Hey guys,

On a B13 with AGXs, lowering the car 1.5 to 2.0", should I get 7" or 8" GC springs? What would be the difference between the two? When do you use a 7" and when do you use an 8" spring?

Thanks,

I wouldn't go as low as 2" with the AGX's. You'll be crashing on the bump stops. How do I know this? I ran the GC/AGX setup for about a year (on 7" 300f/200r springs) and recently just upgraded to custom made shortened struts with Koni race inserts and the difference is almost like night and day. Plus, when we took off my old AGXs, we saw that my bumpstops had been compacted to 1/2 of the size they once were. And those Truechoice polycell bumpstops were like $15/each!!

But, to answer your question, 7" should be fine. Go 8" if you plan to upgrade to shortened struts in the future, but 7" springs still work - I'm running those now with my cool new struts. :)

Got it. 7" with non-shortened struts, 8" with shortened struts.

I forgot to mention that I will be installing Ground Control camber plates in the front and I will be modifying the rear upper mounts, thus giving me about an inch worth of additional travel. So, a 2" body drop would really be only a 1" drop relative to the struts, right?

What do you think about this? A 1" drop should be okay I would think.

Either springs will work fine with non-shortened struts. But, if you're using GCs camber plates w/ shortened struts, you will NEED 8" springs.

I say whatever you do, just make sure you have at least 2-3 inches of free travel (ie not including space the bumpstop takes up). That should be ok and keep you off the bumpstops in most road conditions.

Alright, let me get it straight. I am using non-shortened AGXs, GC springs, GC camber plates, and I am modifying the rear upper strut mount (making it shorter for more travel). So, will a 7" spring be okay here?

I don't want the car to be too low and not be able to raise it up to the right height because I have run out of threads on the collar.

Yes, you will be good.