ok i have about 10.3:1 compression in my ls1 and between 70-80 mph i start getting kr at wot and it doesn't seem to matter if its 17* or 28* it happens at the same speed about everytime don't matter what the temp is and i have some other little knock issues. so my question is i see the tr6 plugs are for fi n20 and high comp applications. so with my heavy *** truck would 10.3:1 be considered high enough compression for tr6's i read where another guy was having similar problems as me and swaped to tr6's and it seemed to fix it. any ideas??

 

I've never thought of plugs when it comes to KR. Not to say it is not an issue. Have you tried running some high octane fuel to see if it is false knock?

 

i run 93 day in and day out. i got rid of some of the kr by raising the burst knock table a little and it got rid of the knock that you don't see but was pulling timing i know this becouse i had the timming set at one thing and was getting that minus the table for how much the burst knock would pull. plus with my mods i just think i'm missing some thing becouse it seems like there should be alot more in there than what it seems to have. can haveing 100 pounds of rim and tire on each corner make a big diffrence. i just think there is some power missing. i raced snake eater yesterday just playing around i had two predetor 50cc quads in my bed and my rancher 350 on my 6x9 trailor and he had his ransher 400 on his homemade trailor behind his yukon and although i did spin comming out of the hole i like didn't leav him that fast at all. any thought.

 

try switching to tr55's and see what happens. Isnt the stock CR of an ls1 10.3 or 10.5:1?

 

no its like 10.1:1 i think and i already have tr55's thats the hotter of the two right? i hope its not 10.3 or 10.5 because that would mean its even higher now lol. i put in the thinnest head gaskets that felpro make in there.i forgot the thickness but they raise compression a little.

 

i'm trying to figure up my compression ratio what would it be with a stock 02 ls1 with the felpro head gaskets at .041"

 

Ya I wasnt too sure, I just saw over on tech that it was 10.1-10.5:1.

 

any body else?

 

burst knock is PCM-anticipated KR, not actual KR. The PCM senses an influx of air and assumes KR is close behind, so it uses the burst kr tables to reduce timing and kill the KR before it happens.

Plugs will help if you are actually seeing detonation, but will not help get rid of burst knock.

It may also be a throttle transient causing some KR in that range (for instance if you are crossing one of the trim boundaries -- especially the 4k rpm limit and the PCM is switching fueling algorithms).

I don't think you need plugs yet. First, dump some octane in the tank and see if you get the same knock at the same speed. If you do, chances are you are trying to correct programming with spark plugs and it won't work (in which case work on your burst knock settings -- they are pretty agressive from the factory as I recall). If the knock goes away, try a colder set of plugs (TR6s would be good). Since a pretty radical timing change doesn't affect the kr, I doubt it is real KR.

 

i raised the pe a little at at time on up the scale and ran today and it was better i already changed the burst knock and was getting it still starting about 70mph but after a few runs it stoped doing it all together but with the same 28* of timming. i'll post my logs later. gotta go do a remote start for a lady.