Power sluggish when.....

[TGed]

Fixed.  Was the gauge.

Second problem on the list.  So I was driving down the road the other day and when you ease into the accelerator it is all peachy creamy.  As soon as you romp on it and 4k'ish rpms is reached it acts as if I hit a rev limiter and will not stop until I let off and ease into it (Where's the fun in that!) .  I almost want to say it's blowing out the spark type feel cause when it does it, black smoke puffs out the back.   
Here's a pic of a couple plugs.  Sorry about the crappy pic.  Let me know if you need a better pic.

[TGed]

Bump

[flybynite]

Your plugs look fine. Try reducing the gap to .030  You may be having some spark knock due to the crappy gas we are forced to buy...   :icon_twisted:       Just a guess tho

[TGed]

I am running AL 103's gapped at about .030 if that helps and tried running 110 just for shatts and giggles.  I might go back to the AC delco plug and keep the .030 then retry pushing it to the limits.

Thanks!

[TGed]

Update!
Changed the plugs back to the stockers but gapped them at .027.  Problem is still there, but not as bad...  Still very noticeable though.
I could possibly get a sound clip of it in action.