I have no actual data or proof, however its noticeably easier to break my winters (dunlop 3D)loose than my summers (michilin pss). Also its not like I ever warm up my tires. If clochner can hook up as well as he did with his summers then he should run a better time with lighter wheels, and small rotating diameter.
Clochner, My .02 fwiw… The updated tune will help you much more this time of the year than in the summer as you will see less bypass from the colder IAT’s… IMO I didn’t see any significant changes in timing if any at all, based on logging while making passes with the beta stage II I ran for quite a while… When I went 12.06 stage I, I had a decent amount of bypass and with a revised tune I think I would have went 11.9x stage I but that is obviously speculation… When I went from beta 100 to v2 100 I didn’t see much if any change but Arin told me there were indeed some small tweaks but again nothing I could tell from logging… I did notice an increase in timing from the 100 tune to the 104 tune that I have…
As for the winter tires if they spin just lower the pressure and they will hook…
Try some runs with and w/o LC as I don’t think it helps but that is just based on what I have seen others post since I don’t have it I can’t really test… Looking forward to your results…
Thnx for the advice, Ron. I’m hoping the weather will cooperate to get the most out of version 2. And I will definitely do runs with and w/o LC. I really want to end this debate about the efficacy of LC (at least w/ respect to my car).
^^^your car did pretty well with launch control didn’t it?
Reality is that it’s not adaptive, learning launch control. it will work in some traction situations and it won’t work in others. Sometimes you’ll get more traction than the program is expecting and it will bog. Sometimes you will get less traction and it should see some chirp. Other times it will be just right and will hook as well as any other method. Launch control is not ‘best launch’. It’s launch control…in other words, it provides a controlled, foolproof performance launch that will get you moving nicely and won’t see you losing out or screwing up.
It’s not always better. It’s not always worse either.
Your previous time was on pump gas…right? It shows as both 93 and 100 on the spreadsheet, milltek and APR intake. There’s maybe a tenth improvement to make, maybe, v1 to v2 gains are minimal.
When it comes down to it, I didn’t see a huge gain from v1 to v2, traps are the same, it’s just that my 12.26 run on v2 short-shifted 1-2 all night so I only got 5000 rpm out of first gear. I am pretty sure (and so are others) that the short-shift is a traction issue. That 12.26 v1 night I had basically bald OEM P-zeros, which were more-or-less hard as hockey pucks. I had new tires and v2 and did the 12.08. I’ve been within a few hundredths after that, it’s pretty consistent.
I think the only guy who saw success with the factory LC was Fonzie. From what I can see, it has a much milder clutch engagement (possibly softer throttle response too) than just stomping on the gas. Again, like prime, I don’t have it (2010 here).
Do take logs if you go…it’s worth it.
Clochner,
I’m going to go against the grain on this one.
I firmly believe that LC would, scratch that, could make a difference with 1/4 ET vs PT’s method. It really comes down to traction.
There are a number of factors that will affect your traction off the line:
- track temperature
- track prep
- tire temperature
- tire condition
- tire pressure
- Launch RPM or TQ off the line
Though I’m sure there are more I’m going to stick with the basics above for our purposes. Now going through the above list a number of these variables are, for the most part, out of your control:
- track temperature (weather dependent)
- track conditions (track dependent)
- LC launch RPM (Audi or APR dependent)
Now, the good news is that there are still variables that are of your control like:
- tire condition
- tire temperature
- tire pressure (This one is key)
Tire condition - not only refers to having good tread on your tires but also to ensure that the tread is clear of rocks, sand, dust, etc. To ensure good tire condition I check my tread levels but also I do a mini burnout (Jspazz method) each time in the staging lane before I stage. This removes rocks, gravel, etc off the tires nicely (side-note, since I’ve started to do mini burnouts I have NOT had the 1-2 shift hang-up that had been plaguing my car in the previous outings).
Tire temperature - I use a combination of hot lapping and mini burnouts (mentioned earlier) to get the tires nice and warm before I make a serious pass.
Finally, tire pressure - This one, in my mind, is going to be KEY to getting your LC to work effectively. You’re going to need to adjust pressure throughout the day for all four tires based on temperature, track conditions, and tire temperature. I’d start with a tire pressure of say 33psi fronts and 28psi rears. Do a few launches and adjust from there. You’re probably going to go down to 28psi fronts and 23-24psi rears but that’s just a guess.
I think looking at previous data regarding LC vs. non-LC is misleading. I’m not sure many B8 S4 owners are actually drag strip vets and they may not understand the importance of tire condition not to mention the macho factor (we all get trapped in on occasion) of trying to beat the guy beside you and at the same time trying to get your LC to work without overheat.
Anyway, this is just my $0.02 on the matter… Give it a try and let us know how you do… Good Luck!
Wouldn’t it be great if you could have a DSG tune with launch control that you can dial in on your own?
I saw that on a Boss coyote tune…hey we’re asking too much…just give us the last 200 rpm
Nice post bear. Those are low pressures, is that what you went to last year? I think I’ve gone 30/26 maybe, hahaha Voltron went to 17 in his ctsv. It doesn’t affect the trap as much as people think, maybe a few tenths mph…low pro XL rated sidewalls are quite stiff.
Well you mentioned APR working on one in another thread… can you elaborate?
Just saying it would be interesting. On the JHM Launch Assist development I found that it worked great sometimes and just OK other times. All depending on the dozens of variables outlined by 81bear.
p.s. speaking of bears…baldsauce
Hey we’re all headed there one day
Some faster than others… 
Yet my 90 year old grandfather has a full head of hair, I just don’t get it…
low testosterone vs. high testosterone.
and bad hair products for our generation that dehydrate and kill our hair.
Yes. I believe that stock and even APR Stage I it produced my best times. Though I’d have to double-check. It was also just a pretty cool feature before APR’s original stage II tune tamed it down to the point that it wasn’t even worth trying any more. My 12.45 time was without LC, and yes, Jspazz, it was on pump gas (93).
81bear - good analysis. I tend to agree that LC can help ET, though I am definitely not a drag strip vet. I’ll keep an eye on tire pressure when I head out to the strip. I can tell you that my tire pressure on previous visits to the track were not nearly that low. I usually keep them around 39 . . .
Not necessarily. This stuff has been proven to work:
http://i1098.photobucket.com/albums/g368/kobe11mvp/propecia.jpg
How do you know that’s out of your control?
cus he doesnt have a jhm LC box haha
Well because I/we don’t have the ability to reprogram the TCU to allow for LC RPM launch selection. I would hope that if APR is seriously looking into offering a TCU flash that they would include that type of functionality.
No worries man… I’m by no means a drag strip vet either.! Lol!
Your tire pressure may have been spot-on for the conditions you where in… Did you notice a lot of wheel spin? did your transmission delay on the 1-2 shift? Again, these are my own estimates based on my experience with my car at TMP in close to freezing conditions.
^^^I can comfortably say that you hvae more passes on your car than any other B8 S4 owner other than primetime. In fact, probably more than 99.99% of Audi owners.