toothed wheel? The trigger angle offset of 0 suggest the timing wasn't synced when installed.

What coils is it running? the dwell and battery dwell correction curve doesn't seem setup correctly.


needs more idle control. hell even simply tuning the AFRs at idle will help that bitch idle smooth.
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Old 06-02-2010, 05:26 PM   #7
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knock resistance increases with RPM?
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Old 06-02-2010, 05:33 PM   #8
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Quote:
Originally Posted by y8s View Post
knock resistance increases with RPM?

Ask Neo how his 7.6:1 CR pistons look...
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Old 06-02-2010, 05:44 PM   #9
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Quote:
Originally Posted by Braineack View Post
Is the timing even in sync? Don't blame the
EDIT: I looked at the MSQ, this is on a 36-1 toothed wheel? The trigger angle offset of 0 suggest the timing wasn't synced when installed.
Yes it's on a 36-1. I was curious too. How do I tell MS2 to fix the timing at 10BTDC and then adjust? Need to find the MS1 equiv settings.

However we checked at 0* and in vacume at 35* and that matched with a timing light...

Quote:
What coils is it running? the dwell and battery dwell correction curve doesn't seem setup correctly.
OEM Mazda 1.8 coil pack. Please post your values/table/map?

Quote:
needs more idle control. hell even simply tuning the AFRs at idle will help that bitch idle smooth.
I know. Idle valve was pluggen by someone so needs fixing.
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Old 06-02-2010, 05:44 PM   #10
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Never mind.
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Old 06-02-2010, 05:57 PM   #11
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Let me guess, Dynojet?
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Old 06-02-2010, 06:03 PM   #12
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Quote:
Originally Posted by Full_Tilt_Boogie View Post
Let me guess, Dynojet?


http://www.superflow.com/Dynamometer...dyn30_awd.html
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Old 06-02-2010, 06:04 PM   #13
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Actually, I think DynoJets are banned in the EU
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Old 06-02-2010, 06:28 PM   #14
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Sounds like your base timing is wrong in MS
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Old 06-02-2010, 06:34 PM   #15
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Quote:
Originally Posted by Spookyfish View Post
Yes it's on a 36-1. I was curious too. How do I tell MS2 to fix the timing at 10BTDC and then adjust? Need to find the MS1 equiv settings.
under more ignition options, something like that, there is a drop down selection for: use table or fixed value. once you select fixed value, you can enter in the number you wish to lock it at.

actually the dwell might be okay...it's running 3.0ms cant remember what the typical number is.
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Old 06-03-2010, 06:45 AM   #16
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Quote:
Originally Posted by Braineack View Post
under more ignition options, something like that, there is a drop down selection for: use table or fixed value. once you select fixed value, you can enter in the number you wish to lock it at.
Found it. That actually checked OK at 0 and 33 in vacume.
Quote:
actually the dwell might be okay...it's running 3.0ms cant remember what the typical number is.
DIY basemap is 3.1. Should be ok...
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Old 06-03-2010, 03:53 PM   #17
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What is "use prediction" under IGN settings and should I turn it off?
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Old 06-03-2010, 04:07 PM   #18
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Quote:
Use Predictor is a scheme used to anticipate the amount of time before the next TDC event.
First, the line of code that uses the prediction is:

dtpred += (inpram.Dtpred_Gain * (long)(dt3 - dtpred_old) / 100);

The Dtpred_gain value is the gain percentage read in (input in MegaTune above). The dt3 variable is the just-computed time delta. The drpred_old is the last delta time value.

In our case here we control ignition, which then causes the crank acceleration. So we predict the point to fire, and when the spark occurs the crank gets the "kick" to accelerate.

So ... if we have two tach points it is possible to predict into the future with simple "last interval" derivative (compared to higher derivatives) since the change in crank angular velocity is caused by our ignition event. After the explosion the crank accelerates, but hopefully we get another tach input in order to build up a new time derivative to predict where to place the next spark event.

All of this excludes changes in crank angular velocity due to compression, load variations, moments of inertia, etc. And the ignition event and subsequent expanding gases are not an infinite, short step function impulse on the crank (look up mass fraction burned and Weibe function in Heywood).

But this does illustrate the "causality" of the whole crank position problem - you do not know exactly where the crank is positioned until you get the next position pulse event. At least to the positional error of the tach circuitry. After this point the position is just a prediction w/ associated prop error until the next pulse comes in...

There is a "hidden" variable () within the code that simply subtracts the last prediction from the current tach pulse update. In other words the code uses a derivative to compute when the next tach pulse comes in, then later on the actual tach pulse comes in. The error in this is simply the subtraction. See the line of code:

outpc.spare[0] = (int)((outpc.rpm * (dt3 - dtpred_old)) / 16667); // degx10
What this is doing is taking the current delta_t based on the latest tach update and subtract the previous delta_t value (dtpred_old). This value is multiplied by the current RPM and divided by 16667 in order to get the variable into degrees crank * 10. So the result is in crankshaft degrees, and shows the error in the last prediction compared to the current updated prediction.

The result is placed into the spare output runtime variable. Now this variable is not defined in the .ini file so it would have to be placed there. It appears after the egoV2 variable, see the runtime variable list in the code and correlate with the ini file. Be sure to note that it is x10 units. Useful is putting this in the gauge list and the datalog.

Now - some warning on this, since this variable can be easily misinterpreted without thinking what it represents. First, note that it will always be in error whenever there is an acceleration event. The MS code does not have a psychic code mod built into it (yet) so the acceleration event has to be sensed via the tach input stream. So there will be places where the last delta_t does not correlate with the new delta_t with acceleration/decel, and there will be corresponding error. This is why it is a good idea to place your ignition events somewhere close to a point where the latest update occurred.
I've always had it off.
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Old 06-03-2010, 04:09 PM   #19
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Quote:
Originally Posted by Braineack View Post
Use Predictor is a scheme used to anticipate the amount of time before the next baby event.
There, fixed it for you.
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Old 06-04-2010, 12:43 AM   #20
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So use_predictor simply assumes a constant acceleration based on the last 3 tach events?
And if use_predictor is off it assumes constant angular velocity based on the last 2 tach events?
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