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Scott R's Avatar
 
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Quote:
Originally Posted by Duke Zink View Post
Scott, what's the timing graph look like? What's your max advance, idle setting, etc?
Timing is still via the original distributor, so I don't have a graph. I did however have the distributor rebuilt recently. Max advance is 33 right now, base timing is set at 5 deg. The idle setting is still done via the screw on the throttle body housing.

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2021 Model Y
2005 Cayenne Turbo
2012 Panamera 4S
1980 911 SC
1999 996 Cab
Old 10-06-2007, 05:33 PM
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Scott:
As I can't read anything on your AFR graphs, can you give an overview of where the AFR's were during the test? Were these AFR's read off your logging system, or was there an AFR probe in the tailpipe attached to the dyno?

That engine should make a boatload of power.

Pat
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Old 10-06-2007, 05:42 PM
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It's very difficult to figure out what your full throttle air/fuel ratio is vs rpm is from your pictures. Can you just summarize it for us in 500 rpm increments from 1000 to 6500 rpm? My guess it that you are running way too rich - I though I saw an AFR around 8.5:1, is that right? 42 lb. injectors is more than big enough for your motor, probably should be using something like 26 lb.
Old 10-06-2007, 05:45 PM
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First column is time, second is SecL, third is RPM fourth is MAP, sixth is lambda





