The first time I ran my car a few months ago, I ran a 14.81 @92.1 with just a cat-back exhaust. Today, I ran my car again with the mods in the sig and ran only a 14.94@91.09. My r/t was .571, 60' 2.248. The weather was warm and a little humid, but shoudn't I still be faster? Thanks for any help.

 

might be time for a tune up.

 

What's your altitude? How warm and humid was it? LT1's do NOT like hot/humid weather. Just off what you've said, I concur with the above. Tune up time. Those times are off by about .6 or so and about 8 mph. You should be trapping right at about 99 or so.

 

Something is definitly amiss.

Get a tuneup and go from there.

 

For the tune up, what should I have replaced besides plugs and wires? I haven't had the car very long, so I'm not sure as to what things should be replaced. My car has 74,000 miles on it. Oh yeah...the temperature was probably around 70 or so, but the humidity was high. My friend told me that a stock LT1 ran a 14.7. I still know mine should be faster despite the conditions with the few mods it has. Thanks again for the help.

 

No, a stock A4 LT1 should run in the low 14's to high 13's. 14.7 is waaaayyyyy too slow for an LT1 car. Should also be around 99 mph, like what was said earlier. Do the usual tune-up things (oil change, air and fuel filters, plugs, wires, ect.), then go from there.

 

I ran a best of 14.99 with a 74,000 mile stock Z but I think I have some tuneup issues that I'm trying to correct. I had the infamous high RPM miss (that I hope is going to be corrected when I finish the plugs n wires tonight) and the air filter was caked with dirt. Air filter looked like tar was applied to it. Also low air pressure in the tires and 87 octane gas along with the upper 80's temp. Car was running hot etc......


Anyhow, hopefully all of this will be corrected with the tuneup.

 

I have an LS1 and the best I've done is 14.5@97 and second best is 14.6@100.6! but this is at like 3500 elevation, sometimes corrected to much more (I heard the night I hit 14.5 it was 4700) This sucks because I know my car is supposed to be at least a full second faster.