2006 Chrysler 300c SRT8 st kr question

[kylar1207]

Hello fellow forum members! This is my first post here and I have a question regarding short term knock retard.

I'm totally new to the Predator, so please be patient with me.

I just received my U7135 Predator with the latest and greatest CROM currently posted on the Diablo download page and loaded the 91 oct CAI tune on my 2006 Chysler 300c SRT8.

I took her for a spin last night and decided to check out the data logging feature on the tool.

When I returned home, I loaded the dataviewer and played back the data log. I noticed in a couple of spots in the log at WOT I was seeing anywhere from 3 up to 8 of short term knock retard in the 4,000 to 6,200 rpm range.

I've read on this forum that anything over 3 of st kr is not good. I'm wondering if adding fuel in the above rpm range is the way to address this issue.

I'm running 92 oct Chrevron fuel which I think is the best brand in the Olympia, WA area. We also have Shell and Conoco Phillips. We don't have the branded gases that I've seen referenced on this site as the best for the Predator application.

I'm currently not running a BT catch can, however, I have one on the way from BT and should be here is a few days. I understand that the catch can may help with st kr by eliminating deposits from entering the intake.

Should I wait for the catch can and data log again before messing with the fuel adjustment or do you think it would be ok to go ahead and add fuel in the applicable rpm range and log again?

Thanks in advance for your advice!

[kylar1207]

Catch Can installed and logged again.

Still getting st kr at the levels previously posted at WOT in that RPM range.

I'm going to go ahead and add fuel in the range I'm experiencing st kr and log again.

Will post again to let you know what the results are.

If I'm barking up the wrong tree, please let me know.

Thanks.

[HerDaytona]

It would be nice to know if you have a 180 t-sat. Lowering your engine temps helps alot also. Going to what is called a 180 t-stat is actually a 186* stat. Autozone or Oreillys can help you out. Just ask for a cross of a "#4128" t-stat. Lower some fan settings. There is a post just above or below yours tonight that addresses fan setting. Copy them on your Diablo. Not sure what Cold air intake you are running. Just a little helpful info for you. After getting temps down you could log again it is good you figured out how to log that is just part of the game. You might just go ahead and add about 3/5/7% of fuel with the t-stat and run a log from there and see what you have. Just spent the last part of the truck race this afternoon helping a buddy get his 300C logged and fuel added to rid his ride of knock.

Enjoy
Tom

[HerDaytona]

Wow kylar we were posting at the same time.

[kylar1207]

Thanks for posting a reply Tom!

I do have a Jet 180 t-stat with a AFE Stage II CAI installed. I've adjusted the fan settings to 185 ls and 195 ms & hs for both AC on and AC off.

I added fuel at 2/4/6%. It seemed to help the st kr but now I'm getting lt kr.

The roads here in Olympia are a bit wet and I'm not able to hook up very well at WOT. I have no clue whether that makes a difference.

I'm going to lean it out a bit tonight and log again tomorrow to see what happens.

It seems all the other PID values I logged are within the range that are displayed on the dataviewer, but what do I know?

If I should be focusing on one of the other PID's to get this thing dialed in, please let me know. I'm logging the PID's in Johan's sticky.

I'll post again with results of my experimentation with this cool tool!

Thanks!

[Mike_Levy]

You installed the catch can, but did you pull the intake manifold and clean the oil and sludge out of it? You're gonna need to do that. An 06 is probably completely loaded with crap and gummed up.

[HerDaytona]

Kylar what ^^^^^ Mike said. You do most likely have oil in the bottom of that intake. That causes Knock retard. Now short term turns into long term knock retard. Then short term comes back if it is present. Seafoam is good to use on the intake. I would not lean out the fuel from where you were at.

[kylar1207]

You installed the catch can, but did you pull the intake manifold and clean the oil and sludge out of it? You're gonna need to do that. An 06 is probably completely loaded with crap and gummed up.

The intake is clean. I took a good look when I installed the AFE Stage II CAI about a week ago.

The car only had 11,500 miles on it when I bought it back in July of this year.

She has about 15,500 on her now.

If I do go ahead and clean the intake to eliminate the possibilty of build-up not easily seen by looking into the throttle body, do I really need to pull it or can I just run a can of Seafoam through her?

Thanks for the replies guys!

[HerDaytona]

I would think that if you do not see a puddle in the back of the manifold then just add more fuel and log again. Johan has said you can log for knock retard and add fuel and you will be close on the Air Fuel ratio.. Then put on the rollers and get her dialed in on the nut.

[kylar1207]

It's me again.

I ran a half can of Seafoam through the intake for good measure, but I have another question.

People seems to be saying add fuel to eliminate the kr I'm experiencing, but what about adjusting the timing by playing with the spark adjustment?

I noticed this info posted on the U7135 product page that talks about adjusting parameters.

"Knock Retard, this is the amount of timing removed (in degrees) due to knock (detonation/ping). The knock sensors can in rare cases pick up other harsh engine noises as well, if this is the case it is recommended to fix the cause of the noise before proceeding.
You basically always want the knock retard to read zero under wide open throttle conditions, it is normal for it to show some KR when stomping on the throttle and also during the shift.
Monitor the spark and the knock retard pids under wide open throttle and see if you have any knock retard, anything higher than 1 should be adjusted in the respective timing range in the Predator , if the knock is severe, 5 deg plus, try lowering spark by 10%, if less than 5 deg, try 5%. Make another wide open pass and monitor the same pids and basically keep doing this until you seen no knock retard."

Anybody want to chime in?

Thanks!

[Mike_Levy]

We generally only screw with the spark if the gas is no good. You'll know if its bad. If after adding fuel, the knock goes up, you know the gas is the problem. In that case you'd reduce spark. If it goes down, adding fuel is better for power then cutting spark.