479.747 124 30 79 0 1.529
479.809 124 31 79 0 1.549
479.873 124 30 79 0 1.549
479.936 124 31 79 0 1.588
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480.249 125 31 80 0 1.529
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481.933 126 33 79 0 1.49
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482.811 127 35 79 0 1.784
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482.933 127 34 79 0 1.686
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483.686 128 35 79 0 1.804
483.749 128 36 79 0 1.784
483.808 128 35 79 0 1.765
483.872 128 35 79 0 1.725
483.934 128 35 79 0 1.745
483.996 128 36 79 0 1.824
484.058 129 36 79 0 1.784
484.122 129 36 79 0 1.765
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484.308 129 37 79 0 1.784
484.372 129 37 79 0 1.824
484.435 129 36 79 0 1.804
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484.558 129 37 79 0 1.843
484.621 129 37 79 0 1.863
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484.747 129 37 79 0 1.804
484.809 129 36 79 0 1.804
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484.933 129 37 79 0 1.804
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485.436 130 38 79 0 1.667
485.499 130 39 78 0 1.588
485.558 130 38 78 0 1.667
485.622 130 40 79 0 1.745
485.685 130 39 79 0 1.765
485.748 130 38 79 0 1.686
485.811 130 38 78 0 1.686
485.871 130 39 78 0 1.725
485.933 130 39 78 0 1.804
485.997 130 39 78 0 1.725
486.059 131 39 78 0 1.784
486.123 131 38 78 0 1.804
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486.371 131 39 78 0 1.765
486.433 131 39 78 0 1.824
486.497 131 40 78 0 1.725
486.559 131 40 79 0 1.686
486.621 131 40 79 0 1.588
486.683 131 40 79 0 1.608
486.747 131 39 79 0 1.569
486.809 131 40 78 0 1.608
486.873 131 40 78 0 1.667
486.936 131 40 78 0 1.569
486.996 131 40 78 0 1.608
487.059 132 40 78 0 1.725
487.123 132 40 78 0 1.745
487.186 132 40 78 0 1.706
487.249 132 40 78 0 1.392
487.308 132 40 78 0 1.412
487.372 132 41 78 0 1.431
487.436 132 41 78 0 1.49
487.499 132 41 78 0 1.49
487.56 132 41 78 0 1.569
487.623 132 41 78 0 1.686
487.688 132 41 78 0 1.49
487.749 132 41 78 0 1.412
487.808 132 42 78 0 1.608
487.872 132 40 78 0 1.412
487.935 132 41 78 0 1.529
487.999 132 42 78 0 1.392
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488.497 133 42 78 0 1.686
488.559 133 43 78 0 1.627
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489.308 134 44 78 0 1.471
489.372 134 44 78 0 1.392
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489.498 134 43 78 0 1.49
489.561 134 44 78 0 1.471
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489.748 134 44 79 0 1.51
489.811 134 45 78 0 1.471
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492.059 137 50 78 0 0.549
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492.186 137 50 78 0 0.549
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492.872 137 50 78 0 0.569
492.934 137 48 78 0 0.569
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493.061 138 47 77 0 0.569
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493.371 138 50 78 0 0.549
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493.747 138 48 78 0 0.549
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493.936 138 51 77 0 0.549
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494.748 139 52 77 0 0.529
494.811 139 52 77 0 0.529
494.871 139 52 77 0 0.549
494.934 139 51 77 0 0.549
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495.061 139 51 77 0 0.549
495.121 140 52 77 0 0.549
495.183 140 52 77 0 0.549
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495.374 140 51 77 0 0.549
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495.621 140 54 77 0 0.549
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495.936 140 52 77 0 0.549
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496.058 140 54 77 0 0.549
496.122 141 54 77 0 0.549
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496.621 141 54 77 0 0.922
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496.811 141 52 77 0 1.314
496.874 141 54 77 0 1.235
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497.623 142 55 77 0 1.255
497.686 142 54 77 0 1.176
497.749 142 57 77 0 1.235
497.808 142 55 77 0 1.255
497.872 142 54 77 0 1.255
497.934 142 55 77 0 1.294
497.996 142 55 77 0 1.255
498.058 142 54 77 0 1.235
498.122 143 55 77 0 1.275
498.184 143 55 77 0 1.216
498.246 143 55 77 0 1.255
498.308 143 57 77 0 1.216
498.372 143 57 77 0 1.235
498.435 143 55 77 0 1.235
498.499 143 55 76 0 1.275
498.558 143 57 76 0 1.255
498.621 143 55 75 0 1.255
498.683 143 57 76 0 1.294
498.747 143 57 77 0 1.294
498.809 143 58 77 0 1.275
498.871 143 55 77 0 1.216
498.933 143 57 77 0 1.235
498.997 143 57 77 0 1.196
499.059 143 57 77 0 1.137
499.123 144 57 77 0 1.216
499.186 144 57 77 0 1.216
499.248 144 55 77 0 1.176
499.309 144 58 77 0 1.216
499.373 144 57 77 0 1.216
499.436 144 58 77 0 1.216
499.499 144 57 77 0 1.157
499.558 144 57 77 0 1.196
499.622 144 57 77 0 1.098
499.684 144 57 77 0 1.176
499.746 144 58 77 0 1.176
499.808 144 57 77 0 1.137
499.872 144 58 77 0 1.157
499.934 144 57 77 0 1.176
499.998 144 57 77 0 1.176
500.061 144 57 77 0 1.196
500.124 145 57 77 0 1.216
500.185 145 58 77 0 1.078
500.247 145 57 77 0 1.176
500.309 145 57 77 0 1.176
500.374 145 58 77 0 1.137
500.433 145 57 77 0 1.098
500.497 145 58 77 0 1.078
500.559 145 58 77 0 1.078
500.621 145 58 77 0 1.118
500.683 145 58 77 0 1.098
500.747 145 58 77 0 1.098
500.809 145 60 76 0 1.078
500.873 145 60 76 0 1.216
500.936 145 58 76 0 1.196
500.996 145 60 77 0 1.176
501.059 145 58 77 0 1.059
501.123 146 58 77 0 1.039
501.186 146 58 77 0 1.078
501.249 146 60 77 0 1.059
501.308 146 60 77 0 1.098
501.372 146 60 76 0 1.098
501.434 146 58 76 0 1.118
501.496 146 58 76 0 1.137
501.558 146 60 76 0 1.078
501.622 146 60 76 0 1.137
501.684 146 57 76 0 1.137
501.748 146 58 76 0 1.137
501.811 146 60 76 0 1.059
501.871 146 60 76 0 1.098
501.934 146 60 76 0 1.098
501.998 146 60 76 0 1.098
502.061 146 60 77 0 1.118
502.124 147 58 77 0 1.078
502.183 147 60 76 0 0.961
502.248 147 62 76 0 1.098
502.311 147 60 76 0 1.118
502.374 147 60 75 0 1.118
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2021 Model Y
2005 Cayenne Turbo
2012 Panamera 4S
1980 911 SC
1999 996 Cab
Old 10-06-2007, 06:06 PM
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This pull was AFTER we cut the VE bins by 40% in all the regions above 3000 RPM. Another thing t mention is that it only really idles rich, only ever has, this engine or the last. On top of that the MAP floats from bin to bin at idle and sometimes driving, it never parks on a number and just stays there.

