I thought this was interesting reading. It's interesting to see how a professional tuner uses knock as tuning tool.

http://www.apexspeedtech.com/using-k...-to-your-motor

 

You thought wrong. There was no useful information in this article. Unless part 2 comes out with something useful, this one's a dud. I've been looking for a lot more information on professional tuners and det cans, but there's not as much out there as I would like.

 

what do you want to know about using a det can and tuning?

 

This article mentions that during tuning, one can purposefully cause detonation in a way that is relatively safe in order to find where the line is. Anyone know how that is done or whether that statement is accurate?

 

sounds like the author is saying you can learn what detonation sounds like by letting it happen at a light load instead of during a WOT pass.....

 

thats what i get out of it

basically you want to slowly add timing in, and keep making pulls. sooner or later its going to knock. and sometimes, it will take a long while... sometimes it will stop making power long before it will knock.

but one thing is for sure, if its knocking, bad things are going to happen quick.

so when you hear knock, listen for the RPM/load its knocking at, dial back the timing, and repeat.

doing that PLUS having a dyno can make it a lot easier to dial in the timing maps.

 

From what I was told and witnessed while tuning was pretty interesting. doing pulls on the dyno take a note at the dyno results and notice the upper rpm ranges, if you see waves/fluttering you can increase timing .. It would be nice if I had examples of this but I don't on hand.

Hp should keep gaining as you add timing, then flatten out, then you should hear audible pinging/knock. I do not know what the threshold is between HP flatting out and audible knock... off hand I would have to guess it has to do with compression ratio and rpm...

To be safe you want to find that point at which hp output stops gaining and back it off a bit Just because you cant physically hear the knock/ping/bb's in a can does not mean there isn't any.

You can do this for all rpm ranges not just WOT tuning "the last 3 columns" might manage to pick up some more torque down low.

I manage to run about 31 degrees at WOT on my JDM H22a stock guts inside..

--Aaron