6-Speed Transmission Differences by VIN
 

I'm considering putting a 6-speed into my Miata. I understand that the Mazdaspeed Miata Transmissions were shot-peened and so probably are a little stronger. They're a little harder to come by, so I'm looking at non-MSM as well.

For the non-MSM transmissions, are there any strength/longevity differences between these transmissions? I read about different shifter turrets and fulcrums, but wasn't sure if this had any impact on strength.

Thanks in advance!

I didn't know of any differences.

Thanks, Six, appreciate it!

They all break in fourth gear at around 300-350WHP.