EDIT: Forgot to add, any leaner and she bucks pretty bad in most bins, that and I have had a two year on-going accel issue where if you stomp on it it surges three times then takes off.
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Last edited by Scott R; 10-06-2007 at 06:11 PM..
Old 10-06-2007, 06:08 PM
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If that last column is really your mixture, then you need to start over. That lambda is all over the place, which equates to an AFR from 8:1(superrich) all the way to 22:1 (running on vapors). I'm surprised your LC-1 can even read that extreme. You should be targeting an Lambda of 0.88 at full throttle.
Old 10-06-2007, 06:31 PM
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Steve, what AFR does a .88 lamda equate to?

Cheers
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Old 10-06-2007, 06:35 PM
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Wideband O2 voltage
Lambda vs. AFR for various fuels

Vout Lambda Petrol LPG Methanol Diesel
1.40 0.686 10.08 10.63 4.39 9.94
1.45 0.696 10.23 10.79 4.45 10.09
1.50 0.706 10.38 10.94 4.52 10.24
1.55 0.716 10.53 11.10 4.58 10.39
1.60 0.727 10.69 11.27 4.65 10.54
1.65 0.739 10.86 11.45 4.73 10.71
1.70 0.750 11.03 11.63 4.80 10.88
1.75 0.762 11.20 11.81 4.88 11.05
1.80 0.774 11.38 12.00 4.95 11.23
1.85 0.787 11.57 12.20 5.04 11.41
1.90 0.800 11.76 12.40 5.12 11.60
1.95 0.814 11.96 12.61 5.21 11.80
2.00 0.828 12.17 12.83 5.30 12.00
2.05 0.842 12.38 13.05 5.39 12.21
2.10 0.857 12.60 13.29 5.49 12.43
2.15 0.873 12.83 13.53 5.59 12.66
2.20 0.889 13.07 13.78 5.69 12.89
2.25 0.905 13.31 14.03 5.79 13.13
2.30 0.923 13.57 14.31 5.91 13.39
2.35 0.941 13.84 14.59 6.03 13.65
2.40 0.960 14.11 14.88 6.14 13.92
2.45 0.980 14.40 15.18 6.27 14.20
2.50 1.000 14.70 15.50 6.40 14.50
2.55 1.037 15.25 16.08 6.64 15.04
2.60 1.078 15.84 16.70 6.90 15.62
2.65 1.121 16.48 17.38 7.17 16.26
2.70 1.169 17.18 18.11 7.48 16.95
2.75 1.220 17.93 18.91 7.81 17.69
2.80 1.276 18.76 19.78 8.17 18.50
2.85 1.337 19.66 20.73 8.56 19.39
2.90 1.405 20.66 21.78 8.99 20.38

. . .
4.00 free-air (can be used for calibration)
Old 10-06-2007, 06:37 PM
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Quote:
Originally Posted by Steve W View Post
If that last column is really your mixture, then you need to start over. That lambda is all over the place, which equates to an AFR from 8:1(superrich) all the way to 22:1 (running on vapors). I'm surprised your LC-1 can even read that extreme. You should be targeting an Lambda of 0.88 at full throttle.
I agree, but I can't hit that without that computer going screwey, the bucking, surging, unstable MAP. That coupled with the resets I get in the log has me wondering. If I can drop the bins 40% and see no change, then what the heck is going on? and why has it never idled?
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Old 10-06-2007, 06:41 PM
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Quote:
Originally Posted by Scott R View Post
EDIT: Forgot to add, any leaner and she bucks pretty bad in most bins, that and I have had a two year on-going accel issue where if you stomp on it it surges three times then takes off.
I don't know about MS at all.

Your accel issue sounds like it is rich. If it is lean it will backfire in the intake. Can you see any black smoke on accel?

I also think your injectors are big enough. I am running 55lb injectors in my car and I have more than twice your hp and mine are close to maxed out.
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Old 10-06-2007, 06:47 PM
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If you are using the stock 1980 dizzy then that is probably your problem. It doesn't have enough advance to do the job. You can use a 78-79 dizzy set to 7 degrees BTDC or so at idle or get your dizzy recurved.

-Andy
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Old 10-06-2007, 06:54 PM
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Quote:
Originally Posted by Eagledriver View Post
If you are using the stock 1980 dizzy then that is probably your problem. It doesn't have enough advance to do the job. You can use a 78-79 dizzy set to 7 degrees BTDC or so at idle or get your dizzy recurved.

