B8 S4 headers bank or bust?

B8 S4
#181

or just do some pulls on a private road somewhere

#182

or this but I would prefer to see a full 1/4 and the various points… Looks like Pacific raceways is open this Sunday… Man do they charge alot to tnt out there… OUCH!

#183

Maybe that was it. I changed from my stock 18’s to 19’ BBS CHR

Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
245/40-18 3.9in 12.9in 25.7in 80.8in 784 0.0%
255/35-19 3.5in 13.0in 26.0in 81.8in 775 1.2%

#184

http://www.dragtimes.com/gear-ratio-calculator-mph-speed.php?tire_width=&tire_aspect=&wheel_diam=&tire_diam=26.0&axle_ratio=3.875&redline=7000&gear1=3.692&gear2=2.150&gear3=1.406&gear4=1.025&gear5=.787&gear6=.625&gear7=.519&gear8=&calc_button=Calculate

#185

That would have hurt MPH in each gear (and hurt gearing).

Anyway, you clarified above that it was an RPM thing (although the headers wouldn’t adjust shift RPM/rev limiter. Maybe you just mixed up the recollection of the speeds at which you shifted since you were breaking the law by a factor of 200% lol.

Are you out in Seattle? You should do 2 things

  1. see Alice in Chains when they play a warm up gig somewhere around there before their spring/summer tour
  2. race the AMD supercharged RS4 belonging to member ‘PERrs4’ on this site. It looks pretty quick but we’ve only seen it vs. a stock RS4 (not exactly a great comparo lol).
#186

how much? Ours is like $30 or $40 on the weekend. It’s $20 on Wed or Fri but that’s only a few hours.

That’s normal I think. Your $2 test and tune is the exception rather than the rule lol.

#187

$40… It’s $12 at Thompson not $2 :stuck_out_tongue: LOL!

#188

http://farm9.staticflickr.com/8240/8614624508_d05de6c9db_b.jpg

#189

Too bad we don’t live in England, they have a DSG flash available:
http://www.amdtuning.com/product.details.cfm?ProductID=17369&VariantID=1243&ReferenceID=169440

#190

Will have one here soon…

#191

You guys do realize the 2013 has longer gears, right?

http://www.youtube.com/watch?v=2mNq95lRqQI

120-ish in 4th at the new, lower redline

#192

If he sold a B8 and bought a B8.5 what you said would matter.

From the looks of it though he didn’t. He said he went from topping out at 113 to topping out 4th at 120, as a result of the ‘upgraded power’. That makes no sense in itself.

#193

Has APR talked about their DSG tune yet? Or just at the dealer conference?

#194

Maybe are misunderstanding my post. Mind you this all on a dyno’s speedomoter calculation, so that could be the problem.

I said the DSG would shift 4 --> 5 at 114mph in stock clothes. After the tune, I was doing 120 mph before the shortshift. I graphed the two different 4th gear pulls to show this…

#195

Looking at the graph the cutoff RPM is nearly the same. Without a gear change, running the RPMs further out or drastically changing your tire size as the few have put it, it is improbable that you are going faster prior to your shift point. Even if you added 100hp to your setup you will still change gears at the same mph given the same RPM, you’d just get there faster.

Your change in tire size is only 1.2% difference which would give you a change of ~1.4 mph. I believe what you are seeing may be related to the program you’re referencing.

#196

My buddy and I are planning on hitting PR on Sunday for their TNT session. This will be my first official trip to see some strippers. What is the protocol on setting up the cars? Any tips? (besides removing the spare tire)

-Tire Pressure?
-Timing tips?
-1/4 tank

They sell Sunoco race fuels, I will plan on doing some 100 file pulls.

#197

Good stuff dlo… that is true. Gears and shift rpm speed is the same time passed is what changes…hp 8s a calulation of tq/time

#198

We have a quarter mile tips thread here somewhere. Find it and give it a good read.

Pay particular attention to how you stage the car. Shallow stage every time. Ignore the lights as all you care about is ET or Elapsed Time. The lights and Reaction Time don’t count for your quarter mile time at a test and tune…just when bracket racing.

Otherwise, read that thread. I believe primetime posted in it, and he has more passes in a B8 S4 than anyone on the planet.

#199

From the other site:

[QUOTE=dparm;8120455]There’s such a thing as a thrust curve, which I wrote about in the B6/B7 S4 forum. It relates gearing with powerband location and size.

Thrust = (Engine Torque x Gear Reduction x Final Drive Reduction) / (Wheel Diameter / 2)

You graph thrust on the Y-axis and speed on the X-axis. What you’re looking for is how well the lines come close to meeting each other. It’s an effective way of showing how well the gears are setup for the car’s powerband size (width) and location (RPM range). Also helps you determine optimal shift points.

I generated thrust curves for the B8 and B8.5 S4. This is a stock motor with 25% drivetrain loss on the stock 19" wheels/tires.

B8 S tronic thrust curves:

http://img.photobucket.com/albums/v80/TheGSRGuy/2011_audi_s4/b8-stock-thrust.png

B8.5 S tronic thrust curves:

http://img.photobucket.com/albums/v80/TheGSRGuy/2011_audi_s4/b85-stock-thrust.png

A few comments about these curves:

For the 1-2 shift, go to redline on both cars.
For the 2-3 shift, go to redline on both cars.
For the 3-4 shift, short shift on the B8. Redline the B8.5.

The 1-2 shift is always violent because of that gap in the curves – there’s a big change in the amount of thrust we generate.

I actually did one for the Stasis tune (B8 only, of course). We obviously generate more thrust in every gear but the S tronic gearing is not optimal for the new powerband location and size, as evidenced by the gaps between the curves. That means you would want to redline every gear.

http://img.photobucket.com/albums/v80/TheGSRGuy/2011_audi_s4/b8-stasis-thrust.png

So what’s the tl;dr here? Yes, the B8.5 is not geared optimally to take advantage of its power. No street car is, but the B8 is a hair better.
[/quote]

#200

Saki/Anyone experienced:

What exactly does it mean to “shallow stage?”