I've been using NGK plugs and can't hit the sweet spot. TR5/6 Projected plugs. TR5 gets heavy detonation at high RPM, TR6 gets fouling and slight detonation on hot days. TR6 runs better than TR5 hands down, but I'm running a .035" gap due to compression and HP output (is that right?). Is there some magic number gap or some particular type I should be using?

I should note the fouling issue started when I went to a 160*F t-stat (detonation was worse with 180*). I'm guessing the engine is running a bit too cool (dead on 165*F) or I'm just running the wrong plug/gap.

Static compression is 13.89:1
Dynamic compression is 12.57:1
Octane level 93 or higher

 

Sounds like an octane issue, not a plug issue to me.

 

How the hell is your compression at 13.9?
Alos past 11.5 is race gas territory


13.9 on pump should have a 7 or 8 series

 

Yea I was about to say you need a 7 plug in there at minimum with that high of comrpession. Try closing the gap down to 0.028-0.030. What fuel are you using?

 

Also the DCR seems too high as well. You need to use cam specs at .005 to calculate DCR, not .050... did you do that right?

 

Ehh...it's not right. I used the incorrect head gasket thickness (.030 is wrong).
SCR: 12.99
DCR: 11.76

Wallace Racing: Dynamic Compression Ratio Calculator

ABDC is 43.8*
Bore is 3.898"
Stroke 3.622"
Rod length 6.125" (I think that's what was put in)
862 heads milled ~.065"
Deck height -.010"
Head Gasket thickness .051"
Flat pistons with valve notches

yes it's a super close fit lol.

Cam card:
http://imageshack.com/a/img905/5862/8Jtj1w.jpg

I am running either a straight E85 (E70 this time of year) or 93 cut with VP110 (ratio dependent on what I feel like spending )

 

Br7 is choice id run

 

41-104 ACDelco iridium that are OE fitment on ZR1, CTS-V et al

inexpensive, too:

 

What about timing advance?

 

$7 a piece inexpensive?