I listened to it, but I couldn't really tell much. I almost thought I heard our old friend the cam chain "knack, knack", but it just wasn't a good enough sound quality for me to tell.

 

I put in the headphones to hear as well as possible. The quality isn't bad. But I'm not sure I heard the knack knack. Instead of just blipping the throttle, could you slowly rev it up to around 6K and back it back off? FWIW...?

 

If it's not raining today after work...

The pre-ignition sound is very noticeable at times, like I said, stalled the engine in the parking lot here, trying to adjust the idle to possibly fix it.

It will sound normal if I slowly rev it up, roll on smooth and off smooth.

The engine probably sounds loud because the camera is right next to it, and because the engine is loud compared to the stock exhaust.

 

If it really is a detonation issue, high octane fuel should stop it. It it doesn't, then something else is wrong (like timing?). In my experience, detonation is usually most pronounced in a lugging condition at lower RPM (like slowly accelerating in too high of gear), not at idle.

 

Good grief, Scott...your injury-induced cabin fever must be sitting in...probably sitting around in your underwear with your headphones on listening to engine sounds...oh the humanity!...LOL!

 

hahahahahaha

 

https://vimeo.com/38606191

New video, can hear the sound a lot better in this one, since it was far more pronounced.

 

Well, it's been awhile since I heard the cam chain rattle, having installed the manual tensioner. Still, I think I'm hearing some cam chain noise. But hey...I'm old, and I think the batteries in my hearing aids are almost done.

 

Shouldn't be cam chain. It's a knock, not a rattle.

 

hmm, I am old as well. Sounded like valve train related to me.