We know MAZDA designates a series of rotrs by Alpha designations, but what EXACTLY does it mean? When you order a new rotor from MAZDA you are not asked for a Alpha designator within that series (TII,NA and year model).



So what differentiates the various rotors?

I thought it was the slight weight difference in them due to casting inperfections... Go and ask the dealership they should know. https://www.nopistons.com/forums/pub...DIR#>/wink.png

If it WAS a weight difference, then you would be able to order the rotor designation from the factory. Time for a call to SCOTT

could it be different manufacturing sites/machines?

[quote name='Cheers!' date='May 13 2005, 03:46 AM']I thought it was the slight weight difference in them due to casting inperfections... Go and ask the dealership they should know. https://www.nopistons.com/forums/pub...DIR#>/wink.png


[/quote]



the mazda parts system says, any new rotor for a given application will work in that application. for the 79+ cars there is only 1 part number for a rotor for a given engine "series", except the 12a and renisis which have front and rear rotors that are different. so for example for a non turbo 89-91 rx7 there is one part number for the engine rotors, and it will work in any 89-91 non turbo engine.



to find a factory reference to the letter designations you have to go back to the pre rx7 stuff.

I think it was 2 gram deviations between the letter codes.

"A" being the heaviest, and "E" being the lightest.

So, on average, "A" versus "E" would be 8 grams.





-Ted

[quote name='RETed' date='May 16 2005, 09:38 AM']I think it was 2 gram deviations between the letter codes.

"A" being the heaviest, and "E" being the lightest.

So, on average, "A" versus "E" would be 8 grams.

-Ted


[/quote]



Difference between the S5 NA B and D rotors I had was 46 grams

isnt the turbo rotor lower cmprosison compared to the n/a

[quote name='slimeball' date='May 25 2005, 04:46 PM']isnt the turbo rotor lower cmprosison compared to the n/a


[/quote]



Correct.