Knock at idle after spark plug change

[Aphix]

I just replaced the plugs in my car. I went with the NGK BPR6ES, I'm running 13 psi on a 16g, w/ full intake and exhaust, stock smic. I gapped the plugs to .028 and replaced the old ones, which were like .060! I also cleaned my diy MBC and checked it for cracks in the hoses or other leaks and its fine. Anyways, I put the new plugs in and I drove a few blocks and could hear a real deep sounding knock. It sounded like it was coming from the block and gave the exhaust a "hiccup" sound. I have been reading posts but nothing quite sounds like the symptoms I have.

I am also positive the car wasn't knocking before this.

Any help would be great.

 

[newTSIguy]

I just went from the ngk bpr6es to the ngk br7es and my car seems to like those a little better, I am running 15 psi on a t25, any way my advice would be to throw the old ones back in and see if it still knocks,

 

[Aphix]

I just replaced them with the old ones, the knock and hiccup goes away. I just dont get why the car would like these dirty old plugs with like a .080 gap over the ngk plug?

 

[95tsiemad]

You gap them between .28 and .32 That's proablly why it's dosent like them

 

[iminadaze]

Widen the gap .028 is not needed unless you are getting spark blowout.

 

[Aphix]

So gap them to .030 would be a safe bet?