I have a 06 electraglide with 203 cams, I also had the bike dynoed with a PCIII awhile back but the bike runs stronger on the stage1 download than it does on the PCIII, the only problem with this is I get some spark knock, actually quiet a bit since I put in the NGK irrouidum plugs, was wondering if a plug swap back might help the problem.

 

Are they the correct heat range and/or application? That should be the only way a spark plug can affect spark knock.

 

Well it's what the guy's said that Speed's Performance was running but at that thought, he was the one who dynoed the bike twice and I told him that the Stage1 was stronger ever time, I think I will swap back th the autolite plugs I had in before the swap for a ride today just to see if it makes a difference.

 

I changed plugs and rode about 170 miles and it's still doing it, doesn't seem as bad but it's still there, man it makes me sick to think I paid good money to have it dynoed but I'm going to have to get it dynoed again, [:@], you can bet your bottom dollar it's not going to be the same person this time.

 

Spark knocking is wither a function of being lean, or avance is not right on a basically stock bike. Compresion increases will cause it also as will a cam with a lot of duration.

In your case, the 203 cams are a relatively mild cam without a lot of duration or overlap and if properly installed and tuned, should not cause spark knock. Maybe if you talk to the guy that did the tune and let him know the problem, he might retune for free. That build should not knock.

BTW, I am running a 244 duration, .650 lift cam and dont have any spark knock. You can tune it out most times, only sometimes to do so you also lose some of the available performance. I am doing the tuning myself with a DTT II tuner.

 

Dalton I appreciate the response, and you are correct, talked to the tuner at the HD shop where I will be getting it redynoed at, he asked what kind of exhaust I had, I have tru duals and he said that's why your getting spark knock, the rear cylinder is to lean, when I hook up the PCIII it adds some fuel to the mix, thus no knock, even though the tune is not right it's better in that area than just the download, so I will hook up the PC for now until I can get that baby redynoed, thanks for the reply.