VE adjusting

[dk249]

I finally ended up going to a place that had a dyno and they got the ve tables to get the most horsepower. Now trying to get the spark tables right. Found out that I set my initial timing 4 degrees after instead of before. I'm having a problem with getting any knock no matter how advanced I make it?? Checked the knock sensor and it works. I tapped the block next to the sensor and read knock counts for each tap that I made. I have aluminum heads, so I thought maybe that was muffling a knock on this 454? By Advancing so much there was a huge difference in how bad it ran. Any ideas?

Can't hear any knocking as well.

[steveo]

is your knock filter or module appropriate for a 454?
aluminum heads are usually noisier so usually more false knock from valvetrain etc but engine acoustics are a complex thing to say the least

[dk249]

The 454 is the original engine for the truck with org PCM. Doesn't look like any filter or module between sensor and PCM from diagram and when I tested the wire with a ohm tester, it tested good. Is there a filter or module in the PCM? I have tried two different knock sensors, the org and a new delphi. Sending the delphi back for a replacement to see if it was bad or not as sensitive as it should be. Does anybody make a more sensitive knock sensor? There is only two for this motor. One for automatic trans and one for manual. I'm thinking the manual one would be even less sensitive?

[steveo]

maybe there's no knock
were you monitoring the knock count or knock retard
the knock retard may not increase if you are outside the operating range where knock retard occurs
many factory calibrations don't retard spark from knock events when not under load

[dk249]

I have been doing both load and off load at sometimes more than 45deg advanced at 1000 to 3000RPM and 50 or more above that and no counts or retard until I physically knock on the block close to the knock sensor. When I do that I will get counts and retard readings on monitor of up to 8deg which the parameter is set to. And yes maybe there's no knock, but how can that be possible?

[dk249]

I have the new knock sensor and it is a little more sensitive. Did a test run and no knock counts Set the spark table to the same as last post and no knock but backfire through the carb so I quickly dropped timing back. The only time I can get the knock sensor to respond is when in park and rev it to 4000 rpm. So what is my next step in getting timing right for this cam, heads, TBI boarded out and compression increase?

[steveo]

it would be nice to confirm that actual knock causes a knock event. can you give me an example of a timing increase vs map vs rpm you have implemented to try to generate knock

hopefully someone with high altitude experience can chime in here. your cylinder pressures are much lower than i have ever dealt with.