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Discussion Starter #1
Are these more or less normal for a stock B235R at full load?

@ T = 17.293 s
MAF = 12.03 lbs/minute
RPM = 2847
Air-mass/combustion = 958 milligrams/combustion

@ T = 19.426 s
MAF = 14.84 lbs/minute
RPM = 3204
Air-mass/combustion = 1050 milligrams/combustion

@ T = 21.589 s
MAF = 16.27 lbs/minute
RPM = 3566
Air-mass/combustion = 1,035 milligrams/combustion

@ T = 23.682 s
MAF = 17.01 lbs/minute
RPM = 3916
Air-mass/combustion = 985 milligrams/combustion

Just doing some fault tracing, also curious what a "norma" ignition curve looks like for the B235R. Here's mine:



Any information is appreciated!

Adrian~
 

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Hej !

About ignition timing, first of all, we have an "absolute ignition map". And then several compensation maps and factors. So, it's kind of difficult to say what's "normal".
About the mg/c, I really should go to bed now.
I'll check my logs tomorrow, maybe.
 

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Dr Boost what would we do without you? :)

Sorry Adrian but I didnt even understand the question :roll:
 

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Discussion Starter #4
Hmmm, the question was a little vague.

It's a difficult question to be specific about. The best way to ask is if the values are "normal" ... but only people with data-loging capability, or direct programming insight into T7 would be able to say for sure. :oops:

The other question is, "How much is the car being limited by octane."

I tried to answer the first question on my own by re-setting the ECU and seeing what the "initial" values were upon re-set.

Here's what the values were upon re-set.

mg/c = ~ 1,150 -average and consistent

Timing:

3,000 RPM = ~2-10 BTDC

5,000 RPM = ~5-14 BTDC



That's a little better than my previous values, even though the conditions were very similar. More data can be found in the Viggen Road Test Data thread: http://www.saabcentral.com/forums/viewtopic.php?t=40594&postdays=0&postorder=asc&start=0
(posted in 9-5 forum as it's engine specific, and there are a lot more B235R's in 9-5's than 9-3's)

The second question I will answer later this week with some unleaded high octane race fuel.

Get some sleep Dr. Boost. I didn't mean to come across as bothersome. :-? :oops:

Adrian~
 

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Discussion Starter #5
I think the fault lies in ECU adaption.

In these two logs the car was driven hard, but intake temps, coolant temps, and ambient temps were the same. In both cases the car was driven out to redline at least once:

Before ECU re-set:
http://img.photobucket.com/albums/v14/SaabTuner/Full_MAF_Log_Before_Reset.jpg

After ECU re-set:
http://img.photobucket.com/albums/v14/SaabTuner/Full_MAF_Log.jpg


The difference between those two ECU settings is roughly 55 hp worth of airflow. That's a significant difference.

Adrian~
 

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Adrian W said:
I think the fault lies in ECU adaption.

In these two logs the car was driven hard, but intake temps, coolant temps, and ambient temps were the same. In both cases the car was driven out to redline at least once:

Before ECU re-set:
http://img.photobucket.com/albums/v14/SaabTuner/Full_MAF_Log_Before_Reset.jpg

After ECU re-set:
http://img.photobucket.com/albums/v14/SaabTuner/Full_MAF_Log.jpg


The difference between those two ECU settings is roughly 55 hp worth of airflow. That's a significant difference.

Adrian~
Adrian please
convert all your logs into mg/combustion, its a lot more easier to compare the results. Just looking at the plain MAF value wont do you much good as you know, since xxx g/s @ 3000rpm is a whole different story than the same xxx g/s @4000rpm

Here is an old log from my car

RPM [mg/combustion]
2618 1364
2863 1300
3140 1309
3417 1282
3693 1349
3949 1292
4202 1228
4431 1192
4639 1164
4811 1135
4972 1110
5145 1114
5304 1052
5455 1012
 

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Discussion Starter #7
MAF / RPM / mg/c

13.32 / 2781 = 1086
14.53 / 2973 = 1108
15.96 / 3157 = 1140
16.88 / 3345 = 1145
17.61 / 3534 = 1130
18.77 / 3725 = 1143
20.34 / 3917 = 1178
20.21 / 4101 = 1118

I'm getting even MORE frustrated. I just put in a tank of 100 octane unleaded race fuel and my results have not improved at all. In fact they have gone down.

