I've got hotcam, headers, and non self aligning rockers. I don't want to eliminate the KM with tuning I was just wondering if there's a way to make it so that a certain level of knock doesn't do anything and anything past that does. Like tuning it to act like an LT4 km.

 

No. It has an attack rate but nothing that changes what activates it. There is a way to put a resistor setup on the pcm wires to adjust to decrease its sensitivity. I actually made a box with variable resistors that I can use to adjust it.

Hal

 

I can't exactly build one of those. Would it just be easier to get an LT4 KM? I'm thinking of going boost soon and I really want to have that sensor accurate for logs and don't know if LT4 KM is the best way to block out the false knock.

 

Do you have lt4 heads? If you don't then I doubt your setup is even similar enough to need it (lt4 heads, self-aligning rockers).

You may only want/need to cut down on the advance a little because you will probably be a little lean. What year is your car, injectors size, and fuel pump you running?

Hal

 

'94 Z stock injectors..

Don't rr's and headers create false knock with the stock KM? Or is that only the SA rr's.

I've got a 255lph sitting in the garage that I'll install this weekend. I just finished the hotcam yesterday and tuned it this evening.

I went for a jaunt this evening up to 90mph shifting around 5200-5500 and the tuning seemed to be pretty good. I just noticed it's detecting a little knock, but it's done that way back when all I had was the headers and rr's though. It did it regardless of the tune too. It's not going lean either so I don't know.

I guess I'll just try pulling some timing in the spots it showed up or run higher octane, but if it's still there and definately false, what's the best plan of action?

 

Do you see the knock just when you first give it full throttle? Thats when I see it, nothing later. My OBD2 pcm does not show knock even with the exact same setup (stock tuned obd1 AND the same knock sensor). I took out timing and its still there so its just does it.

Of course take out timing and great gas first but if its still there just turn down the Knock Fast Attack Rate (you can take the multiplier under 1 like .9 or less) or reduce the Max Knock Retard per MAP.

Hal

 

yes you can just desensitize it completely by using the

max knock vs rpm..table
" map..table
burst knock retardvs coolant temp.

turn all of those to 0 and your good.

 

Vince,

I actually have an LT4 knock "sitting next to me"...I know you said that it wasn't necessary to install one since you said you programmed the knock out...will it be worth it at all to install it or should I just sell it to Mike?

 

The last couple of times I've logged my car I've noticed that I had a ton of retard on initial tip in and was seeing knock retard almost all the way through a wot pass in any gear. Tried file after file of more fuel and less timing and still could not get rid of any of it. Then I rememberd that I gave a friend my LT4 knock module as he was seeing quite a bit of false knock due to his rockers and I never got another one for myself.
Well, got it saturday and did a little tuning today. I can go wot in 4th gear at 2000rpm and run it all the way up to 5800 and not get any knock anymore. Not even the mystery knock I was getting at 4400rpm on every run. The only time I'm seeing any sort of knock retard is on a shift as soon as I get back in the gas.
Thing is I have the burst knock retard completely off so I guess that's not the problem. Got any ideas on how to tune this out?

Also, have any of you successfully gotten the pcm to bring the timing back in that it has removed quicker than what the stock setting does?
Of course I know that I need to go into the Knock Retard Recovery Rate table but what do I need to change? It says % Retard Removed / 8 Cam Pulses. WTF?
So the higher the number the quicker it puts timing back? Or the lower the number?

 

If I remember correctly, the higher the number, the quicker the knock is removed. For every 8 cam pulses, that percentage of knock is removed, assuming no further knock is detected.

 

That's what I figured. Just though I'd ask before I started screwing with it.