Help me with ignition knock (UPDATE)

[BAH2SS]

Originally Posted by Greenhornet2

95 RON is probably a bit too low octane. Since you are fooling around you might pull even more timing and see if it changes the knock, I am thinking you have something physically making noise and the knock sensors are picking it up and it is not a true ignition knock. I do know there is also a way to reduce sensitivity of them but if you are actually hearing a knock then I wouldn't mess with that.

I am going back to 98 RON to see if it makes any difference, the thing is that the car is low mileage and completely stock the only thing is that i deleted the cats, no idea whats wrong with it. My 2010 camaro used to drive with 95 or 98 octane with no issues. had a pontiac G8 that i always used 95 oct never had a knock.

[BAH2SS]

Can anyone help me out and share the stock tune for a 2015 1LE, i dont have access to the repository of HP tuners. I do not have the stock file also because it was already tuned by another guy before us. I'll try to compare what we have with the stock map. We've been comparing to a 2014 SS, we're guessing that there might be a difference between them.

[acammer]

Originally Posted by BAH2SS

Can anyone help me out and share the stock tune for a 2015 1LE, i dont have access to the repository of HP tuners. I do not have the stock file also because it was already tuned by another guy before us. I'll try to compare what we have with the stock map. We've been comparing to a 2010 SS, we're guessing that there might be a difference between them.

I'll grab that and send it to you. PM me your e-mail address. And then, when you get my e-mail send back your latest tune and a log, I'll have a peek and see if anything stands out to me. Audible knock is really strange - and even stranger that the knock sensors did nothing to pull the timing, hard, at that point. I'd be careful rattling it with knock too much if it is real - you'll end up spitting out a ringland or something and then it gets ugly from there...

[BAH2SS]

UPDATE:

So i kept doing WOT throttle pulls and started using 98 RON fuel again i've been noticing that the KR and knock is getting less. decided to inspect the pistons for carbon build up with a camera and found some carbon that are breaking up. kept doing WOT pulls and so far cannot hear a knock and the logs dont show any KR in 2nd, 3rd and 4th gear. 5th i get 1-2 degree but i cannot hear any knock.

currently it starts at 18 degree of timing and ramps up to 21 degree at 6300 rpms.

replacing the thermostat and installing K&N drop in filter and will do one last dyno day and will update this post.

[acammer]

Originally Posted by BAH2SS

UPDATE:

So i kept doing WOT throttle pulls and started using 98 RON fuel again i've been noticing that the KR and knock is getting less. decided to inspect the pistons for carbon build up with a camera and found some carbon that are breaking up. kept doing WOT pulls and so far cannot hear a knock and the logs dont show any KR in 2nd, 3rd and 4th gear. 5th i get 1-2 degree but i cannot hear any knock.

currently it starts at 18 degree of timing and ramps up to 21 degree at 6300 rpms.

replacing the thermostat and installing K&N drop in filter and will do one last dyno day and will update this post.

That's a definite improvement. Significant carbonization could definitely cause some knock. Sounds like you're on the right track.

21* still seems low, I would think 2-3* or more is where it would make peak power, with a bolt on car, but it depends on the combination and fuel. If you're on the dyno anyways I would feed it a couple degrees and see if it picks up and stays knock free. If you're just tuning on the street, it's gonna be real hard to knock if those few degrees are worth much.

[Russell James]

Do a top engine clean using a bottle of techron in the fuel tank. Floor it a few times during that tank. Then change the oil, it will be black. Chevron with Techron is a good cleaner to use.

[Aqua Blue RS/SS]

Sea foam works really well too if you can get it over there.

[BAH2SS]

Originally Posted by acammer

That's a definite improvement. Significant carbonization could definitely cause some knock. Sounds like you're on the right track.

21* still seems low, I would think 2-3* or more is where it would make peak power, with a bolt on car, but it depends on the combination and fuel. If you're on the dyno anyways I would feed it a couple degrees and see if it picks up and stays knock free. If you're just tuning on the street, it's gonna be real hard to knock if those few degrees are worth much.

I am going to increase the timing for sure and see where it picks up knock again. I am doing dyno tuning with street logs after that. The car is stock with just a cat delete and a drop in K&N filter.

Originally Posted by Russell James

Do a top engine clean using a bottle of techron in the fuel tank. Floor it a few times during that tank. Then change the oil, it will be black. Chevron with Techron is a good cleaner to use.

Unfortunately I cannot get techron/chevron products here, BG's are available as cleaning solution and other cleaners like cyclo, liqui moly... etc

Originally Posted by Aqua Blue RS/SS

Sea foam works really well too if you can get it over there.

I've been looking around here for sea foam though can't get them here. We dont get any of those well known or the products which actually work around here. My only solution was to get the best octane fuel available and keep doing WOT pulls to burn off the carbon deposits.

I might be able to get hold of AC delco upper engine cleaner but i have no idea if it works as well as techron stuff.

[Aqua Blue RS/SS]

The bg tip end cleaner works good if you can get a hold of it, run it thru a vacuum line like you would sea foam.

[John_C]

You said there was some oil in the intake...

Does you car use much oil between oil changes?

Any oil getting in the engine degrades octane, so I would at the very least get a catch can like the Mishimoto.

Was $260 now on sale for $195

I was shocked as crap when I seen how much oil my catch can caught.

[acammer]

Originally Posted by John_C

You said there was some oil in the intake...

Does you car use much oil between oil changes?

Any oil getting in the engine degrades octane, so I would at the very least get a catch can like the Mishimoto.

Was $260 now on sale for $195

I was shocked as crap when I seen how much oil my catch can caught.

That's a very good point. Oil will degrade the octane content of the fuel charge, and will reduce the threshold for knock. I have an older 2-port Elite Engineering catch can on my car, and it catches a decent amount of oil, I drain it at each oil change. Definitely something to consider.

[Greenhornet2]

Water works just as well as any cleaner. Ever seen a cylinder after its had a blown head gasket for a while? It is pristine. Water will steam clean the cylinders. No need to purchase seafoam or any of that BS if you are running it through a vacuum line.