Awesome glad to see ya still out there ripping it!
First things first, traction control always off, no matter what and twice on sunday. It's not real traction control like the fancy bmw's and porshe's. It just kills a bunch of timing when it senses the rear tires are moving faster than the front. Not too mention if you you're really banging the gears and happen the spin the tire for a sec it will kill timing and you'll nose over and lose momentum. Use your right foot for traction
Launching these cars on street tires is a tricky ordeal. But it's actually easier to launch with the stock clutch than a stage 2 or 3 single disc after market clutches. The reason is you can really slip it and keep the rpm up without blowing the tires off. It's a fine balance but you can do it. Once I got my Monster stage 2 clutch i had to launch at a higher rpm because it doesn't want to slip. It starts to grab and just clamps down and goes. That's why I switched to drage radials.
Here's a couple pointers for street tires and stock clutch.
Before you head to the track, change your clutch fluid. Get a turkey baster and suck the old stuff out of the resevoir. Wipe the inside with a cloth. Fill it up with new DOT 4 brake fluid. Pump the clutch 50-100times to ensure any air is pumped out. Do it again. If the fluid is still dirty do it again. You want the absolute cleanest fluid if you're going to be beating on your stock clutch.
Take the spare, jack, ect out of the trunk, remove the heavy skid plate, and you can easily pop the back seat out. GTO spare's as front runner's is a cheap way to pick up a tenth. With more power it would gain more.
Let the car cool down before running. The stock computer tune pulls a bunch of timing as Ambient Intake Temps rise from heat soak. You could be in line idiling with the a/c on, get to the front to run and you're iat's are 140deg. Stock computer pulls 9degrees of timing and you wonder why you ran a 14 lol.
Lower your rear tire pressure down to 28psi.
Go around the water and just do a quick first gear burnout, say pop the clutch at 3/4K hammer down for a sec and let off. You just want to knock the dirt off the tires. If you do a big john force burnout on your steel belted radial street tire they will become greasy and spin easier.
I like to get up to the line first. This give me more time to get my feet right. I light one bulb and slowly roll into the next and really stab the brake hard to set the car. Then left foot on clutch. Right foot on gas to about 2700-3000rpm. Then pull your left foot up just enough until you feel the car about to move. You want to be right at the cusp of the threshold area of the clutch. As the third light turns on slowly pull your foot up into the threshold area. Don't just dump it. As soon as the car starts to move push the gas the rest of the way to the floor. This will cause the clutch to slip and keep you high enough in the RPM from bogging but is also soft enough on the initial hit not to blow your street tires off. The rate at which you release the clutch the rest of the away is dependent on traction.
The last thing I do to get my times down low with stock power is no-lift shift. If you don't feel comfortable with that just make sure you're shifting at 6400 and as fast as you can do it. These gear boxes are fantastic even in stock form. They can handle speed shifting and no-lift shifting as long as you can do it cleanly.
Here's some examples.
This was the weekend after I bought it. Bone stock down to the paper air filter and stock 17" tires. Nice slip of the clutch and I'm away, power shifting to a 13.0 @ 109
Here's another run bone stock on street tires. 13.2 Watch when I pull up to the line you'll see me balance the clutch to the engagement point. When I launch you can see what I was talking about as I lift the clutch into the threshold while giving it the beans as the clutch comes the rest of the way up. It all happens really quick. This is with no power shifting. Just normal quick/speed shifting.
One more on street tires and stock clutch but with a vararam cold air intake. 13.0
Hope some of that helps. Really what helped me was seat time. Just getting out there and practicing.
What times are you running now?