Cadillac STS-V shift testing, adjustment 1

[Note the video quality can be adjusted up (click on the gear), and the video can be made full screen.]

Adjustment 1 set: Kept the 1-2 shift at 30 mph, and raised the 2-3 shift to 60 mph across all shift modes.  Raised the absolute fuel cutoff from 6700 rpm to 7000 rpm.  TM adjusted to 25%.

Interestingly, with no change in shift points the 1-2 shift revved to 6600 rpm and hit a new higher calculated hp value.

Shifttest2013-05-11max15

Previously the 2-3 shift was commanded at 58 but happened at 60 mph.  When I moved the commanded mph up to 60 mph it continued to be commanded at 60 mph.  More testing needed there to understand.

I observe that the car is actually slowing down during shifts, perhaps due to engine braking in sport mode.  I will plan to retest with the transmission in drive, which does not use engine braking, to see if that is advantageous.

Update:  I see a source of delay in the 0-60 time — wheelspin after the 1-2 shift is a problem.

Mph Time
0 0
5 0.56
10 0.95
15 1.31
20 1.66
25 1.98
30 2.17
35 2.45
40 3.03
45 3.08
50 3.14
55 3.19
60 5.03
Too much wheel spin after the 1-2 shift at 3 seconds is causing a false mph indicator for a spike to 55 mph after the shift.
The 40-55 run in the middle is due to spinning tires.

run1at15accelerationgraph

Reinstated TM and retested.  Didn’t go WOT early enough in the retest to avoid the transmission shifting early 1-2 (shift commanded at 23 mph).

run1at15accelerationgraph2ReinTM

 

Cadillac STS-V Exact Shift Point Testing

This morning I made 2 runs to determine current shift points during acceleration from a standing start.

I ran the STS-V in “competition mode”; this mode apparently uses “Cruise mode” shifting, which was a surprise to me but means a different table for the transmission logic.

run1gearshift12

Run 1: From 1st gear the shift to 2nd started at 30 mph as programmed. The STS-V reached 6,180 rpm before shifting.  The shift took 0.2 seconds.  The 2-3 Shift started at 60 mph and the STS-V reached 6,310 rpm before shifting.

HP Tuners Information

HP Tuners Information

Run 2: From 1st gear the shift to 2nd started at 31 mph.  The STS-V reached 6,378 rpm before shifting.  The shift too 0.2 seconds.  The 2-3 shift started at 60 mph and the STS-V reached 6,240 rpm before shifting.  The latter is surprising since the logic appears to command the shift at 58 mph and not 60 mph.

With a goal of raising the shift points to 6600-6800 rpm, my plan is to increase the 1-2 shift speed from 30 mph to 31 mph.  In first gear, 140 rpm equates to 0.6 mph.  So a full mph increase in shift speed may raise the shift point by 230 rpm or so from 6,380 to 6,600 rpm. For second gear, 40 rpm is around 0.6 mph, so 200 rpm increase would be 3 mph, or 58 mph up to 61 mph.

I will plan to retest under similar circumstances to see how the changes effect the actual result.  What do you think?  The model predicts that hitting the proper shift points will produce a slight improvement in acceleration.  Have you done these type of adjustments to your car before?

Go Buy a Cadillac ATS and have FUN!

The new Cadillac ATS is not winning comparison tests for acceleration.  The 3.6L V6 with 321 hp will get the ATS from 0-60 in around 5.4 seconds, which is pretty quick.  But some competitors can do better.  The 2L Turbo, 272 hp  ATS does 0-60 in under 6 seconds — Cadillac says 5.7 seconds.  Again, competitors for the 2L are quicker.

Cadillac ATS interior

Cadillac ATS interior

No one who writes for a magazine, newspaper, or website seems to like CUE (Cadillac User Experience), except perhaps me.  Cadillac designed the interface to be just like your tablet or phone, so you can squeeze this and swipe that.  CUE is not instantly responsive in all cases though, so that makes it something to criticize.  Okay.

Yet the magazine writers keep concluding that the Cadillac ATS is more fun to drive than competitors.  Let’s think about that for a minute.

The Cadillac ATS is MORE FUN than a BMW, or a Lexus, or a Mercedes, or an Audi.  You know an even more interesting thing?  I have read more than one V-Series owner suggest an ATS with a manual transmission was as MUCH fun if not more fun than their CTS-V!

Cadillac ATS roadtrip test -- ready for anything

Cadillac ATS roadtrip test — ready for anything

Isn’t MORE FUN the most important thing you want in a luxury sports sedan?

Here’s my suggestion for Cadillac’s new Ad campaign:

Cadillac ATS — It’s Fun to Drive.  It’s Fun to Own.
Go Buy a Cadillac ATS and have FUN!