Is this too rich?
Thread Starter
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
Is this too rich?
Hi guys I have a question. During warm to hot engine temps, in open loop if I drive the car it will run at 11.0:1-11.5:1 Air/fuel ratio. Is this safe to drive on or is it too rich?
I have another tune that corrects this problem but brings up another problem that's even worse.
Thanks for any help.
I have another tune that corrects this problem but brings up another problem that's even worse.
Thanks for any help.
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
That's too rich for my liking.
Hot operation when lubrication needs to be at its best, running that rich washes the thin lube off the rings and cyl walls.
knowing that 14.7 is optimal, and that you DO gain a little more power with slightly richer ratios, ask yourself, is having that little bit of more power necessary to drive to work? or to the store? Because the truth is, its NOT.
IIWM,
I'd be saving the engine for times when that little bump in power would utilize it and NOT waste the engine life on everyday BS driving. A good tune should be able to get everything that engine has to offer without sacrificing the longevity of the engine. To run at more than (best guess) 12:1 is slow suicide for the motor.
JMO...
Hot operation when lubrication needs to be at its best, running that rich washes the thin lube off the rings and cyl walls.
knowing that 14.7 is optimal, and that you DO gain a little more power with slightly richer ratios, ask yourself, is having that little bit of more power necessary to drive to work? or to the store? Because the truth is, its NOT.
IIWM,
I'd be saving the engine for times when that little bump in power would utilize it and NOT waste the engine life on everyday BS driving. A good tune should be able to get everything that engine has to offer without sacrificing the longevity of the engine. To run at more than (best guess) 12:1 is slow suicide for the motor.
JMO...
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
Hi guys I have a question. During warm to hot engine temps, in open loop if I drive the car it will run at 11.0:1-11.5:1 Air/fuel ratio. Is this safe to drive on or is it too rich?
I have another tune that corrects this problem but brings up another problem that's even worse.
Thanks for any help.
I have another tune that corrects this problem but brings up another problem that's even worse.
Thanks for any help.
Last edited by WW7; Oct 18, 2014 at 05:46 PM.
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
On an 85, closed loop is on a timer. So it is common to start with a hot engine and drive in open loop.
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Thread Starter
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
Okay this might be a little complicated to follow, but this is how I came up with my tables.
I figured out that GM bases their tables off of 14.7:1
This is the AFR's that it comes out to.
9.59:1 -40*F - -18.4*F
10.8:1 -18.4*F - 3.2*F
11.03:1 3.2*F - 24.8*F
11.66:1 24.8*F - 46.4*F
11.89:1 46.4*F - 68*F
12.75:1 68*F - 89.6*F
13.8:1 89.6*F - 240.8*F
In the later models at 89.6*F - 240.8*F they changed the AFR from 13.8:1 to 13.25:1, so that's what I have targeted.
Judging on how mine were displayed with the values I had before the current table, I was able to figure out that mine has to be based on 22.5:1 AFR to achieve the target AFRs that GM has.
So, for example to get 13.25:1, the formula is:
22.5 - 13.25 = *9.25*
22.5 / 100 = *.225*
9.25 / .225 = 41.11% Change
So to confirm that formula, 22.5 / 100 = .225 x 41.11 = 9.25; 22.5 - 9.25 = 13.25
Now keep in mind, Tuner Pro changes whatever I type in to the closest number it has available.
So here are my CURRENT tables.
57.42
51.95
50.78
48.05
47.27
43.36
41.02
41.02
41.02
41.02
41.02
41.02
41.02
41.02
I figured out that GM bases their tables off of 14.7:1
This is the AFR's that it comes out to.
9.59:1 -40*F - -18.4*F
10.8:1 -18.4*F - 3.2*F
11.03:1 3.2*F - 24.8*F
11.66:1 24.8*F - 46.4*F
11.89:1 46.4*F - 68*F
12.75:1 68*F - 89.6*F
13.8:1 89.6*F - 240.8*F
In the later models at 89.6*F - 240.8*F they changed the AFR from 13.8:1 to 13.25:1, so that's what I have targeted.
Judging on how mine were displayed with the values I had before the current table, I was able to figure out that mine has to be based on 22.5:1 AFR to achieve the target AFRs that GM has.
