I have a 406 in my 1986 vette and I am looking far an extra 40 RWHP, on of the ways to acheive some of the 40 additional hp that I am looking for is to raise the compression from my current 10 : 1 to 11 : 1.
My question is that at the current 10:1 compression I am experiencing 5 to 6 degrees of knock retard at WOT from 3000 RPM to 5000 RPM with the knock retard eventually disapearing by 5500 RPM, will increasing the compression ratio to 11:1 increase my power output or just cause me more knock retard? I shift at 6200 RPM so I am assuming I will get some more power after 5500 where my knock retard stops but will I get any more power from 3000 to 5000 RPM?

I am running a superram, ZZ-409 cam, 23 degree Trick flow heads 195 CC runners, SRP forged pistons, 31 degrees of spark advance minus knock retard, TPIS 1.75 headers, SLP cold ram air induction, 30 LB injectors.

 

Usually knock like that is because of high cylinder pressures, and you're talking about making it worse. If you want to do that, might want to try every trick in the book if you already havent like taking the sharp edges off of objects in the combustion area, running a tighter quench area, maybe even look at steam manifolding to get some more even temperatures. I'm not even going to suggest swirl though, way too complicated for us normal folks.

Are you making the most power at 31 advance? Some setups dont like a bunch of advance, I dont know if youve tried.

 

Are you running the 32B or the 6E ???? Are you removing the 10K resistor right after the ECM connects with your datalogging software or are you leaving the 10K resistor in the ALDL port in Terminals A & B ??????

 

I am running my quench at .045 and I have tried different timing settings from 31 to 35 degrees and the power is unchanged from 31 to 33 degrees so I leave it at 31 degrees. I have not tried less then 31 degrees, maybe there is something to be gained.

I am also running the 32B program and I have not removed the 10K resister from the ALDL port, I am not really sure where the resister you are describing is located and how it effect my data logging?

 

Do a search for Vader and burst knock. There is a post on the DYI Prom board about this.IIRC the ECM will add 8 degrees of timing with the 10K resistor in place.

 

You can also add fuel or take out timing where the knock occurs.