Join Date: Mar 2012
Location: Kyle, Texas
Thanked 449 Times in 334 Posts
Feedback Score: 0 reviews
If you're getting ST KNKs in closed loop (partial throttle) you need more octane. Chances are that adding fuel won't get rid of the ST KNKs in open loop (WOT) if you’re getting KNKs during closed loop operation. I would try some 93 octane and see if it reduces the closed loop KNKs. If it does, then adding some fuel in open loop may work. It takes quite a few miles of higher octane gas to see the difference so you'll have to drive her a bit then log.
The 6 to 7 ST KNKs with the stock tune doesn't seem right to me. What octane does the 5.7 require? If it is 91, then I can understand the KNKs as you are running too little octane. If the manual says 89 octane and you’re seeing that many KNKs on the stock tune, red flag...
I wonder if you’re getting false knocks from a rattle or loud exhaust or bad KNK sensor.
As long as you’re getting KNKs, you won't benefit any timing advances from the tune as the ECU is pulling it right back out.
If it were my car, I would see what octane fuel I needed to get zero KNKs with the stock tune (both closed and open loop) and go from there. If you load the 91 tune you may need to run 93 octane fuel to not have the KNKs. Could be as simple as the ethanol in the gas that you are using or it could be a sensor issue but 6 ST KNKs on the stock tune isn’t right…
Your log graphs must look like an EKG when in reality you want them as flat as possible through all three tuning ranges.
Yes I know we can only adjust the WOT.
I am getting up to 3 ST on partial throttle but im not too worried about it as its not really hurting anything. I was getting up to 6 or 7 on the stock tune running 89 octane.
I with work, GTA 5 and Battlefield 4 I probably wont get a chance to get a good log in lol.
Mike over at DS said to adjust fuel before reducing timing and that 5% isnt that big of a difference. So I assume you should just keep adding 5% until you are nearly maxed, then pull by a degree or two.
'12 A5 SRT Mods: Mopar CAI, Corsa Sport Cat-back, 180 stat, B&G Tuned ECU, DRs (Hoosier 315/35/17") 430/434 HP/TQ
PB 1/4 mile: 11.7344 @ 116.19 MPH with a 1.7011 60'
PB 1/8 mile: 7.5086 @ 92.46 MPH