You may already know this but OEM MSP springs are a bit shorter than many aftermarket springs due to the OEM MSP struts having a higher spring purch on the rear strut. If OEM MSP springs are installed on a standard protege/5 without the proper MSP strut it will cause the rear of the vehicle to be lower than the front of the vehicle.
So due to that you may want to stick with Non OEM (Racing Beat etc) springs due to the slightly longer spring and ability to use many aftermarket struts.
Keep in mind if you are planning on upgrading your sway bar it is recommended that the sway bar link mount on the strut be reinforced due to the addition stress put on the mount by the sway bar. It is recommended to purchase struts with a reinforced mount (tokico hp). OEM MSP Struts have this reinforced mount also.
If you want that pure MSP suspension then OEM MSP Springs and OEM MSP Struts are what you want but it will cost ya a bit.
MS Retuned Strut Kit - Mazda Part #0000-8M-C14
I believe the kit comes with bump stops so that will save you a few dollars. I am sure you could find these cheaper but here you go:
Struts
Picture
OnlineMazdaParts.com Part #0000-8M-C14 $531.77
Springs
OnlineMazdaParts.com Part #0000-8M-C13 $280.29
If you are looking for True Racing Beat springs you could check out Racing Beats Site:
Racing Beat Part #74080
Price $210 + shipping.
The best price I found on the springs is $195 at ProtegeGarage.com due to them having free shipping.. they are drop shipped directly from Racing Beat.
ProtegeGarage.com RB Springs
It is recommeded that you use shorter bump stops when using lowering springs:
Racing Beat Part #74012 $11.01ea
OnlineMazdaParts.com Part #BN7H-34-111 $8.59ea
Another thing is the RB and OEM MSP springs will only lower the car about 3/4 of an inch. That may not be low enough for the look your going for. You may want to look into other brands of springs (Tien, Espilers, etc) for something that will lower the car even more
These are not Racing Beat springs but I do have a set of OEM MSP Springs new in the box. $75.00 shipped to SC. You will want to match them up with OEM MSP Struts.
Part Numbers:
Mazdaspeed Spring kit #0000-8M-C13
Rear Springs #BP7H-28-011
Front Springs #BP7H-34-011
OnlineMazdaParts.com Part #0000-8M-C13 $280.29
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