Black Smoke But No Pings
 

Last month I had a Vortech supercharger installed and things have been running great. The only issue I had was that I had a little detonation under very hard excelleration at higher speeds. If I down shifted from third to second (say to roast your friendly neighborhood F-Body), rpms at 4000 and I punch it, I'd get some detonation, nothing too major, but some. Same situation going from 4th to 3rd. I never got any in 1st gear under any circumstances. I was going to take the car back to the shop I had the sc installed at and they would correct the issue. Prior to doing this I have had a completely new exhaust system installed, X-pipes and high flow single cats on each side, 2.5" all the way back. The speed shop said to do the exhaust system before bringing it back as they'd reprogram the computer for a higher fuel rate now that I've got a better breathing exhaust system and they'd corrrect the pings. However, once the exhaust system was done, I haven't had a single ping under any circumstances and I have not any reprogramming done of the computer, which is great! Only questions is, when I start the car a get a small puff of black smoke and I think I smell a little unburnt fuel. I didn't have this prior to the exhaust work, I think. My questions are 1. Why would the detonation go away after the new exhaust system was done (I'm using the exact same gas stations and premium fuel) and 2. What is now causing the black puff of smoke at start up and is it a critical situation where I need to get the car retuned asap. Sorry for the long story, but any input is appreciated. Thanks!

might need a new ignition system with beter plugs and coil with an amp.... but I'm taking a shot in the dark. either way the guys at the shop said they will fix it, so take it back and tell them to fix it :) really sounds like you are not geting enough of something in the engine, air, fuel or spark..... might need to change the timing too....

Torinalth

Torinalth has a great point. You might need to upgrade to a better ignition system. Also, your car has a returnless fuel delivery system (stock). Alot of people say (and I would have to agree) that returnless fuel systems are bad when using boost. It causes detonation and failures. I would look into:
1. The fuel system..ask around about boost with the returnless system.
2. Ignition (MSD or Crane).
3. Different plugs.
4. Your timing. May need to fine tune.
5. Did you upgrade your fuel injectors and mass air?

Cheers

since you do have a super charger i would recommend at least spark plugs designed for that application and a msd dis 4 wouldn`t hurt either