Valves hitting? Or am I Detonating?

under WOT around 5000RPM’s I can hear a loud ticking. Kinda like when you tap the tip of a screwdriver flathead to a metal, probably 10 ticks a second.

I have read from a magazine that detonation will sound like a marble inside an empty soda can.

I have tuned the car and from 4500 to 6500 my air fuel ratio is steady at 12 - 12.5

I have also did a valve adjustment a year ago.

Thx for the future inputs!

how much timing are you running in that area? what is your peak timing? what heat range plugs are you running? run at least a 7, you can run 7-9. when tunning, I run 11.8-12.2a/f but never higher. you might wanna richen things up a bit.

P.S. if your valves hit, your engine stops running. then you have to pull the head and replace the bent valves.

As for timing I have to get back at you but I will post up the dynograph from my dyno tune 3 weeks ago.

I’m running BKRE7’s NGK’s right now by the way and I just cleaned my 02 sensor.

Sometimes I also hear intermittent tapping coming from the valve cover. Like, tap, tap, tap, tap, 4 taps, but not all the time.

Here’s the Dynograph from 3 weeks ago:

Hmmm, It says BROWN is trq, Which show about 160

And it shows BLUE is HP,
and it shows about 158

Now, I have come over many mnay thread saying
It is imposible to have more tq than HP.

So whats up with the graph?

As for the graph I have no idea why i have more TQ than HP, I never heard that it’s impossible to have more TQ than HP.

But anyways when I got my car tuned i was running 94 octane and then after that I’ve been using 91 octane. Could this be it? I will try to empty my tank and fill up with 94 and see what happens, thx

that statement is untrue.

dodge viper has more tq. than hp.
pontiac firebird also has more tq. than hp.

jaylo: sorry for going off topic there. just wanted to clear up misinformation

Yeah, you’re right, that’s some serious mis-information there. My '99 Chevy S10 came out of the factory with something like 240lb trq and 175hp. I miss that truck… :burnout:

he was prob. saying it is nearly impossible to make more torque than hp on an LS. IMO you have a seriously hurt engine, or a seriously SHITTY tune. :up: that peak in A/F at 4100 is no good.

quite possibly. his statement wasn’t realy specific enough or indicated that he was talking about an LS.

Yah, I have heard that on Hondas etc.
As the engine are diffrent, that this is the case.

I’m saying that On Hondas this isnt possible. :shrug:

I’m going to ask H-T cuz I’m at school and I’m bored.

Also, Thank you for trying to clear things up for me.
You and I both want true information.

the saying is true for hondas but that’s nto all of it.

It’s a honda can’t make more torque then horsepower after 5225rpm

I have tried to use 94 octane instead of 91 octane (thinking I can get away with it since gas is expensive). Then no more detonation!

I would have known since my car was dyno tuned under 1/4 thank of 91octane and 1/2 tank of 94 octance…

I have also found out why I was smoking really bad under high temperature. The exhaust side of my turbo is leaking oil hence the pale white smoke. Time for a new turbo, but that’s next yr.

Whats your setup,

More important question is what turbo are you useing?
xs Power? if so yes they tend to need rebuilding often

No sir, I’m using at T3 roller bearing turbo from an RB20DET

If you’re hearing that sound under those throttle conditions I vote detonation.

off topic but, how do you have a SIG?

he is a PREMIER Member,
You pay what like $20 (correct me if I’m wrong)
a year it goes towrds running this site
and keeping it up for all of us :clap:

you get thing that the normal user (you and I) don’t.

well worth $20. I was wondering, why on this site, there are no sigs.