Compiling 915 transmission gear ratio documentation
 

Greetings. I have combed the bboard a bit and was not able to find complete documentation on 911 SC / Carrera gear ratios for the various years. Perhaps we can compile a complete chart here so that all the info is in one place.

Specifically, I'm looking for 1980 US (911/63) vs. 1984 US (911/68).

My starting point expanded by recent posts, still need more detail:
(damn newlines make life easier but add whitespace here!!)
<table border=1><tr><td><b>Year</b></td><td><b>Model</b></td> <td><b>Loc</b></td> <td><b>Part #</b></td> <td><b>Ratio</b></td> <td><b>1st</b></td> <td><b>2nd</b></td> <td><b>3rd</b></td> <td><b>4th</b></td> <td><b>5th</b></td> <td><b>Notes</b></td> </tr>
<tr> <td>1972-3</td> <td>911 T/E/S</td> <td>US</td> <td>915/02</td> <td>7:31</td> <td>11/35</td> <td>18/33</td> <td>23/29</td> <td>26/25</td> <td>29/22</td> <td>Magnesium</td> </tr>
<tr> <td>1972-3</td> <td>911 Carrera</td> <td>US</td> <td>??</td> <td>7:31</td> <td>11/35</td> <td>18/33</td> <td>23/29</td> <td>27/25</td> <td>29/21</td> <td>Magnesium</td> </tr>
<tr> <td>1974-77</td> <td>911</td> <td>US</td> <td>915/43</td> <td>7:31</td> <td>11/35</td> <td>18/33</td> <td>23/29</td> <td>26/25</td> <td>29/21</td> <td>Magnesium</td> </tr>
<tr> <td>1977</td> <td>911S</td> <td>RoW</td> <td>915/60</td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> </tr>
<tr> <td>1977</td> <td>911 Carrera</td> <td>US?</td> <td>915/60</td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> </tr>
<tr> <td>1977</td> <td>911</td> <td>US</td> <td>915/61</td> <td>7:31</td> <td>11/35</td> <td>18/33</td> <td>23/29</td> <td>26/26</td> <td>28/23</td> <td>asymmetrical dog/slider teeth, more robust silder hubs, first omega clutch assist spring, magnesium or selenium</td> <td> </td> </tr>
<tr> <td>1978-83</td> <td>911SC</td> <td>RoW</td> <td>915/62</td> <td>8:31</td> <td>11/35</td> <td>18/33</td> <td>23/29</td> <td>26/26</td> <td>28/22</td> <td> </td> <td> </td> </tr>
<tr> <td>1978-??</td> <td>911SC</td> <td>US/Jpn</td> <td>915/63</td> <td>8:31</td> <td>11/35</td> <td>18/33</td> <td>23/29</td> <td>26/26</td> <td>28/23</td> <td>Omega springs needle bearings, casting Silumin</td> </tr>
<tr> <td>1978-79</td> <td>911 SC</td> <td>US/RoW</td> <td>915/61</td> <td>8:31</td> <td>11/35</td> <td>18/33</td> <td>23/29</td> <td>26/26</td> <td>28/23</td> <td>Aluminum (stronger, heavier)</td> </tr>
<tr> <td>1982-83</td> <td>911 SC</td> <td>US/Row</td> <td>915/62</td> <td>8:31</td> <td>11/35</td> <td>18/33</td> <td>23/29</td> <td>26/26</td> <td>28/22</td> <td> </td> </tr>
<tr> <td>1980-83</td> <td>911 SC</td> <td>US/Jpn</td> <td>915/63</td> <td>8:31</td> <td>11/35</td> <td>18/32</td> <td>23/29</td> <td>26/26</td> <td>28/23</td> <td> </td> </tr>
<tr> <td>1980-83</td> <td>911 SC</td> <td>US/Jpn</td> <td>915/63</td> <td>8:31</td> <td>11/35</td> <td>18/32</td> <td>23/29</td> <td>26/26</td> <td>28/23</td> <td> </td> </tr>
<tr> <td>1978-83</td> <td>911 SC</td> <td>US</td> <td>915/40-44-60-61</td> <td>8:31</td> <td>11/35</td> <td>18/33</td> <td>23/29</td> <td>26/26</td> <td>28/23</td> <td> </td> </tr>
<tr> <td>1980</td> <td>911 SC</td> <td>US</td> <td>915/63</td> <td>8:31</td> <td>11/35</td> <td>18/32</td> <td>23/29</td> <td>26/26</td> <td>28/23</td> <td> </td> </tr>
<tr> <td>1984</td> <td>911 SC</td> <td>US</td> <td>915/68</td> <td>8:31</td> <td>11/35</td> <td>18/33</td> <td>23/29</td> <td>29/28</td> <td>38/30</td> <td> </td> </tr>
<tr> <td>1984</td> <td>911 SC</td> <td>RoW</td> <td>915/67</td> <td>8:31</td> <td>11/35</td> <td>18/33</td> <td>23/29</td> <td>29/28</td> <td>38/30</td> <td> </td> </tr>
<tr> <td>1984</td> <td>911 SC</td> <td>RoW</td> <td>915/67</td> <td>8:31</td> <td>11/35</td> <td>18/33</td> <td>23/29</td> <td>29/28</td> <td>39/29</td> <td> </td> </tr>
<tr> <td>1984-86</td> <td>911 Carrera</td> <td>US</td> <td>915/68-70-73</td> <td>8:31</td> <td>11/35</td> <td>18/32</td> <td>23/29</td> <td>26/26</td> <td>38/30</td> <td> </td> </tr>
<tr> <td>1984-86</td> <td>911 Carrera</td> <td>RoW</td> <td>915/67-69-72</td> <td>8:31</td> <td>11/35</td> <td>18/33</td> <td>23/29</td> <td>29/28</td> <td>38/29</td> <td> </td> </tr>
</table>

Also helpful to add brief comments like 'aluminum box starts this year, increased strength & weight'

I will compile all of it into a nice concise HTML table and repost when reasonably complete.

Thanks muchly!

If you don't have access to the shop manuals or spec books maybe start here at "Instant G" look towards the bottom of the page. Steve uses a non standard way to represent the ratios but it's preety good otherwise

also lots of info avaialble from 'search'

magnesium trans cases were used from '72 to '79 on E thru K series n/a cars
915/02 was the first version in '72 and 915/73 was the last version in '86, there were also several 4 speed versions