I don't believe they're the same. Both my old shop from when I lived back east, and my shop out here have told me the same thing: the e30 blipper has one less tooth. It needs to send less blips to the counting circuit in the speedo, since the tire/wheel size on the e30 is smaller and covers less ground per wheel rotation. I've also read that in more than one place, but I can't remember exactly where (old man disease... ;-) Assuming this is true, you'll be covering more ground per wheel rotation in your e23 than the speedo is accounting for. If my logic is correct, you'll be going somewhat faster in real life than your speedo says you are.

I'll be looking forward to your results. If it turns out that all my information has been wrong all this time, that means one less step in my own conversion.

You might want to just go find a local speedometer shop in your town and have them just run the car up on their dyno - that will tell you in just a few minutes. That's what I do out here - costs me $20 and I know exactly where my speedo stands relative to actual road speed.

• My Differential Project with instructions and photos (pic) - ejonesie22 2008-04-11 15:19:04 (658 views)
  • Question... - mofinco 2008-04-14 00:22:32 (135 views)
    • Re: Question... - ejonesie22 2008-04-14 16:32:14 (113 views)
      • Re: Question... - mofinco 2008-04-14 20:05:04 (130 views)
        • Ok, here is what I found... - ejonesie22 2008-04-21 09:47:49 (108 views)
          • That's GREAT! - mofinco 2008-04-22 14:43:57 (102 views)
            • Re: That's GREAT! - ejonesie22 2008-04-25 16:33:29 (87 views)
              • No doubt... - mofinco 2008-04-28 00:42:59 (91 views)
    • What are you doing with the 3.46? (nt) - demet 2008-04-14 08:59:38 (112 views)
      • Re: What are you doing with the 3.46? - mofinco 2008-04-14 20:06:39 (120 views)
  • Nice write-up, Evan, Here are a couple more points - kff 2008-04-12 18:29:40 (123 views)
    • Yes. I should have pointed out it was my North American 733i I did this on... - ejonesie22 2008-04-12 20:16:49 (127 views)
  • Good info. - demet 2008-04-11 18:09:55 (94 views)
    • Its a permetex gasket dressing that comes in twist stick tube. - ejonesie22 2008-04-11 18:16:28 (114 views)
      • Is a sealer necessary? - stevebu 2008-04-27 07:49:37 (86 views)