-Andy
Ugh, kinda figured after everything that it may be ignition, I mean since nothing I have ever adjusted in the fuel arena, like accl enrichment, pulse width, or anything else for that matter has made a difference.

So, get a new distributor? Or get a new engine management system? Or switch back to CIS or carbs.... After a very expensive rebuild there is not a lot left in the kitty this year.
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Old 10-06-2007, 07:01 PM
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One more thing to add, what shows up as lean may actually be too rich. Overrich mixtures will foul plugs, causing misfires, which end up blowing O2 into the exhaust which the O2 sensor will read as a lean mixture. Anything over 1.2-1.3 lambda would be suspicious to me.
Old 10-06-2007, 07:14 PM
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Quote:
Originally Posted by Steve W View Post
One more thing to add, what shows up as lean may actually be too rich. Overrich mixtures will foul plugs, causing misfires, which end up blowing O2 into the exhaust which the O2 sensor will read as a lean mixture. Anything over 1.2-1.3 lambda would be suspicious to me.
Oh, I'm sure I have/had fouled plugs, I did after the rebuild. IN fact I have changed them three times now. What happens is that there is no flood clear on my setup, so if it floods, I have to disconnect the injector harness to clear it. I was waiting to replace the plugs again until I got to the bottom of this.
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Old 10-06-2007, 07:25 PM
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I would start with the basics. Run a compression check, and put the CIS system back on to check the integrity of the rebuild. Then dyno with the CIS on in order to get a baseline.

Steve is right, lambda should be close to 1.0 at almost all times. On modern cars, it's scary accurate all the time, even under accel...

-Wayne
Old 10-06-2007, 07:40 PM
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I have done quite a bit of tuning with a MS system. 42# injectors are WAY TOO BIG for your motor. I am using #30 pound injectors on a stock internal 3.0 and had to really drop the fuel pressure to get them to work. The car runs great at speed but my off-idle response is bad. I suspect I might be dribbling fuel just to keep a reasonable AFR at idle. I have some 21# to raise the fuel pressure to a reasonable level.

there is no way that you can control a short pulsewidth with an MS1 box and high-impedance injectors of that size.

I agree that your AFR run looks really rich. You are showing ~10:1 at 6K. that will just bog the system and give horrible throttle response.

Did you do any road tuning before going to the dyno? I have not spent any dyno time and my car runs so much better than it did with carbs. There is a very methodical method for tuning EFI. Its not that hard but can be time consuming if you don't follow the rules. first turn off all accel enrichments. When the engine is warm. tune the no-load sites with the car sitting in the driveway and using the idle screw to hit rpm bins. once you have a stable AFR in these regions start driving the car.

next you need to build an AFR table. you need to see where your MAP level is on level ground for the rpm bands. These will be your cruise sites and you can probably target around 14.5:1. maybe a little leaner. Then make your AFR table by smoothly blending the curve to 12.9:1 or so at any MAP reading above 70kPa. the low load sites (high vacuum - probably 30-50 kPa) can go a bit leaner maybe 15:1. Now drive the car and datalog. the first drives will be steady throttle at each rpm band in your AFR table. Try to hit them exactly. use different gears and the flattest terrain you can find. next move to a slight sloping hill and finally a steeper hill. then you can go to the WOT and high load sites.

I see you are already using MegalogViewer. If you have a good AFR table, use the VE analyzer. It works very well. keep driving, logging and analyzing. it will take 4 or 5 runs before you really start to feel a difference. If you take your time and really build a solid VE table you will have a fantastic running car. Then tune accel parameters to get rid of transition throttle stumbles.
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Last edited by jpnovak; 10-06-2007 at 08:06 PM..
Old 10-06-2007, 07:57 PM
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Scott,

you got me cursious and I fired up Megatune with a MS-1 configuration to take a look at the settings. When you say that fuel settings do not make a difference something is WRONG. You should see differences every time you make changes. Maybe you don't "BURN" the values to the controller. Or something is wrong with your injector settings and they are not controlled properly. Maybe they are really way to big and this is why you are having issues.

If I were you, I would start over: Save the current settings so that you have something to go back to in case and start with a clean sheet.

The first thing you need to do is to make sure the injector characteristics are set properly in the "Constant Value" tab. There is a pretty good writeup on the Megatune website. Follow it to the dot. Make sure the number of squirts is set correctly.

