ZTwentyAteU

iTrader: (12)

Heres my problem. The car runs great on the street, but when it comes to track time(every weekend), it 60fts like crap. I launch it at about 3k on street tires, and it falls on its face every time. Lets not even talk about drag radials. I'm not spinnng, not even on street tires. I CAN make it spin, but then it falls on its face and then has to come out of the slump. I can get it to run 2.0 60s, but even thats with it falling hard. I know its making the HP, because it runs 86-87mph. On a 100 shot, I was running 7.90@94 mph. Thats activating nitrous at 2400, and it has already fallen on its face by then and is coming out of the slump. It didnt do this until I put the longtubes on. I can't figure it out, it has a good HP tune in it, and i've tried screwing with it a lot but cant get the low end bog outta it. Any ideas? I have a whole 3.73'd rear going in, and that MIGHT help, but who knows

Demon Of Dreams

iTrader: (3)

just a few thoughts.

18's aren't the best for launching, they're doable but normally don't have the largest of sidewalls on them...
You're running with sportlines, also not a great thing for launching
those two things right there don't help any, power or not.


LT's without a tune or improper tune cause you to run richer at the lower end, and they also take some of the lower end torque away ... if you're doing your own tuning, I would look there first to see what you're running...

then start looking elsewhere

other than that... I'm going to ask a really ******* stupid question...

are you taking your traction control off?

Mudvayne

iTrader: (1)

Not to insult but you check your plugs?
Also are any of your spark plug wire boots touching the headers?

ZTwentyAteU

iTrader: (12)

I don't have traction control....my car was tuned with the help of a pro tuner, and it does not matter about the 18s, traction is not the issue. Plus I just sold them and got some zr1s. Like I stated, if I put drag radials on I have to come off the line at 5 grand or more and it still will fall hard. And i've had great success with sportlines...I don't see why everyone bashes them, i've had 5 sets! And i've gone low 11s on them

ZTwentyAteU

iTrader: (12)

I do check my plugs regulary, as per I run Nitrous. So the plugs are new and the MSD wires don't touch

Demon Of Dreams

iTrader: (3)

still might want to look at the tune then.
one would assume you'd retune after the LT's... so if it's not the tune, it's something else.
LT's may not pick up a whole lot of torque but they won't ever really kill ability to launch properly unless there is something wrong with the tune.

Even untuned after my LT install I've never once had a problem

jimmyblue

iTrader: (11)

LTs are prone to bang when the engine rolls on its mounts and
this can give you a lot of knock retard, which feels like you have
described. Get a scan tool on there and you can see if it's that,
or a mixture problem (stompiong the throttle puts you into a
speed density mode temporarily and if you're just getting by on
the MAF "covering up" a fundamental mistune (or, a stale tune
not kept up with the mods) that's also a way to bog (and might
be as responsible for real KR as banging can be for false KR).

ZTwentyAteU

iTrader: (12)

Ok, today I have gone in and logged, and found a little knock retard. I've been desensitizing for a while, now I have pretty much elimenated that part, which wasnt even doing anything below 4000rpm.
Then I tweaked PE table, and PE delay set at 2500.
I'm going to the track tonight and logging more, but the PE Delay seemed to help more than anything.
thanks for input

Full-Force

iTrader: (11)

Its not uncommon to bog on stock gears with a 6 speed if you hook. My car used to bog like yours launching at 5000 on nitto drag radials on a sticky track. Its all about the 2.66 1st gear. I wouldnt waste time on 3.73 with a 6 speed either.

Get you some gears before you do anything else.

ZTwentyAteU

iTrader: (12)

I guess the tuning did the trick-new best last night NO nitrous was 8.28@88mph
No bog and no BS. This thing is making some HP to run 88mph. It ran that all night