Help with tune and ST KNK

[tomssrt8]

2007 charger SRT8.
I've just installed the 180 deg thermostat and BT catch-can and am wondering what temps to set the fans on. Seeing we live in a colder climate my engine doesnt seem to get past 83/84 deg C (181/183F). I've also noticed far more ST KNK retard in the data logs and the car seems lazy off the line, I am using shell v-power 91 oct. I had increased the WOT fuel to 5%-5%-5%

With the car at 176 deg and I floor it the ST KNK goes up to 4.5 and varies up & down thru the whole run. After the car is up to 183 deg I dont get the immediate ST KNK when I floor it but at 3700rpm the ST goes to 1 deg then up to 3 deg at 5300rpm and stays there thru the whole run (14 seconds).
I am thinking that maybe the engine isnt reaching optimum operating temps and might put in a 190 deg Thermostat instead as I never had this problem
with the original thermostat.

[bob34787]

a few other people with the srt have also removed 1 degree of timing at all levels along with the 5% fuel and this seems to eliminate the KR

[bayville-ss]

Pardon the dumb question but what is KR? I have an 06 SRT Charger with 93 CAI tune. Should I or could I pull 1* of timing along with 5% fuel? Will this help with performance without hurting anything? I have no idea how to data log and no laptop. Should this be done 1st? Thanks

[bob34787]

sorry, Knock Retard, you do not need a laptop to datalog, you can record your st knock retard for a few WOT runs and play it back on the predator, or download it to your home pc. Yes you can reduce timing and it won't hurt anything, however you may want to log your st knock first and see if there is a need to change it.

[Quick]

Pardon the dumb question but what is KR? I have an 06 SRT Charger with 93 CAI tune. Should I or could I pull 1* of timing along with 5% fuel? Will this help with performance without hurting anything? I have no idea how to data log and no laptop. Should this be done 1st? Thanks

I'm hesitant to say anything for fear of offending people. So, no offense intended. The first thing people should do is really understand how all or most of this works before changing things. DiabloSport claims the canned tunes are safe and pretty damned good. They've got a lot of experience and a good track record in the area of performance cars and tuning. Why would you go and blindly make some changes for a problem you don't know you have and don't know what it is?

To directly answer your question. You could add 5% fuel and you could pull 1* of timing and you will not hurt anything. Will it help with performance? No way to tell without any information. Answer this: why do you think you're not perfectly/optimally tuned right now?

[tomssrt8]

Well I ended up adding more fuel in the 3 ranges. In particular, 10% 12% 14% and now I only get a minimum amount of ST KNK at the shift points. I get no LT KNK. I guess with the catch can installed I am getting better air into the intake and it was running leaner. Only my opinion.

[Mike_Levy]

I'm up in the same area, 6%, 10%, 10% and timing retarded a degree in all 3. Still getting some minor knock on the very top end at higher speeds.

[Illss1]

so when u ADD FUEL on the predator it goes "-" correct? I thought RICH is adding fuel but it confused me because of the (negative) "-" when u slide left ...... Sorry to threadjack but am i making sense? Lean will look like its positive when it should look the otherway around .

[MagnumSRT8]

I got rid of most of my knock. I had to add 6% on the low end, 16% mid and high thats running 94 octane on the 93perfCAI tune. I get a small blip of knock around .5 but thats it. Didn't pull any timing and peaking around 26-27degs timing. Ran a 12.72@110 at the track with a air hammer, exhaust and a jet 180 thermostat.

[Quick]

so when u ADD FUEL on the predator it goes "-" correct? I thought RICH is adding fuel but it confused me because of the (negative) "-" when u slide left ...... Sorry to threadjack but am i making sense? Lean will look like its positive when it should look the otherway around .

It looks like you're using v16? They made it clearer starting with 8r20 and most everybody who has upgraded to 9r04 is really pleased with it. Why not upgrade?

I started with 8r20 so I don't know what the v16 display looks like. On the later versions the display is labeled "RICH" to the left and "LEAN" to the right and it is referring to fuel.

I THINK (don't know for sure) on v16 the "-" and "+" refer to the AFR number that you're affecting. If you start at 13.0 and make it richer you go to 12.0 so you're going "-" on the AFR number. How's that?

You really should get a wideband gauge.

[Illss1]

i may upgrade just to be able to log and on v16 its actually labeled how ur saying it but was curious as to WHY when i slide to the rich it would say for example -5 when i thought ur adding not taking fuel but it's cleared up already and i understand how this works now ... thanks guys .