Popping noise at high lateral G-Loads (front of car)
 

So I think I have an issue developing on my car and I thought I'd get some opinions. Basically I messed up on my pad bed in on my Essex kit and developed some nasty judder towards the end of two weekends (I thought I had fixed it after the first by running track pads on the street for a while, I can give more details if anyone is interested :( ). Anyway, I am starting to get popping noise from the front right suspension as I go through high G-force corners. Looking at the suspension I'm thinking that the bushing on the anti-roll bar is looking funny (a little squished). Also, the noise only happens at very high G-load. I am going to take it to a mechanic tomorrow and see what they say. I don't have a photo of the bushing now, but I will get one and post it tonight in case anyone is curious.

Anyway, to the meat of my question, assuming I messed up a bushing and everything else is fine, is it better to just get a OEM bushing to replace it or should I order a set of more firm ones? If I were to upgrade just the anti-roll bar bushings, what would the effect of that be?

Thank you

Any videos of the noise?

Stock suspension? Stock sways? Tires? Rims?

Suspension is completely stock (including alignment). Rims are Enkei PF01 18x8.5 +48mm with 225/45/R18 Yokohama Advan AD08R. I might have video of it but I filled up the memory card on my in car camera in the last or second to last session so I don't know if I actually got any of it (I haven't looked at the data from the camera yet). I would generally describe the sound as similar to clogs of rubber being picked up and chucked by the tires except that it happened as I enter and exit high G corners. Also it happened too much to be just track crap being picked up and tossed; not to mention I was on the normal line so there shouldn't have been much there.
This was the ninth track day I've done in this car and was doing about 2:21-2:22 at Thunderhill (which I think is low to middle intermediate level).

The brake judder was pretty rough which is why I gravitate towards it being the source of the issue. It is embarrassing, but I think I did a really, really, really small amount of bend on the disk by trying to lever it (just by hand) against the pads to push the pistons back into the calipers when swapping pads (as in, super small amount). I think this time was the first time I REALLY got the pads hot enough to get substantial bedding-in done but then not enough to overcome the reduced heat on the other half of the rotor. From a quick inspection it looked like the rotor has one half of the outer face nice and greyish while the other half is silvery. I will know more when I pull the rotor off later this week though.

Keep me posted.

A poping sound is unusual.

Yeah, it has me a little worried. The car was still handling normally as far as I could tell and I didn't notice any destabilization as the popping was happening so I don't think it is preventing the car from transferring weight / I don't think anything is binding/slipping to strongly. I am going to dig into it tonight and see if I can figure anything more out; I am signed up for the Porsche club at Buttonwillow this weekend and I really want to go (not just because it was a more expensive event, but also because I want to get some solid instructions on the specifics of that course to get me as comfortable as possible for the Lemons there in June).

Good news! I took it to the mechanic and it looks like one of the bolts on the lower control arm was a little loose. They re-torqued all the suspension bolts so I should be good to go! I guess in the end I will only REALLY know for sure come this weekend of course, but still, I am hopeful!

Also, the funny look on the bushing was probably because I had the car jacked up using the side point instead of the center point (so the anti-sway bar bushing was being compressed).

A lot of the track guys(especially with older cars) mark a lot of the suspension bolts with a paint pen after torquing them. They draw a line from the center of the bolt onto the surrounding metal. This way you can do a quick visual for any that are coming loose.

That is a good idea, I will have to do that. Do you know what kind of paint they use?

Generally you can just use a thick-tipped sharpie paint pen for that. I don't know how it would last long term, but it should be a long long while.


Sent from my iPhone using Tapatalk

The common word used for this paint-pen marking is "indexing". Now that you know, you'll see it a lot more. I index things that rotate or vibrate a great deal. Axle nuts, crankshaft pulley bolt just to name a couple. Indexing can also be done with a chisel and a hammer to make a small indent but for most things a silver sharpie works fine.

Indexing allows a pre-track nut an bolt check to be done with a flashlight and your eyeballs without having to put a wrench on every nut.

Anything... I can pick one up from Daiso and mail you one for like 4 bucks.

Daiso... Is that the same Daiso as the Daiso in Japan? Totally off topic, but good memories.


Sent from my iPhone using Tapatalk

Yes!

They're popping up everywhere in Cali.

I lived in Japan for a few years while taking a break from college -- while I was still poor. Those things were a godsend at the time. Crazy that they're showing up in CA. Must mostly be down south, haven't seen any during my frequent trips to the Bay Area.

Anyway, y'all can get back on topic now... Haha.


Sent from my iPhone using Tapatalk