Need help diagnosing front suspension noise under load
 

Turning left or braking car developed an unusual suspension knock. You can hear it here:
Finally just called it quits. Does not appear that swaybar is hitting swing arms. Just had camber done (-2.75 front and -2-25 rear) and because concern with bolts coming loose, installed new 2005 bolts. Also have racing beat sway bar blocks that I thought may have come loose, but they were tight (gave the nuts an extra 360 turn just in case. One of the camber plates moved just one notch on the adjustment, but I don't think that'd do it. Damn mystery. Struts are Feal 441 with 9k, 6k springs set 2 and 4 clicks off full hard.

Any thoughts?

Top mount bolts tight?

get a nice long prybar and check all the control arm bushings, and anything else suspension/bushing/mount related. Prybars are your friend. I think i made more money with a 25 dollar Sears special than any other tool.

use it to put pressure on joints. Dont push too hard, and make sure you keep the edge flat/straight so you dont mar any surfaces.

I just tracked down a "clunk" that was similar that took us a year to track down - it was the rear upper inner control arms. I had used a little bit of teflon lube on the metal inner part of the bushing to help seating them after we did replacement rubber bushings. The bushing would twist and then "snap" once there was enough force - and similarly, it would sometimes creak and sound like it was a loose tophat bolt rubbing up and down the threads. Took forever to find because prybars and hoist jacks wouldn't recreate it - finally putting it on the lift and going up and down made it pop.

DP

Subframe mounting bolts had me chasing around for a while, only happened when cornering, only in one direction and only when heavily loaded over a rough surface. Those bolts need a big rattlegun, or a long extension handle.

Do you recommend that the suspension be weighted while testing for slop with the prybar? car is on jackstands but I can load the tires with floor jacks. I also wondered about the subframe. Those are some big ass nuts and bolts. Also going to check the steering rack bolts. Basically go over everything I can think of with a torque wrench. Good suggestions. Thanks.

Were you able to get it to stop by greasing the bearings? I've got the same tophat bolt sound and I've recently swapped out bushings as well. I've installed zerk fittings so I may just grease the crap out of em. Just curious as to how you fixed your problem.

What did you torque the control arm bolts to?
In order to keep them from slipping with sticky tires you need to torque high enough that they are yielding.
I had a similar noise early this season, so I replaced all the front lower control arm bolts and also installed the Flyin Miata eccentric locks. It was a clunk/pop coming from the front under braking and or cornering. With the locks installed, I torqued them to 85 ft-lbs (per the FSM) and had zero noise or slipping at NCM.

The opposite - I degreased the bushing and control arm faces. Again, these are rubber replacements, not polyurethane.

Fixed
 

Problem fixed (went back to the same track – no clunk.) I torqued the subframe (very slight movement) the steering rack (no movement) and the top mount bolts (slight movement.) I also added a full rotation on the nuts that pre-load the Racing Beat sway bar mount blocks and torqued the bushing bolts. I think most significantly, the newly added 2005 front passenger side camber bolt was not all the way tight as the front cam had moved about an 1/8th of an inch from the alignment shops scribe and the nut was not all the way tight. Had a bit of a time trying to match the scribe on the cam on the bolt side with the scribe on the cam on the nut side but was able to basically line them up and torque to 100 ft pounds. And I re-adjusted the Good-Win adjustable endlinks to their shortest length. (when I put on the new coilovers I’d matched the endlinks to the prior endlink but instead of being at 12.5 front 12.75 rear I’m now at 12 front 12.25 rear.)

So, who knows exactly what it was but I’m glad it’s gone. Thanks for the suggestions.

I am definitely thinking of getting the Flyin Miata eccentric locks though. Took it back to the shop to re-check the alignment after tightening the bolt and they said I was still at -3 front and -2 rear. Car pulls slightly to the left though so going to take it to a different shop next year, one with the computerized printouts.