Thread: AGX + Hyperco Gen II + bad roads = 40mm or 55mm bumpstops?

Hi,

I have read and searched the various suspension threads, but haven't really seen a definite answer to this.

I'm putting together an AGX + Hyperco Gen II suspension for a B13, and have some 55mm Koni bumpstops. I live in an inner-city area and drive on rough roads and get surprised by a huge pothole fairly often. Should I cut the bumpstops down to 40mm (so I'm not riding on the bumpstops all of the time) or leave them at 55mm (to better protect the AGXs from blowing out)?

On a related note, is it really noticeable when you hit the Koni bumpstops? I would think that it's reasonably smooth considering they are "soft" and progressive.

Any time you lower a car being the correct way (like the way you are doing) or in the incorrect way you need to drive a little differently. Up here is WI the roads are as bad as they come. I have to pay attention to the road and watch for bumps and try to avoid them.

As far as your question, i would try it both ways if you are concerned. Put them in without cutting them and see how it is. If you are riding on them too much you could try cutting a little off each end or if you are not hitting them much just cut off the big end. I like the Koni bump stops and its hard to tell when you hit them as they are softer and a nice taper.

I've run into this problem myself. The reason being that there are two entirely different Koni bumpstops you can buy. You may end up with one type or the other depending on where you got your advice or part #. One of them is pretty tall (55mm?) with a tapered top the other is perfect height (40mm?) with a tapered top. They are literally the same design, one is just taller that the other. The tall ones should be cut, the short ones should be left alone. For reference if you take a stock bumpstop you're looking for the Koni bumpstop to be ~10mm shorter than the stock unit. I made the mistake of cutting my short koni bumpstops because, well, everyone cuts the bumpstops right? Thankfully I didn't cut them much at all (I was really worried they were going to be too short and I ended up being right).







I've always thought the stock units should be fine after cutting off the top ring portion leaving the base and one ring. That's the advice I give now as the stock units are usually purchased anyway (come attached to the dust boots). If no dust boots will be purchased then the short Konis are my next choice.

I case it wasn't clear, I'm recommending the 40mm even though your roads are bumpy. I've got bumpy roads and less than 40mm and I'm fine. My tires rub before I hit the bump stops and that only happens with 4 people in the car and a big bump. This is with Road Magnets/AGX by the way.

What if theyer progressive's poly bumpstops?

LMK cause I am about to do hyperco and agx's on my b13 this weekend, and would like to get everything right before I go through all the hassles ya know. I can do it twice, but WHO WANTS TO LOLOLOL
the pics are here-
http://www.sr20-forum.com/showthread.php?t=8414

From the looks of them I'd leave them alone. Measure them, if they are less than 50mm I'd keep them the way they are. Might want to upgrade to a more sponge like material (OEM or Koni) if you're really looking for the perfect solution. Those should be fine though.

Thanks for your suggestions. I think I'm going to compromise and cut 10mm off to make them 45mm.

I have the koni's (not sure what mm they are, came with the set and I just put them in) on top of my AGX Hyperco GenII"s and have my AGX's set on #2 ,, only one more stiffer setting,, I did'nt cut mine at all.. and I travel 500+ miles a week for work and on every other weekend I go up to Tn to visit my parents and the road I take is 321n and it's totally screwed up from highway destruction for the last 10 yr, I show no mercy when I hit the road, I don't drive to stupid but let just say I make good time, and so far yeah I've fell of in a pothole here and there but have NEVER hit my bumpstops ,, atleast not that I know of,, whats it do? LOL my car rides pretty stilff and it took a few weeks to get used to it and now I love the fell of the road it make me more aware of what I'm driving on thats for sure, the only real thing I'm worried about hitting is ROAD KILL thats sits higher than my car that will just suk bad.

i beleive the #2 setting is supposed to be oem shock damping. Set the agx's a little higher and try it out. I am running the koni bump stops and i have never used(hit) them, and we have some ****ty roads up here. i have konis up front with agx's in the rear though.

oem huh? according to my paper work with the agx's they are saying that 1 through 4 are my choices and 4 being the softer and 1 being the hardest. mmm I'll look again but theres no way in heck my car has the oem damping feel,, this car is stiff......