Diablosport Forums

I recieved my trinity this weekend, along with my LMI 4 intake. My car is a 2008 challenger SRT

I wanted to monitor knock, and a few other variables on my stock tune and intake before so that I could compare to the after tune and intake

I noticed a lot of ST knock at half throttle around the 2k rpm range. I then installed the intake and the 93 tune and it only got worse.

Now, I know that the 93 tune doesn't do anything for non-wot driving so, my question is: is 2-3 degrees of ST normal?

If not, then I guess it's time to try different gas and maybe some new spark plugs

I loaded up a few logs into the data viewer so that I could more specifically see what's going on.

It looks like from 1700 - 2100 my ST KNK bounces from 3.0 - 1.0. Throttle is 40-50%

After the tune, the same KNK seems to be present. Also, after the tune it looks like I am getting some WOT KNK in the upper ranges. I will try adding fuel in those ranges.

As for the non-wot knk, I'm not entirely sure. It seems very consistent in that range.

So, I figured I would post my on going troubleshooting as I know I'm not the only one with Knock issues.

Yesterday I had to take the car to the dealer, so I loaded the stock tune. I also put 20.00 worth of a different fuel brand (Marathon 93) - The stock tune seemed to like the new fuel a bit better. Knock fluctuated, but was almost always 0 with occasional spikes up to 2.0 but fell quickly.

So, I then loaded up the 93 once again and am getting more Knock at partial throttle than at WOT (I adjusted the WOT specs to address the knock at WOT).

The Knock spikes as high as 4.5 but at cruising its always 0. Also, it hasn't registered any LT Knock.

My next step is to add Quality octane booster to the fuel to see if that helps. If it does, that tells me I need to source better fuel, or that the fuel in this area just cant handle the 93 Tune.

Once I do that, I am going to fall back to the 91 Tune with 93 octane fuel to see if that helps.

I may be totally over thinking all of this. Maybe this level of knock isn't anything to worry about . . it's only concerning because the stock tune has clearly less knock.

Oh, I also ordered a speedlogix Catch Can. When I installed my CAI this weekend, I noticed some oil in the intake. I'm sure that's not helping the knock issue at all.

Hopefully the catch can helps a bit as well.

captain_marvel wrote:Oh, I also ordered a speedlogix Catch Can. When I installed my CAI this weekend, I noticed some oil in the intake. I'm sure that's not helping the knock issue at all.

Hopefully the catch can helps a bit as well.

clean the oil out of the manifold!

mikel wrote:

captain_marvel wrote:Oh, I also ordered a speedlogix Catch Can. When I installed my CAI this weekend, I noticed some oil in the intake. I'm sure that's not helping the knock issue at all.

Hopefully the catch can helps a bit as well.

clean the oil out of the manifold!

What would be the best way to do that? I don't particularly want to remove the manifold - But I will if I have to

Pumped a tank full of 93 and then added 3.1 octane booster for a theoretical 96 octane. This seems to have made the ST's less jittery at partial throttle.

I guess this leads me to believe my base gase isn't that great ...

Or, perhaps I need to go a step cooler on my plugs? Or maybe I'm just paying too close attention to it all ....

captain_marvel wrote:Pumped a tank full of 93 and then added 3.1 octane booster for a theoretical 96 octane. This seems to have made the ST's less jittery at partial throttle.

I guess this leads me to believe my base gase isn't that great ...

Or, perhaps I need to go a step cooler on my plugs? Or maybe I'm just paying too close attention to it all ....

Your knock sensors could be picking up noise from in your engine bay. Are you hearing pinging? Or is this just from what you are seeing on your logs?

captain_marvel wrote:

mikel wrote:

captain_marvel wrote:Oh, I also ordered a speedlogix Catch Can. When I installed my CAI this weekend, I noticed some oil in the intake. I'm sure that's not helping the knock issue at all.

Hopefully the catch can helps a bit as well.

clean the oil out of the manifold!

What would be the best way to do that? I don't particularly want to remove the manifold - But I will if I have to

remove the throttle body, get a rag, reach in and wipe out the intake manifold.

if your hands are too big to do this, find someone whose hand will fit thru the intake opening.

BTW, up to 2 or 3 degrees of ST knock is fine.

3+ degrees of ST knock needs fixing, IMO.

you may get best results by using 93oct gas and 91oct canned tune.

or get a custom tune.