Next generate a generic VE table (Megatune can do this for you), disable all the acceleration enrichments and get the car warmed up and idling. You should see a change in the A/F ratio once you change the "Required Fuel" value. This the base fuel quantity for your engine. Everything else will hinge on this. If you change this value it is equivalent to adding or substracting a constant to the entire VE table. I set it so that the lowest bins are around 30 - 50.

When I change the "required fuel" value on the Type 4 I see a clear difference of A/F at idle. A change from 6.5mS to 7.0mS is visible on the wideband chanel. Every time you change something make sure you "BURN" the values to the controller. If not, they will be discarded once you power-cylce the MS-I.

Next, do data logging while driving around. This will be the best source for fine-tuning the fuel map.
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Old 10-06-2007, 11:26 PM
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I had a similar experience recently, that thread here: Engine Build Dyno Results

How does it drive, other than the idle issue?

I run 26# injectors on my 3.0 race car without a problem.
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Old 10-07-2007, 12:50 AM
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Scott,

one more thing: When I run the "Required Fuel" calculation with your injector size (42lb/h) for a 3000cc engine I get a suggested injector time of 7.6ms per cylinder while your msq file uses 11.6ms. Your setting is more than 50% higher This might explain why your data logs show rich conditions.

I still have my money on your engine running too rich and would try to verify this. Don't be concerned with peak HP for now. First get it to idle well and to drive well under medium load and cruising. The peak HP tuning on a dyno is last after you have dialed in your A/F's with lots of driving and data logging. Ask me how I know; I have had the Type 4 on a dyno way too early. What a waste of time. And I tried to cheat around proper tuning by using closed loop with the wide-band sensor (MS-II). Well, to cut a long story short, I didn't even ask the dyno guy to print out the runs, that's how sh|tty they were. I had to go back to the drawing board, disable the cloosed loop and do some old-fashioned data looging. And it made a world of a difference in driveabiltity.

Can you get a second independent LM-1 handheld O2 meter with a second wide-band O2-sensor into the tailpipe to verify your mixture? What are others running? (jpnovac, JohnJL) - maybe someone here can provide you his .msq file for reference. You'd have to change the required fuel# in the constants page or transform the VE table to account for the bigger injector size of yours compared to the one the .msq file was tuned for. There is a tool in the VE table menu to do that.

Out of curiosity: when you say
Quote:
Two years, and an engine later and it still won't idle without hunting!?!
what happened to engine #1?

Cheers,
Ingo
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Old 10-07-2007, 07:20 AM
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Quote:
Originally Posted by ischmitz View Post
Scott,

one more thing: When I run the "Required Fuel" calculation with your injector size (42lb/h) for a 3000cc engine I get a suggested injector time of 7.6ms per cylinder while your msq file uses 11.6ms. Your setting is more than 50% higher This might explain why your data logs show rich conditions.

I still have my money on your engine running too rich and would try to verify this. Don't be concerned with peak HP for now. First get it to idle well and to drive well under medium load and cruising. The peak HP tuning on a dyno is last after you have dialed in your A/F's with lots of driving and data logging. Ask me how I know; I have had the Type 4 on a dyno way too early. What a waste of time. And I tried to cheat around proper tuning by using closed loop with the wide-band sensor (MS-II). Well, to cut a long story short, I didn't even ask the dyno guy to print out the runs, that's how sh|tty they were. I had to go back to the drawing board, disable the cloosed loop and do some old-fashioned data looging. And it made a world of a difference in driveabiltity.

Can you get a second independent LM-1 handheld O2 meter with a second wide-band O2-sensor into the tailpipe to verify your mixture? What are others running? (jpnovac, JohnJL) - maybe someone here can provide you his .msq file for reference. You'd have to change the required fuel# in the constants page or transform the VE table to account for the bigger injector size of yours compared to the one the .msq file was tuned for. There is a tool in the VE table menu to do that.

Out of curiosity: when you say what happened to engine #1?

Cheers,
Ingo
Engine #1 was a 146K mile neglected motor with clogged cam spray bar on 4-5-6, couple that with 40% leak on two cylinders and it was time to go. The PO, or whoever, did a really poor top end rebuild to chase some broken headstuds. When I tore it down I found the right side chain ramp floating around inside the chain box, and that was just one of the many things done wrong. The guy obviously didn't have a copy of Wayne's book.

I'll go back to the drawing board today, but I still think as others have mentioned that there is something fundamentally wrong here, either in injector sizing, or something else. I really appreciate all of the time people are spending helping me out on this.

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Old 10-07-2007, 08:01 AM
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