Kevin K2

Used excel to plot out axle torque vs mph in ea gear, to find optimum shift points, assuming good traction. For an A4 with PES T-28 torque curve per link, worked out that going to redline was best for ea shift. For a chipped K03 with peaky torque curve, would likely be less than redline (no torque curve found). Sound right?<ul><li><a href="http://www.volksdraggin.com/t28dyno.htm">fwd 1.8T PES T-28 dyno sheet</a></li></ul>

Audi2ptzero

and under 7000 going into 4th.

Kevin K2

if you have excel (or ms word for dead copy), i can e-mail you the program. shows for that linked torque curve, should also redline 3rd. can plug in your own torque curve.

Audi2ptzero

You also have to take into account that each gear takes longer to reach redline. This means in 3rd gear you spend more time well past the hp peak then you do in 1st and 2nd. It also means your stalling your mph during that time.

Kevin K2

always good to compare theory vs experience. bottom line is to keep torque at axles as high as possible ... the shift point is apparent looking at the cascading 'torque in gear' curves. Need to have torque curve from mfg or dyno (program uses 12 torque/rpm data pairs from a curve), gear and final drive ratios, and tire size. program does rest.

Audi2ptzero

you will find that the tq falls off before 5K rpms and the hp peaks at 6k rpms. For you to stay any where near the tq peak you would have to shift so you fall down below 5k rpms in the next gear.

Here is my 100 octane pull with a PES T28. As you can see the tq level at even and early 6400 rpms is equal and falling to the tq level at 4k rpms.

<img src="http://pictureposter.audiworld.com/1346/m09-run3.jpg">

Kevin K2

7k into 2nd and 3rd. Into 4th would be 6500, and into 5th at 6400.


mph3 T3 mph4 T4
58.0 1226.7 76.0 936.5
60.8 1279.5 79.6 976.9
63.5 1306.0 83.2 997.1
66.3 1327.1 86.9 1013.2 &lt;- 4800
69.1 1311.3 90.5 1001.1 &lt;- 5000
71.8 1279.5 94.1 976.9
74.6 1269.0 97.7 968.8
77.4 1237.2 101.3 944.6
80.1 1194.9 104.9 912.3
82.9 1120.9 108.6 855.8
85.6 1094.5 112.2 835.6
88.0 1036.3 115.3 791.2

(see rpm list below)

col 1 = engine rpm/1000
col 2 = eng or dy torque
col 3 = calc'd hp from tq


4.2 232 186
4.4 242 203
4.6 247 216
4.8 251 229
5 248 236
5.2 242 240
5.4 240 247
5.6 234 250
5.8 226 250
6 212 242
6.2 207 244
6.37 196 238

1st 3.778
2nd 2.176
3rd 1.429
4th 1.091
5th 0.865
final 3.7

tire w, mm 215
asp ratio,% 55
rim, inch 16

Audi2ptzero

=)

Kevin K2

I didn't click on the 7k redline .... had 6.5K redline in head when I said to redline 3rd.

good to know my program matches your findings

AXE

Mail me the spreadsheet and i'll host it online for everyone