Cool Air, new Cadillac STS-V times

I have some dyno time scheduled for Saturday, so I wanted to get a current baseline on my 08 Cadillac STS-V.

Racelogic PerformanceBox GPS times:

Speed(mph) Time(s) W/Rollout Dist(f)
10 0.95 0.56 6.34
20 1.64 1.25 21.45
30 2.31 1.92 45.86
40 3.05 2.66 84.29
50 3.94 3.55 143.25
60 4.94 4.55 223.83

New low time today — a 4.55 sec 0-60 mph with rollout, or 4.94 sec w/o rollout.  This was my goal for the V — to get to a solid <5 sec without rollout.  Car had 3/4 tank of fuel and the run not heat soaked.   The STS-V has the Spectre cold air intake and a Corsa axle-back exhaust system.  I weigh 35 lbs more than the standard 160 lbs for the buff magazine journalists who get the great times for car mag tests.    Local fuel is 93 octane E10.  The backup 0-60 run was 4.74/5.13 sec.

The 60′ time was 2.2 sec, which is an improvement from my usual 2.4 sec.  PkAccelG was 0.77G. The 1-2 shift was recorded at 0.4 seconds.

Peak Hp was calculated at 6,371 RPM: [click on the image to zoom, hit back to return]

Peak calculated HP at 6,371 RPM

Calculated HP has steadily run less than expected on this V, but I am not clear why.  It uses the Delivered Torque calculated by the engine at RPM to calculate theoretical HP.  The value is a notional figure and not considered accurate for tuning, but I use it as a relative indicator.  I am also not able to run flat out in 4th gear as on the dyno though.

Same run, peak HP at 65 mph at top of 2nd gear:

Top of 2nd gear at 65 mph

Interesting that boost in 2nd gear was running 10.6 psi vs 8.8 psi at the top of 1st gear.  I do not think this is a tuning issue but may have just been a transient thing.  The boost was trending in the 9s then dips and then peaks at 10.2 psi at the 1-2 shift in the scan.

Due to the low temps, the IAT Advance was actually ADDING timing instead of retarding!

Here is the cold air IAT / IAT2 histogram for the whole test cycle:

No KR anywhere on the run.   PE is commanding AFRs down to 10.5, so that is something to consider.  Safe AFR for a supercharged engine probably up at 11.5 to 11.8 where the engine should make more power.

Atmospheric Conditions:

Atmospheric conditions and effect on HP


2 thoughts on “Cool Air, new Cadillac STS-V times

  1. Just finished my STS-V last week. No bolt ons at all – nothing; just a tune and I finally acquiesced and put it on the Dybojet 248 and made two pulls – both SAE corrected as it was cool out.
    First pull made 384 and the second, almost immediately after, made 379. I don’t remember the torque as this was a lark to me as my speed interest is in the drag car and not the daily driver.
    There was one change made to the car, I pulled the intake ‘silencers’ out and taped the holes shut with good furnace tape and then re-installed them and I removed the heat holding pretty, Caddy engine cover.
    I have no idea as to the benefit from an exhaust or intake as my disposable income goes into the 565″ drag unit.
    Lastly I just got back from a 1200 mile trip to TN and I could not get better or worse than 20.6mpg at pretty much a constant of 80mph just keeping up with traffic and occasional blast well into boost too.
    I remain convinced these are the fastest 268″ units ever made.

  2. Good numbers. These cars love cool air more than anything. I meant to get back on the dyno in the winter but let the days slip by.
    Keep me posted if you decide to add a lower or upper pulley. The upper needs some work on the snout, but I think the way to go may be to purchase a 2nd snout with the appropriate pulley pressed on; then it is just a bolt-on change.

    I am seeing a bit better mpg with the Corsa for 10-12 mile trips but I need to do a long road trip to confirm.

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