Can you try different coil packs? In my experience, some handle boost better than others...

 

I don't have any other coil packs.

 

What valve spring are you running?

 

OEM valve springs.

 

Holty was having misfire issues under load that sounded like your symptoms, he ended up finding weak valve springs were causing it. Stock springs are reliable but weak, they were not designed for boost either as they have fairly low pressure. His were not stock but the symptoms are similar. Just food for thought.

 

I know the 1218 springs wouldn't be the best option, but would they resolve my issues if my problem was in fact the valve springs?

 

1218s would work fine for up to 20 psi, even an ls6 spring is known to hold up to 15 psi without problems (I wouldnt advise the ls6 tho)

 

Okay guys, listened to your advice and swapped in some PAC 1518's. Didn't help at all.

Anything else?

The problem seems to be completely load related. ~45 mph drop to first at wot is solid as hell until it shifts to second (starts misfiring). Also from a dig first will do it.

 

I didn't see if you said it, but what gap did you use on your plugs? I went from .032 to .028 cause I was having the same problem when I went from 7lbs to 10lbs. I was running a tr6 also. Have you monitored the fuel pressure at the rail during this wot run? Also what fuel pump are you running? There are so many factors that can play a role here, If you hadn't changed springs I would have also added valve float to the list lol. Def sounds like it could be a fuel issue, but if your wideband is accurate then it would be a spark issue. Swap some plug wires out with a friends truck to test that(instead of throwing new parts at it) also coil packs. log the pass and keep an eye on knock sensors on that load, could be detonation from bad gas..... post up a log and most of these guys can help ya more than me lol.

 

The plugs are now br7efs gapped around .030. Fuel pressure at the rail is solid.