So,

New headers, plugs, wires, cat back, Volant cold air.....

everything was fine until the headers. problem was the older plugs and wires, Installed new plugs and wires runs like a top... just slow.

Went to the track, 17.3 stock, 18.6 modified by my mph is off by only 2 at the 1/4.... I figured it was probably heat, 98* that day.... Took it home didnt drive for 5 -6 days... still is slow.

Whats strange is this....

Normal driving..... some times when you leave the traffic light it feel like it has an extra 100 hp... shifts firm and makes u think, man this peppy for a boat.... stop at the next light and i hardley wants to go at all.. shift are sloppy and it feels like you 15,000 lbs behind you.... Does this all day long but not in sequence.... some times you might stop 5 times... and it run good... other times you just want to run into a tree....

Satruday i took the volant off, mass air out, and cleaned it with the mass air cleaner that Advance sales... Put it all back together then pulled all the ecu fuses ( no clue if that doese anything or not, it use to on my toyota) Put it all back together, Started it up and it was louder, actully has a cam sound to it sounds real nice... the noise difference was even noticable by wife and 4 year old daughter. Shifts are nice, power if half way back....

Well for the last 3 day, about 500 miles it has been doing its back to doing the reandom power and shifts.... and my idel seem to come and go... its like the car has a freaking volume control on the exhaust!

So after all that i typed above could this be caused by a bad mass air,

If so, should i replace that or switch to speed density, and or is there a kit to do that on a 8100?

Oh also if your hammering it (unloaded) some times it runs thew the gears slowley, but recentley it has been shifting, rpms fall to 3400-3500 rpms and jsut seem to stay there... sounds like a freaking stall in a muscle car... the spedo goes up "slowley" but the tach just stops.... then revves on to red line, shifts, and does it in 3d every now and then... other times it doesnt do it and it pushes in the seat torque wise the same as my friends sts-ed camaro which is 500 lbtq...

 

Actually you're on the right track, I've been having the same issues with my 5.3. If it meets a MAF fail condition it will go into SD mode, wich will effect the shifting, performance, idle etc. That's prob. why it sounded like it had a cam cuz it was idling lower(mine sounds cammed at 550rpm),are you getting a dtc? if so I'd be willing to bet if you clear it it will run like a top.
I think you need to do some logging and find out what's causing the problem. Are you sure you don't have a leak somewhere? intake? headers? near the O2 sensors?I'd check for leaks, check your plug gaps, plug connections, MAF connections and do some logging then go from there.
Someone else may have some recommendations as well, but spitting image of how my truck's been acting, mine is due to some tuning issues.

 

I know there are not leaks in the exhaust and cold air intake, Checked all that... the plug wires are on correctley. I havent checked the gap on the plugs, i just assumed the shop put them in at the correct gap.

I have been told the actual intake its self has been known to have issues with leaking, but allen ( chevy mechanic ) said on the 8.1 it blows oil out then intake if there is a leak.

I have a friend that has a 8.1L truck of the same year. I might see if i can rob his mass air and swap them... If he starts having problems and mine go away then that should fix it. He also has Hp tuners so ill see if he can show me how to log stuff.

 

that would be my next step, eliminate or prove the MAF as the problem.