Fault Tracing:

1. The problem is definitely heat-related. The harder you drive it, the less power you have, irrespective of octane rating.

2. The problem is NOT octane related. No change in any data despite running 100 octane unleaded race fuel.

3. The coolant and intake temps are below normal due to an 82C degree thermostat and insulated piping.

4. Oil temperature suspect, but unknown. Stuck oil thermostat?

5. Annoying buzz from the interior temperature sensor. (Very annoying indeed.)

6. ECU re-set seemed to have no affect on data this time, but perhaps I didn't disconnect it long enough?

7. Car reaches "target" boost values ... so the boost system isn't faulty. The ECU just doesn't want to run full boost.

8. No Diagnostic Trouble Codes.

What is left to check? Since octane doesn't seem to affect power output, perhaps there is something wrong with one of the ECU's sensors?

So frustrating!

Adrian~
 

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Adrian W said:
MAF / RPM / mg/c

13.32 / 2781 = 1086
14.53 / 2973 = 1108
15.96 / 3157 = 1140
16.88 / 3345 = 1145
17.61 / 3534 = 1130
18.77 / 3725 = 1143
20.34 / 3917 = 1178
20.21 / 4101 = 1118

I'm getting even MORE frustrated. I just put in a tank of 100 octane unleaded race fuel and my results have not improved at all. In fact they have gone down.

Fault Tracing:

1. The problem is definitely heat-related. The harder you drive it, the less power you have, irrespective of octane rating.

2. The problem is NOT octane related. No change in any data despite running 100 octane unleaded race fuel.

3. The coolant and intake temps are below normal due to an 82C degree thermostat and insulated piping.

4. Oil temperature suspect, but unknown. Stuck oil thermostat?

5. Annoying buzz from the interior temperature sensor. (Very annoying indeed.)

6. ECU re-set seemed to have no affect on data this time, but perhaps I didn't disconnect it long enough?

7. Car reaches "target" boost values ... so the boost system isn't faulty. The ECU just doesn't want to run full boost.

8. No Diagnostic Trouble Codes.

What is left to check? Since octane doesn't seem to affect power output, perhaps there is something wrong with one of the ECU's sensors?

So frustrating!

Adrian~
Adrian, do you know how much airmass you're supposed to get.
The valus I posted above are run with an upgrade ECU.
 

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Discussion Starter #9
Adrian, do you know how much airmass you're supposed to get.
The valus I posted above are run with an upgrade ECU.
:lol: No I don't. That's why I started this thread!

Last night after running around with 100 octane race fuel, the problem persisted. The car just would not run "full boost" despite coolant and intake air temps being below stock values. (Should have been less knock sensitive, not more!)

I reset the ECU and the problem persisted. It just refuses to run full power. And the power drops for long periods after just a few seconds on boost.

It acts like it is being heat-soaked, but the coolant and intake air temperatures are not high. Only the oil temperature is unknown.

Adrian~
 

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Discussion Starter #10
MG/C with 100 octane race fuel: :cry:

Time RPM

39:734 2250
40:218 2431
40:703 2607
41:187 2828
41:671 3006
42:156 3217
42:625 3428
43:109 3607

Regression of RPM: RPM = 407.15T - 13,944.7

Time / Calculated RPM / Flow - mg/c

39:968 / 2328 / 10.09 - 983
40:437 / 2519 / 11.43 - 1029
40:921 / 2716 / 12.20 - 1019
41:421 / 2919 / 13.48 - 1047
41:890 / 3111 / 13.90 - 1013
42:359 / 3302 / 15.27 - 1048
42:859 / 3505 / 14.01 - 906.6
43:328 / 3996 / 15.09 - 856.5


Why on earth does it keep adapting down even with 100 AKI octane race fuel? It makes no sense! On another data-log that same night I was getting 1122 mg/c even at 4500 RPM.

Maybe the T7 ECU is programmed with the stock EGT in mind, and won't let you boost hard unless you've driven softly for a long enough period to cool things down? Even that wouldn't explain some of its odd behavior. It makes no sense.

Adrian~
 
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