So, for example to get 13.25:1, the formula is:
22.5 - 13.25 = *9.25*
22.5 / 100 = *.225*
9.25 / .225 = 41.11% Change
So to confirm that formula, 22.5 / 100 = .225 x 41.11 = 9.25; 22.5 - 9.25 = 13.25
Now keep in mind, Tuner Pro changes whatever I type in to the closest number it has available.
So here are my CURRENT tables.
57.42
51.95
50.78
48.05
47.27
43.36
41.02
41.02
41.02
41.02
41.02
41.02
41.02
41.02
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
Okay this might be a little complicated to follow, but this is how I came up with my tables.
I figured out that GM bases their tables off of 14.7:1
This is the AFR's that it comes out to.
9.59:1 -40*F - -18.4*F
10.8:1 -18.4*F - 3.2*F
11.03:1 3.2*F - 24.8*F
11.66:1 24.8*F - 46.4*F
11.89:1 46.4*F - 68*F
12.75:1 68*F - 89.6*F
13.8:1 89.6*F - 240.8*F
In the later models at 89.6*F - 240.8*F they changed the AFR from 13.8:1 to 13.25:1, so that's what I have targeted.
Judging on how mine were displayed with the values I had before the current table, I was able to figure out that mine has to be based on 22.5:1 AFR to achieve the target AFRs that GM has.
So, for example to get 13.25:1, the formula is:
22.5 - 13.25 = *9.25*
22.5 / 100 = *.225*
9.25 / .225 = 41.11% Change
So to confirm that formula, 22.5 / 100 = .225 x 41.11 = 9.25; 22.5 - 9.25 = 13.25
Now keep in mind, Tuner Pro changes whatever I type in to the closest number it has available.
So here are my CURRENT tables.
57.42
51.95
50.78
48.05
47.27
43.36
41.02
41.02
41.02
41.02
41.02
41.02
41.02
41.02
I figured out that GM bases their tables off of 14.7:1
This is the AFR's that it comes out to.
9.59:1 -40*F - -18.4*F
10.8:1 -18.4*F - 3.2*F
11.03:1 3.2*F - 24.8*F
11.66:1 24.8*F - 46.4*F
11.89:1 46.4*F - 68*F
12.75:1 68*F - 89.6*F
13.8:1 89.6*F - 240.8*F
In the later models at 89.6*F - 240.8*F they changed the AFR from 13.8:1 to 13.25:1, so that's what I have targeted.
Judging on how mine were displayed with the values I had before the current table, I was able to figure out that mine has to be based on 22.5:1 AFR to achieve the target AFRs that GM has.
So, for example to get 13.25:1, the formula is:
22.5 - 13.25 = *9.25*
22.5 / 100 = *.225*
9.25 / .225 = 41.11% Change
So to confirm that formula, 22.5 / 100 = .225 x 41.11 = 9.25; 22.5 - 9.25 = 13.25
Now keep in mind, Tuner Pro changes whatever I type in to the closest number it has available.
So here are my CURRENT tables.
57.42
51.95
50.78
48.05
47.27
43.36
41.02
41.02
41.02
41.02
41.02
41.02
41.02
41.02
21.1
12.9
11.3
7.0
5.5
-0.4
-7.8
-7.8
-7.8
-7.8
-7.8
-7.8
-7.8
-7.8
Thread Starter
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
Anyway, the AFR while hot with these numbers at idle was 19:1.
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
The numbers I posted are from a stock 85 tune. Enriching a little is fine, but 41% is insane.
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
I opened the stock BIN in Tuner Pro and got these numbers. The 5.86 is basically 6% as tequilaboy pointed out. If you run that lean with these numbers then something is very wrong.
34.77
26.56
25.00
20.70
19.14
13.28
5.86
5.86
5.86
5.86
5.86
5.86
5.86
5.86
34.77
26.56
25.00
20.70
19.14
13.28
5.86
5.86
5.86
5.86
5.86
5.86
5.86
5.86
Thread Starter
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
Have you tried starting with a stock tune? It would likely run lean. Your injectors are basically stock, so you should be able to adjust MAF tables, tweak timing and make some PE table adjustments. If you don't have a stock BIN I'll send you one.