are koni bump stops still the best ones out there?

Any other better options for progressive, quality, tunable (knife) bump stops?

Where do you guys like to buy yours?

I'm still freaked out by the notion that bumpstops are a suspension tuning item on any vehicle not sporting a lot of downforce...

I thought it was pretty weird too, but Carroll Smith seems to like them.

I'm considering these as starting points

http://www.summitracing.com/parts/ENS-16-9102G/?rtype=10

Anything will run out of travel at some point. There's always a bump big enough

In reply to Keith:

Oh, I'm not doubting the importance of bumpstops by any means. I just mean that no matter what they're shaped like or made of, the rate is going to go near-asymptotic Right The Heck Now, relative to a spring, and I figured that bumpstops are for making the travel-remaining/no-travel-remaining transition nicer, not tuning handling (again, on non-aero cars).

But I didn't mean to threadjack. Taiden's question was about the best bump stops, not whether or not they're of an effectively tuneable nature.

I should go re-read Smith on bumpstops. ISTR that a lot of what he said was biased towards pure race cars, frequently with wings, and production based cars got a separate addendum in Tune to Win, but I don't recall whether bumpstops were addressed separately there.

Okay, really stopping the threadjacking, and returning you to your regularly scheduled useful responses.

I know a lot of folks who say these are awesome...

http://www.fatcatmotorsports.com/FCMstops_comp.htm

I used ZQ8 bumpstops from the s10 extreme on my Impala SS and loved them. I had around 1/8th of an inch or so of free travel before the bumpstops contacted the lower control arms. I will say that these "newer style" bumpstops are a world apart from the old rubber ones. I certainly was able to use them as a tuning aid.

When I commenced learning Miata suspension bump stops are all everyone was talking about. As in "the rear suspension spends much of it's life on the bump stops, so you must buy XYZ..."

So I called Flyin' Miata and said "Here's my credit card number; I want to do the following things - please tell me everything I need to do all of it, and anything any right thinking individual would do while the bastard is apart. Do no tell me what the total is..."

And I got whatever bump stops come w/ the FM stage 2.5 suspension package. They're white urethane foam and look like Konis, but I've no idea.

On my D sports racer they're whatever comes w/ Penske shocks - they're not very big, and from pictures of the car at speed - and the aero is as much as I can get still - the ride height doesn't seem anywhere near bump stop contact levels of compression. I may be going too slow.

Motomoron, you have 54mm multicellular urethane bump stops. They're longer than some other people recommend for our springs, but that's because they give a much nicer transition on to the stops so you don't get as strong a spike in spring rate. Makes for a better ride and (in my opinion) more consistent handling than the shorter ones. See, they are a tuning tool!

Thanks, Keith. This I know about the car: It works great, all the time. FM stg. 2.5, chassis rail and butterfly braces, urethane bushings everywhere, Star Specs on 7x15s.

It's my "car I don't mess with".

ransom wrote: I'm still freaked out by the notion that bumpstops are a suspension tuning item on any vehicle not sporting a lot of downforce...

Pretty handy in the stock-class world where bumpstops and shocks are open but springs are not. Especially on a DWB suspension where you can use a ton of rebound to jack the car down onto the bumpstops after a couple turns. Now your "stock" car has gobs of camber and a very high spring rate. :)

motomoron wrote: Thanks, Keith. This I know about the car: It works great, all the time. FM stg. 2.5, chassis rail and butterfly braces, urethane bushings everywhere, Star Specs on 7x15s. It's my "car I don't mess with".

That's what I like to hear! Glad you're enjoying it. It's not far off the spec of the Miata I drive every day, just add the word "prototype" in front of every part

And I have been informed in no uncertain terms by Janel that I am not allowed to change the suspension on that car any further.

What is the spring rate on those bumpstops, Keith? (If they are linear-ish)

Approximately 100 lb/in, but they go non-linear after about an inch.