Good question that would be a good addition to the FAQ...

Does anyone know the spring rates of the Protege's stock springs and the various brands of aftermarket springs?

Here's what I've found on the Web:
Tein S.Tech springs: 179 lb/in front, 145 lb/in rear
Tein Super Street coilovers: 336 lb/in front, 280 lb/in rear
Mazdaspeed Motorsports Development SSC trunk kit: 325 lb/in front, 600 lb/in rear (crazy stiff!)
AWR Racing street coilover kit: 275 lb/in front, 325 lb/in rear

Anyone have any other info?

 

Does anyone know what the stock spring rates are for the MP3??? I have been searching everywhere for an answer and have not been able to find an answer...

 

I would like to know this as well!

- Brian

 

Yeah and what about H&R's and Eibachs. I have emailed Advanced Imports and a few other places trying to compare S-Techs to the european springs with no avail...