Tuning help can go past 15 psi.

[yukondoit]

Alright went to the track to tune my car in and get some logs legally and the best time i managed was a 15.6 at 94 mph. Im a/t some my 60 ft are horrible till i get a high stall converter but my question is why i start knocking after `15 psi. my mods are in my profile. i still need an exhuast and charge pipes could this be why?

Sorry the log is so long, there is two runs there.

Engine RPM Ignition timing advance Air temperature
856 16 136
852 16 136
852 16 136
852 15 136
856 16 136
848 16 136
856 16 136
856 16 136
844 16 136
856 16 136
844 17 136
1388 18 136
2256 20 136
2600 20 131
3324 13 125
4376 12 116
5680 16 109
6700 0 105
4692 13 105
5188 13 104
5636 14 104
5988 16 102
6284 17 100
6640 -2 100
4716 12 100
4824 13 100
5000 13 98
5188 13 98
5352 14 98
5532 14 96
5652 35 100
5348 35 104
5172 34 107
4972 34 109
4768 34 109
4576 34 109
4428 34 111
4244 23 111
3192 23 111
2172 17 111
1468 19 111
1260 15 111
1208 14 111
1184 14 111
1148 13 111
1112 12 111
1128 12 111
1080 12 111
1068 11 111
1096 12 111
1084 12 111
1072 11 111
1080 12 111
1084 11 111
1088 12 111
1076 12 111
1092 12 111
1056 10 111
1120 13 111
1172 14 111
1244 15 111
1228 14 111
1212 15 111
1160 12 111
1064 11 111
1064 11 111
1064 11 111
1068 11 111
1044 10 111
1032 10 111
1056 11 111
808 16 123
804 14 123
816 15 123
816 15 123
856 17 123
868 17 123
852 19 123
1096 21 123
2188 19 122
2352 32 118
1600 18 118
1008 12 116
752 15 116
796 14 116
788 16 116
804 14 116
816 13 116
776 14 116
800 14 116
796 14 116
792 14 116
804 14 116
812 14 116
796 14 118
800 14 120
796 14 120
816 14 120
808 14 120
804 14 122
796 14 122
800 14 122
804 14 122
800 14 122
792 14 122
804 14 122
804 14 122
800 14 122
808 15 122
828 15 123
844 14 123
836 15 123
1500 27 123
1572 29 123
884 23 123
988 11 123
812 14 123
816 21 123
1372 27 123
1424 30 123
1596 25 123
1932 26 123
1960 23 123
2356 19 122
2540 19 116
3172 14 111
4168 12 104
5572 14 98
6700 17 93
4700 12 93
5228 13 91
5712 13 91
6044 14 89
6388 16 87
6220 12 87
4816 12 87
4920 12 87
5112 12 87
5300 12 87
5500 14 86
5680 13 86
5852 22 86
5628 36 91
5500 35 95
5368 35 96
5228 34 98
5076 34 100
3796 33 100
2760 22 100
1760 23 100
1424 18 100
1260 15 100
1192 14 102
1180 14 102
1168 13 102
1152 13 102
1176 14 102
1192 14 102
1184 14 102
1160 13 102
1144 13 100
1128 12 100
1104 12 102
1108 12 102
1044 10 102
1132 13 102
1144 12 102
1136 13 102
1252 15 102
1228 13 102
752 13 102
872 15 102
900 16 102
880 16 102
988 27 100
1568 13 100
760 11 100
896 10 100
792 11 100
768 12 100
792 12 100
776 12 102
784 12 102
800 12 102
784 12 102
784 12 102
784 12 102
788 12 102

 

[jgp321]

Those are very high intake temps. Those kind of temperatures will definately lead to knock.

 

[yukondoit]

also my afc settings are +12 all the way across just to keep the knock down. but my low map is zero because my fuel trims are less then 10. I dont know why its knocking so bad at only 15 psi.

 

[TSIMonsteR]

phantom knock, maybe? Also, some of that timing is getting pulled due to the intake temps. It starts pulling after anything above 108*

 

[Joesmoke]

Intake temps high-Timing pulled.
Possible real knock-timing pulled.
Phantom knock-timing pulled

However, your timing is not that bad. I see a peak of 17 at the high end of runs when the temp dropped. Could be better though.

+12 on SAFC? Is your chip calibrated for the 750 injectors you run? If so, I would think that would be too rich, causing the car to be boggy. But that could only be confirmed from a wideband. Could be a cause for your increased IDCS you posted elsewhere.

Using fuel to quench knock will only work so long. Your choice would then be boggy rich (slow), or timing retard from knock (slow). Even possible rich knock.

15 psi should be reasonable for the stock smic to handle for a 1\4 mile pass, even with the evo 16g. Fuel should be adaquate as well-maybe even pretty rich.

Full exhaust will help prior to intake pipes. Then pipes. In this sense, the upgrade paths work well. You have to get that exhaust out faster then the stock pipes allow.

So, start by getting those intake temps down. Next upgrade? Has to be exhaust. Dont be a wimp and just get 3" all the way back

 

[yukondoit]

yea i figured as much, thinking to much back pressure and its increasing the combustion chamber temp. thanks for the help, ill order up an exhuast this week and report back.

question i have about an exhuast is there a way to get rid of my second o2 so i dont through a code?