Stan

Me and a friend are having different opinions.. I say you car hear detonation on a boosted motor.. he's saying that you can't, only on n/a motors.

Any of you guys hear detonation on your boosted engine before you blew it to pieces?

Stan

FooK

detonation can be heard on both.

J-SMITH69

never heard it, broke 8 pistons and one sleeve

Reddy

You can have detonation without blowing your motor to pieces. My Civic detonated countless times and its still running strong, there's just a limit and it'll eventually go

Stan

By the way, i'm talking full exhaust, not open downpipe.

Stan

daubleaaron

I have definetly hear detonation on my boosted a6 with full exhaust.

FooK

i was always detonating on my d15b with the greddy kit and full exhaust, all the ------ time... was very audible...sounded like marbles in the cylinders.

hotrex

i detonated my old a6.... sound is unmistakeable made me sad.

baldur

The only PROPER way to detect detonation is to use a stethoscope bolted to the engine.
Time for a little writeup.

You take a pair of ear protectors and drill holes in them, then epoxy hose barbs or pipes into them and connect an 8mm fuel line to each.
Then you tee them together and run an 8mm fuel line into the engine compartment. At the engine you take a 10-15cm piece of copper pipe that the fuel line fits right into (pipe slips over the fuel line) and you squash the end of the pipe, drill a hole in the flat end and fasten it to your cylinder head or block somewhere.
I've used this on a few engines, it's very sensitive and makes it very easy to tell detonation from all the other sounds, even with a loud exhaust.

BLAAST

It's true that you can ear it but sometimes, if you are not lucky, there is a level of detonation that is too subtle to be eared and is still very damageable for the engine. I did see cars that were running strong with no noticeable detonation and they still blew the ringlands in a few days.
I'm sure BALDUR'S stetoscope would have helped in those cases!! That's a very good idea!

Me, I am using the J&S safe guard. It's the best way to avoid detonation while have the smallest possible margin of security.

This computer has the usual "BTM" function but is also connected to the factory knock sensor (or one you added) and when it senses detonation, it is able to calculate in which cylinder detonation is ocurring and it retards the timing on that single cylinder as much as necessary to stop the detonation. up to 20° of retard actually.
When the leds light up, it's not to tell you you have detonation. It'S to tell you that your timing is currently being retarded to avoid it.
Then, it's up to you do make the appriate fuel and timing adjustements so the J&S no longer has to save your life. With this system, no need to run unecessairly retard timing for added safety. You can stay at the leading edge of timing advance and a/f all the time.