i have no idea what the s4 or the s5 are. is the s4 the name for the tII86-88 and the s5 the tII 89-91? what are the differences?

 

yes you have that correct. except thats for all the models just not TII's

 

As found in the FAQs

Series 1 / S1 = 1979-1980 RX-7 models
Series 2 / S2 = 1981-1983 RX-7 models
Series 3 / S3 = 1984-1985 RX-7 models
Series 4 / S4 = 1986-1988 RX-7 models
Series 5 / S5 = 1989-1992 RX-7 models
Series 6 / S6 = 1992-1995 RX-7 models

 

there are some pretty significant changes in the 1999 and up FDs, are they series 7, or does anybody know?

 

what are the differences? are they different computers? different management systems?

 

They stopped bringing the RX-7 to the US in '96, so the '95 is usually the newest you will be able to find.

 

I will have to add this to my info page for mazda transmissions. There is a mod guide page for mazda 5 speeds on my site, probably won't help the 7 community much but if you want lower 1st-4th gears to wine it out more you can modify your tranny with a miata. Here is the page:

http://www.angelfire.com/darkside/de...nsmission.html

I still have a tranny or two to take appart and I'm putting a S5 Conv tranny in my pickup truck so the pages will be under construction for some time, but most of the vital information is there.

 

damn man you are hardcore about some farkin transmissions....tear it up dogg!