racer_ace Reader
May 25, 2012 11:51 p.m.

I am installing a set of Racing Beat springs that I purchased second hand (so I do not have the installation instructions...and I could not find any on Racing Beat's website). The springs should result in a one inch reduction in ride height on my FC RX-7. I purchchased a new set of KYB bumpstops to go along with the new-to-me springs. I am not sure if I should trim them by one inch, or maybe half an inch, or just leave them as they are. Any suggestions? Thanks.

SkinnyG HalfDork
May 26, 2012 12:47 a.m.

I like drilling holes in them, softening them, to make the bottoming less abrupt.

You could "tune" this up to a point, just keeping drilling more or larger holes until you can run maximum low without losing your kidneys.

"Too much" might come quickly though, and probably not easy to get at, either....

mazdeuce Reader
May 26, 2012 6:41 a.m.

Check the ratio of free height travel to bump height and think about trying to replicate that ratio. If you cut the bump, cut from the bigger end. It will still be stiffer and by leaving the small end intact you preserve the progressive nature of the bump. That's important.

motomoron Dork
May 26, 2012 10:10 a.m.

I'd be inclined to try 'em full length and see if you end up on the stops a lot. Can you get to them to rotate them against a utility knife w/ a new blade to take off a bit? If they're down in a tube you can be resourceful and tie a string on to retrieve them...

Curmudgeon MegaDork
May 26, 2012 11:33 a.m.

I'm with motomoron, start full length and trim as/if needed. You might also pre slice them, say an inch at a time, so that you can easily reach between the coils with a utility knife and split them for removal. Don't pre split them, if you do all they will do is spread and not work.

WhiteLX New Reader
May 26, 2012 3:18 p.m.

Is there any damage that can be caused to koni struts if too much of the bump stop is removed? I am very close to the bump stops on my xr4ti and I know I am hitting them. The only saving grace is I an using 450lb coilovers.

racer_ace Reader
May 30, 2012 8:52 p.m.

Motormoron and Curmudgeon...I like your thinking! It turns out I had to cut off 3/8" from the rear bump stops to get them to fit in the OEM "cup". I can still slice and then split them if I need to take more out. The fronts are about a 1/4" shorter than stock so I left them as is. Unfortunately the fronts will be almost impossible to modify on the car due to the design of the dust boot.

Thanks for everyone's input!

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