I took the car to the track last year and ran 14.29 completely stock.

I added these mods since:

K&N CAI
3" Catted DP
Diablew Tune

I went to the track last night and my fastest pass was 14.45.

I had some wheel spin before, but nothing crazy, and now no matter how light i roll into the throttle I blow the front tires off. I am VERY confident with some DR's I will be in the 13's no problem. I did take the headlight out, but there was no improvement.

So in conclusion, It is slower on the track, and an absolute MONSTER on the street.

are you just flooring it?? Try feathering the throttle, i takes practice to drag a high HP FWD

did your trap speed improve? if so how much?

How different was the weather? I was off 4 tenths last week compared to last October because the da was so much higher. If your spinning the slightest bit, it will slow ya down. Getting off the line is a science with these cars. I usually rev to 2k, then let off brake and slowly ease into it. Once you get use to it, you will get better. I picked up 5 tenths opening my cutout and taking the headlight out, of course that had a little something to do with me just being slow. But there's no reason you should be slower with those mods, unless the weathers bad, or your spinning.

no sure. I cant find my time slips from last year.

its the diablo tune

compare you 60ft times and trap speeds. weather plays a huge role in performance. even with a shitty 60ft your mph should have picked up over last years run by about 1.5 wich is 15whp

I don't have traction problems that bad. Gotta learn to drive it. It would help if we knew 60' times and trap speeds, DOA, etc.

Really?

yes, two reasons i say that.
1. His car got a slower trap meaning he probably lost power.
2. Those cars are weird. They love timing and are a bitch on the dyno. If you dont have a lot of experience specifically tuning ls4s its really hard. Most tuners are afraid to give the engine what it wants...more timing in this case.

It's hard to believe a Lew tuned car would run slower. There is plenty of people here to vouch for that and I will be one of them in a few weeks. Lew certainly knows what he doing, so saying his speed loss is because of the tune seems farfetched. Lew has tuned enough ls4s to know what they need, I haven't heard a bad thing about his stuff, other than lack of trans support, but that's diablsport, not him. Blame it on something else bud...

He said that he had a little wheel spin before, and now it blows the tires off. If he's blowing the tires off on the line, compared to before, I can guarantee he's losing 4-5 tenths right there.

1. He said he isn't sure about trap speeds, he can't find the slip...
2. Lew is VERY experienced with LS4s...

So Slow

yeah... it's NOT the tune..

wheel spin / loss of traction... weather conditions.. etc...

my custom tune for "these cars" is spot on.. trust me, I've done enough of them.. I know what their quirks are....

hell, DavidGXP gained 39 hp and 23 foot pounds torque with my tune... so don't try to tell me it was the tune

the issue was, wheel spin and/or weather conditions...

It wasn't the tune. Post up your slip.
You should be trapping 100.5-101.5 with the mods you have listed.

The problem is not the tune, or the weather. There is no doubt in my mind that the trap speed is higher in my mind.

The problem is that the car is a HELL of alot more powerful than last year and like I said, no matter what I do I just smoke the tires off the line. Even if I completely let off, and ease back into it, the second I put it to the floor the tires spin again. Its a handfull to say the least.

This isnt really a "why is my car slower" thread, its a holy crap this is so much more powerful i cant hold it on the track, thread.

LOL, thats actually good to hear. Which means don't get DR's or you will fry your trans. I would suggest just letting it idle of the line, lol. You will learn, once I get my tune and take it down the track I will see if i can help ya. I have practically the same exact setup.

I still managed to rip off some 2.0's with the mods in my sig. You guys have shitty track prep or are just to eager too get down the track. Learn how to relax.
It is very important to roll into the throttle. This allows the rear suspension to ease into motion. When the *** end suddenly squats, the front tires become weightless and spin with ease. So.... roll into the throttle to prevent this from happening!
Spring blockers in the rear help by limiting spring travel.

did anyone suggest the state of his tires? maybe traction is not there as oppose to last year.

as well as all that power