Knock

[MattR]

I have a 2011 with a KB 2.8LC and have been working with Lund Racing to dial in a tune. For whatever the reason my car gets knock activity in the mid range. I've tried different sources for 93. BP right now. A can of Torco. Bob's oil separator pass side only and still have it. I just ordered abother colder range of plugs and a drivers side Bobs unit is there anything else I'm missing? Car is at 18.4 lbs max just before redline, most of the pull is around 16 lbs. It has cooling mods, headers, no cats.

 

[GT500RedStripe]

Is there any chance that something is rattling against the motor that the sensor is picking up as engine knock? Maybe a header touching the steering shaft or some aftermarket component?

 

[MattR]

I have looked it over pretty well. I don't see or hear anything. I did have oil in the original SC in the back and on the throttle blades. Lund seems to think that's what the issue is.

 

[nxhappy]

Lund will fix it. Maybe you are running too much advanced timing.

 

[cluscher]

What are head and coolant temps?

 

[MattR]

Coolant is 180. Can I see the specific head temp in a data log?

 

[cluscher]

Not sure if that is a parameter you can read on the 11? I can on my 07. Coolant is obviously good. My head temps generally run about 10-12 degrees hotter than coolant temps under normal driving conditions.

 

[Bobbyblaze]

My car would show 3* of knock at tip in, which could have been from me having the stock goodyears and the tires spinning creating false knock, or the transition from going partial throttle to WOT can also create false knock. Can you actually hear this knock or is it only in your logs?

 

[MattR]

It's only in the logs.

 

[1320 Junkie]

Need to log timing and see what its doing. He could have global base to high or global spark adder too high....sounds like 1 or both are happening causing knock if theres nothing rattling around on top of the engine. I have seen a 3/8 extension left in the intake valley cause this as well in my buddies car....was pretty funny actually.

 

[nxhappy]

He could have global base to high or global spark adder too high....

I was thinking this as well.

OP, can you post some data logs ?

Typically you can hear knock, but not always. Especially if you have a loud exhaust lol.

 

[MattR]

I know how to post pictures. How do I post a file? Yes my exhaust is loud, no cats and SW exhaust. It would be very hard to hear it.

 

[MattR]

View attachment forum post - Copy.pdf

I hope this worked well enough for you to see whats going on.

 

[Spectre500]

Knock sensor going off

I'm having the same issue. about 3* during 3rd gear pull and a hard 2nd to 3rd hit. TR6 Spark plugs gapped to 0.28, have Bobs separators and also running the C&R competition dual fan unit. Question for the OP are you running the 168mm? The gimme 5 intake tube sits very close to the DS valve cover and I put a piece of heat resistant fiberglass tape under it to help shield it. I also had to use the 3/4 inch drop mounts to get the 1/2 clearance between the SC and hood. Im wondering if somethings touching during a hard throttle open.

I'm going to put her on a lift today and go over the exhaust and look her over.

 

[MattR]

Yes I have the same set up. And yes the intake is very close. I'll see if I can insulate it with something. Thanks.

 

[nxhappy]

View attachment 28007

I hope this worked well enough for you to see whats going on.

ummmm.....it appears your fuel pump duty cycle hits .48-.50 .....which means you are completely maxed out !

Are you running the stock pumps without a BAP ? and what are your mods ??

 

[MattR]

BAP and ID1000 injectors. Odd that lund wouldn't notice that and that this combo would need that much fuel? I'm sure I'm lucky to be at 700rwhp?

 

[MattR]

Full list of engine mods are revan heat X, ARH long tubs with off road H, KB 2.8 LC kit with 3" pully, 168mm TB, over sized heat x coolant tank. TheN just supporting drive train mods.

 

[Spectre500]

Matt do you have an aeroforce interceptor guage? I've been monitoring mine and I get zero activity on a neutral rev log, but once I accelerate I get 1 to 3 on the knock retard. I'm not familiar with that and am wondering if that positive 3 means its decreasing timing by that amount..??? I looked over the exaust today and nothings touching anywhere. Next step will be to run a can of Torco and put her on the Dyno to see what she does. JL jr seems to think its false knock coming from the SC or from the exaust logs. Long tubes are going on my car next week maybe that will cure the activity.

 

[99SSls1]

Drop some unleaded 100 octane in or similar and all your real knock should go away.