JonCR96Z

iTrader: (33)

DA is density altitude. It's calculated correction factor using elevation, temp, dew point (humidity) and barometric pressure to figure a common air density as compared to sea level. There are a few sites that have DA calculators and even ET correction calculators.

This will kinda give you an idea, though the 2 tracks that I frequent have different elevations than whats listed on dragtimes. http://www.dragtimes.com/da-density-...calculator.php

On to the mods.

STB and aftermarket panhards aren't needed for drag racing there. If you road race, well you should have bought a manual. If you don't road race it's just extra weight and you shouldn't waste the money. If you've already got them, sell them to a buddy. If you wanted to get any more suspension stuff it should be a torque arm.

Pulley and LS6 intake, obvisouly both are good mods for the money. On stock cars both are known to give around 10 rwhp. So roughly worth a tenth each at the track.

Stall is the way to go. It should be done first. If you don't have the money right now, then don't buy that other stuff and save up til you can get one. Don't be affraid to go bigger than 3200. 3600 and up are really popular, and most complain that they didn't get enough after they drive it. That said you can pick up a good used smaller stall cheap in the Parts Classifieds. Depending on the stall you could gain any where from .5 to 1 second in the 1/4 (with good tires of course).

LTs are a good mod, but have been known to hurt ETs on a stock stalled A4. I wouldn't get these until you have the stall.

LS6 heads are good, and if you can get them cheap they're great. These will go a lot farther with a good cam. My bolt-on LS6 CTSV made 402rwhp/387rwtq on the same dyno that says my TA has 313 rwhp. LS6 heads with a thin head gasket (for more compression and better quench) should easily get you a solid 20+ rwhp, and are worth even more with supporting mods.

Jon

JeaneGrae

iTrader: (7)

So for example my home state is North Carolina and is 650 ft above sea level and i am now in North Dakota which is roughly 1500 ft above sea level. How much of a difference would this make in terms of et at each track?

JonCR96Z

iTrader: (33)

Well if you're in NC and at 650', I'd say find a better track.

Seriously though, Every 1000' of DA is roughly a tenth in the 1/4, though it's not an exact science. Some cars respond different to different things. Assuming identical weather from 1500' to 650' would be about a tenth less in the 650' track.

Not that much difference, but it's always good to keep track of the DA, just for the sake of knowing. For instance, you run 12.95 this weekend, then add a pulley to the car, but the temp dropped 10 degrees on your next trip to the track. So this time you run 12.79, did the pulley help or was it just the weather.

Or say you run a 13.05 in 550' DA, you want to make sure you go back to the track when its 0' DA so you can run 12.9s

JonCR96Z

iTrader: (33)

I always write the temp and the calulated DA on my slips, that way when I look back to compare my old times with new times or someone else's times, I can take that factor right out of the equation.

Kingc8r

iTrader: (21)

Overall good information

JonCR96Z

iTrader: (33)

Well, it's not written in stone, but if you look at a dyno graph if a header install on a stock internal car you might see a slight drop in power in the lower RPM range. And most (maybe even yourself) will definitely say that it doesn't fell as responsive down low, but screams up top.

Well with that idea, a good ET at the track is determined in the first 60'. And in most cars you're not even half way through first gear at the 60' mark. For a stock stalled A4 that would mean that you were at 3000rpm or less. Right where the LTs are hurting your power. Though on the the big end you'll almost always have a MPH gain.

If you look at a A4 w/ stock stall and headers they don't have as good a 60' as a manifold car.

With a stall on the other hand, well it keeps you above that power loss and then some. So your car could gain doubly from a stall. The obvious gains from the stall plus get back what you lost from the headers.

JonCR96Z

iTrader: (33)

What is the average gain through the rpms? I also see that your untuned, did it affect the AFR any?

Kingc8r

iTrader: (21)

I went to a dyno day twice I dyno'd 328hp without the LS6 and PTB. The next tie with the LS6, no PTB and I put down 332. Weather was similar. I know it's not a true showing but still....

I just noticed that's only 4 HP lol....it did pick up a lot of average HP though

john shea

Yes about three years ago I got a 12.9 on a cold october morning.
I only had the 3.73 gears and bfg dr's,no long tubes or ls6 intake.