Control arm bottoming out on body
 

xidas+spherical tophats
700/400
Xida bump stops
Delrin bushings

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Anybody seen this before?

Current plan is to trim the body and see if that helps.

Why not try some bump stop packers in the short term before cutting metal out near the shock tower?

Because i'm lazy and would rather cut than pull a shork. Also i dont want to lose travel. I think I should be able to trim it out a little bit and be fine. I believe the lower is also contacting the subframe somewhere.

Packers are slitted so you can pop them on the shaft without pulling the shock.

Maybe not the ultimate solution, but it gives you time to investigate without cutting up your car.

Ahh, i'll look into those. I really don't mind cutting the car. And it looks like as long as I bend that lip back up it shouldn't matter a whole lot.

:fael:

But yeah, the packers are just cut plastic ring things that you pop over the shock shaft. You could probably make some with whatever you have laying around.

That, or stiffer springs to keep from bottoming out.

I doubt stiffer springs will help. Unless they are like 2000# springs. These are from hard slams, not turning or anything.

Stop offroading your Miata? :)

--Ian

im not surprised with this at all. more spring will help for sure. i ran around 3 degrees camber once out back and hit a curbing just right that the bolts holding the shock mounting area to the frame cut into the backside of my rim.

also gen2 ftl

You really think an extra 100# of spring will help this.....thats not how this works.

Why gen2 ftl.

I'll take a photo of my LR corner with the exact same parts at full bump w/o spring for comparison tomorrow.

Do it with and without a bumpstop too if possible so I know how much the bumpstop has to compress to get to this point.

You're killing me.

But seriously, I think there's no way I can photograph that perspective showing the bumpstops with the billet mounts.

Don't need pics. Just measure from the top of the billet mount to the top of the shock when control arm touches body.

iv handled both gens and gen 2 have a cheaper build quality.


what ride height are you out back. and did you go from nb top hats to billets and the contact is a side effect?

Always been on billet.

Gen 2s have bigger pistons and are doubly digressive. No idea what world that's "FTL" in.

Ride height also doesn't matter here.

excuse me i get caught up in perceived quality and value too easily.

back to the topic

what are our options here.

bent arm thats bowed. shock body is too short. bump stop is too short. upper shock mount is too high.

the idea of more spring is to keep the suspension off the bump stop as much as we can.

can you pull the spring out and check for contact when the shock is just touching the bumpstop?

Arm could be bent. I could put a straight edge on it tonight.

I'm far too lazy to pull the spring out. If I go that far I'm just going to cut where it is hitting.

AFAIK i am the only person with this issue, which theoretically rules out shock, bump stop, and upper shock mount issues.

I wonder if there are just differences in each chassis.

either stop doing sweet jumps or dont be so stanced bro.

JJFU. I have never seen that kind of contact before and i have had some dumb low miatas in the past.. Do you know when it did it? i imagine you would have felt it bottom out.

Ughhh. Come on guys.

Ride height does not affect this at all. I could be stance bro low and never have this issue, because I drove like a sissy.

No idea exactly when this happened. Hitting a big ledge at 60 feels like shit even hitting bumpstops.

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https://cimg4.ibsrv.net/gimg/www.mia...fb5cb94589.gif

BTW

Comp weight?
Pinch weld heights?
Tire size and compound/model?

Weight: your guess is as good as mine. Probably ~2300 depending on when I shit last. Not a competition car.

4.25"f 4.5"r

225 rs3v2s
i know if at least 4-5 "oh shit that curb hurt" moments in the past season. Could have come from any of those. I hate ORP in that regard. Dropoffs are steep.

All that looks good. Stop crashing into the things.

I hear that a lot actually.

We're gonna start calling you Danica.

OK, that's just mean. I was going to say Maldonado. :)

--Ian

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I have 5mm room between the RUCA and rear shock tower at the beginning of bumpstop engagement.

To get contact, the bumpstop has to compress to 19 from a starting length of 23mm.

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I get RUCA contact before tire contact at the fender top.

Just don't spin over any orange curbs at Laguna :)

5mm sounds like not very much to compress a bumpstop. Anybody know what the "block" height is for those bumpstops?

As mentioned earlier, make sure your NB mount rear Xidas have two bushing beneath the shock mount.

I am on BCM. Not sure about afm.

Caught that. I live in a world of search engines and forum threads. I mentioned that for the guy that does a google search, finds your thread (having NB mounts incorrectly installed) and needs an answer.

As you were..

Mine does that. or I should say did. Now the chassis side is bent out of the way enough it doesn't. Also have the nice rub marks on the inner fender directly above the center of the tire indicating 100% use of bump travel.

Interesting.

What would be a better option. Trim chassis? Or lower the shock mount.

Trimming the chassis would give me more travel, which according to the top of my fender well I really don't need. But lowering the shock mount without changing ride height would give me a net loss of travel.

looks to me you have just enough rubbing to say you have maximum usable bump travel. The A-arms are just kissing the frame. Its actually mostly just the lip on the sub frame. A hammer will clearance things right up.

Now that is a tool I'm good with!

Its also interesting to note the angle of the upper A-arm when that occurs. extreme levels of camber gain at full rear compression on these cars.

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--Ian

Me too

I notched the UCA on my car:
https://goo.gl/photos/UMyp8US6zp49M6726

What in the flying fuck is that? Why would you do this?

I really hope that's a joke of what you did to an already bent UCA...

Some people will plunge a 4.5" angle grinder into anything these days...

I plunged something 4.5 inches long into your mom last night.

Faeflora style ftw

I think he did that because of SCCA Solo rules which prohibit you from touching the body of the car for clearance yet allow mod/replacement of a (upper or lower) control arm. Not defending the action, just providing a possible answer.

Is a control arm allowed to clearance the body? Solution: Embiggen the contact area of a spare control arm with a steel plate and jump some train tracks.

Well yes, rubbing and self clearancing? is allowed. Also, you are allowed to clearance towards the outside of the track (rotor to wheel mounting surface) but this is inside of that. Solo rules are "WTF?" sometimes.

In any case, OP has an easy solution for his racing habits: BFH.

Can you make a control arm with a die grinder attached to the top of it? :)

--Ian