When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Just got back from a weekend at Summit. The car did well, no major issues to report. The 1.5 way LSD makes a hell of a racket in the paddock as the wheels skip and chirp in turns, but works very well on the track putting the power down in the corners. The suspension height is good, there was no fender rubbing whatsoever. I started with both front and rear coil-overs set to 18 out of 24. That was too stiff for the light rear of the car making it jump and lose traction on every little bump. Went down 6 clicks in the back to level 12, that made a huge different in traction and my comfort levels. Later I tried going even softer to 14 front and 10 back, which might be good for bumpy tracks like summit but probably too soft for smoother tracks like VIR.
Still fighting a bit of an over-steer, the rear wanted to step out if I got on the throttle too hard in the corners. Next step will be to try removing the rear sway bar, which should provide more bite and with 10K spring rates is likely not required. Also there was some under-steer still present with car washing out in high speed sweepers, I'm attributing that to not enough front camber, so adjustable front controls arms are next on order.
Overall a successful test and tune and I'm now considering going back to VIR in April for some open track time.
A few laps from last weekend. The car tended to wash out in turn 10, 1:29 was the best I managed. I think with proper front camber and a bit more rear grip I can knock that down a few more seconds.
Also, I just received word that VIR has shut down for at least next two weeks, and likewise Summit Point events are being cancelled. So last weekend was probably the last chance to drive for a while...
A few laps from last weekend. The car tended to wash out in turn 10, 1:29 was the best I managed. I think with proper front camber and a bit more rear grip I can knock that down a few more seconds.
Nice and smooth which may mean you can go faster, some good corner anticipation too.
A few laps from last weekend. The car tended to wash out in turn 10, 1:29 was the best I managed.
I ran a 1.28.5 with my Z. Looks like we drive a very similar way. But I still had the vlsd on mine. Need to feel it with my tomei.
Turn 10 feels like I am floating too. I don't believe front camber will change that since we are loading the rear more. I believe it is more related to wheel rate ratio and lack of downforce.
I did ran it once at 85mph on apex and it was too scary but I did nailed the turn in. 80mph seemed more stable and comfortable.
Turn 4 is the "have *****" turn. Most of the day I was lifting the throttle to balance the car at turn in. At the end of the day I was able to run it flat out but it really test your courage.
My Audi on 225 Conti slicks has better grip in 10 than the Z does on 275s, which is why I'm thinking lack of camber might be a factor here. Could be lack of downforce too, the Audi did have a fairly large splitter up front, might need to add something like that to the Z if the camber adjustment doesn't help.
Yeah, I was leaving a lot of time on the table because the rear felt loose and would step out if I pushed harder, which didn't inspire confidence. You can see that in the carousel on the last lap. I decided to go in and check the tire temps, but they were ok in the high 30s, so the oversteer is not tire related. Removing the rear sway should give me a bit more grip to push harder.
Turn 4 did bite hard last weekend, we lost two cars into the tire wall during Sunday wet sessions, including a buddy of mine. Both cars were banged up pretty good, one hit the wall with the driver's side, the other with the pass side. but both were driveable home. He'll have a stiff neck for a few days, but likewise is ok.
Placed an order for Z1 adjustable front control arms with spherical race bushings. They are out of stock right now, but I have a feeling I'll have plenty of time to get and install them before another event is available.
voodoo13 fronts are on back order as well. Was curious what spring rate you are running in the back? Wondering if a softer spring would help you plant more traction than removing the sway bar that would make the car more prone to understeer. There has been a few people on here that preferred running no rear, if i recall correctly said that it helped the rear wheels keep traction more independant from each other. Suppose driving style and handling may be more driver choice but thought i would give you something to think about.
I'm running 14k front and 10k rear springs with true coilover configuration. Is it too stiff? Maybe... I figured I'd try no sway bar first to see how that feels, I do feel like I just need a bit more grip back there to be happy. If removing the sway bar doesn't have the effect I'm after I'll get softer springs installed and try again. It's fairly inexpensive swap so no big deal either way. I just wish I had more chances to try it out coming up.
10k without aero for the rear more than likely will be too high. When going from divorced to true style, spring rate should drop. One reason I went with the bc racing ds instead of the br. 10k front/5k rear. Since i didn't have aero figured this would be a great starting point. With you running a 14k front, 7k would probably help alot. There are several threads on here where i got this info from. Just wish i remembered which ones they were to point you to them. I did want to go with fortune auto but would have cost considerable more money since i would have wanted swift springs as well. Plus i liked the idea of just buying replacement dampers if needed instead of sending in for revalving when they need servicing, especially since my z is a daily as well.
I managed to break off the helmet mount for my chatterbox, so I created and 3D printed new one. If anyone is still using the older chatterbox design, you can download the mount from thingiverse here
It's weird having all this downtime in the middle of spring. I've been accumulating parts, about ready to start slapping them on the car. First, a duckbill spoiler. I was planning to leave it urethane black, but the finish on it is not the greatest, so now it'll get painted matching silver being going on the car.
Also a set of Z1 adjustable fucas with race bushings
I also have a new set of XP8 pads to go on the rear and I still need to remove the rear sway bar and swap the pass seat base. And a replacement control module to try to fix the turn signal problem.
