Track forum general chit chat.

[roastbeef]

Originally Posted by okusa

In case anyone's interested...selling my Trailex trailer

https://www.m3post.com/forums/showthread.php?t=2082602

That’s a nice setup. If I could sell my alums in time, I’d pick this up.

[jmeenach]

Quick question for everyone:

I was out at Willow Springs last weekend for SV and I had consistent instability under braking coming into turn 9. I tried braking earlier/lighter, trail braking, and braking in a straight line, but nothing I tried seemed to make it go away. I did not experience any real instability in turn 1, which I would consider to be the only other high speed braking zone (I don't brake coming into 2 or 8).

Car is set up on KW clubsport 2-way, with 2.6 deg camber f, 2.3 r, 0 toe up front, with minimal toe-in in back.

Candidly not sure if this is a setup issue or operator issue? Would love to hear from others to see if they've experienced similar feeling?

[omgzirra_exe]

Originally Posted by jmeenach

Quick question for everyone:

I was out at Willow Springs last weekend for SV and I had consistent instability under braking coming into turn 9. I tried braking earlier/lighter, trail braking, and braking in a straight line, but nothing I tried seemed to make it go away. I did not experience any real instability in turn 1, which I would consider to be the only other high speed braking zone (I don't brake coming into 2 or 8).

Car is set up on KW clubsport 2-way, with 2.6 deg camber f, 2.3 r, 0 toe up front, with minimal toe-in out back.

Candidly not sure if this is a setup issue or operator issue? Would love to hear from others to see if they've experienced similar feeling?

what brake pads were you using? tires? have you inspected all your bushings?

you've left quiet bit of information out, so i'm only guessing what to ask next.

[roastbeef]

Originally Posted by jmeenach

Quick question for everyone:

I was out at Willow Springs last weekend for SV and I had consistent instability under braking coming into turn 9. I tried braking earlier/lighter, trail braking, and braking in a straight line, but nothing I tried seemed to make it go away. I did not experience any real instability in turn 1, which I would consider to be the only other high speed braking zone (I don't brake coming into 2 or 8).

Car is set up on KW clubsport 2-way, with 2.6 deg camber f, 2.3 r, 0 toe up front, with minimal toe-in out back.

Candidly not sure if this is a setup issue or operator issue? Would love to hear from others to see if they've experienced similar feeling?

Didn’t feel like the rear wanted to step out towards the edge of the track?
Mine does that too.

[jmeenach]

Originally Posted by omgzirra_exe

what brake pads were you using? tires? have you inspected all your bushings?

you've left quiet bit of information out, so i'm only guessing what to ask next.

Yeah, I kind of realized once I saw your response. OEM rotor and calipers, stainless lines, upgraded fluid, and Endless ME20 pads all around. Rotors, pads, and fluid have three track days and 500 street miles, but this is my first time at WS with this setup. I don't recall having this much difficulty with getting the car settled last time at this track, but that was almost a year ago and I'm also lapping around 7 seconds faster than last time, so my entry speed differs from before as well.

Tires are Michelin Cup 2, 255/35r19 F and 275/25r19 rear with 12 heat cycles on them (before anyone chimes in about these tires sucking... I just ordered Apex 18x10's and will be changing to RE71RS 275/35r18).

Bushings were inspected a few months ago by my local mechanic and everything seemed to be in order. That said, I do still have the OEM rear subframe bushings, which I have also heard can cause movement in the rear. I've considered going with solid rear, but haven't gotten around to it yet.

Because of perch position with the KW clubsports on the OEM 359 wheel, I have to run a 10mm spacer up front to clear. I tried a 5mm before and still had some contact from the tire in hard cornering situations.

Also - no aero on the car.

Originally Posted by roastbeef

Didn’t feel like the rear wanted to step out towards the edge of the track?
Mine does that too.

Initially yes, but it's not a consistent step out to the left. The rear will gain a rhythm back and forth before settling down as I initiate more steering in toward the apex. I've tried my best to keep soft hands to allow the car to settle more naturally as opposed to really fighting it.

I also drove my friend's stock 991.2 3rs for a quick session and his car did not even hint at instability coming into 9. I realize we're talking two entirely different leagues of car, especially considering the factory rear aero, but the delta in stability in that corner was a little unnerving.

[omgzirra_exe]

Originally Posted by jmeenach

Yeah, I kind of realized once I saw your response. OEM rotor and calipers, stainless lines, upgraded fluid, and Endless ME20 pads all around.

i think the rear toe out in what causing your instability..im currently at .21 total toe in for the rear.

hopefully someone else who is more qualified is able to confirm my thought..

edit: i thought he said toe out. my bad.

[danvitmon]

Originally Posted by omgzirra_exe

i think the rear toe out is what causing your instability..im currently at .21 total toe in for the rear.

hopefully someone else who is more qualified is able to confirm my thought..

did you mean to put toe in? He said he has minimal toe in at the rear, whats minimal? Usually on street cars we like to do 1/16-1/8th" toe in at the rear and 0 toe up front if you put a lot of street miles on it. You can add 1/16th toe out at the front to improve turn in response.

FWIW, I am at -3.8 1/16th toe out Front, -2.3 1/8th toe in Rear.

[omgzirra_exe]

Originally Posted by danvitmon

did you mean to put toe in? He said he has minimal toe in at the rear, whats minimal? Usually on street cars we like to do 1/16-1/8th" toe in at the rear and 0 toe up front if you put a lot of street miles on it. You can add 1/16th toe out at the front to improve turn in response.

FWIW, I am at -3.8 1/16th toe out Front, -2.3 1/8th toe in Rear.

yeah my bad LOL

[tsk94]

More rear toe in would be my first suggestion.
If you have stock rear subframe bushing that could be playing a role as well. Upgrading those makes a noticeable difference in rear end stability.

[jmeenach]

Originally Posted by danvitmon

did you mean to put toe in? He said he has minimal toe in at the rear, whats minimal? Usually on street cars we like to do 1/16-1/8th" toe in at the rear and 0 toe up front if you put a lot of street miles on it. You can add 1/16th toe out at the front to improve turn in response.

FWIW, I am at -3.8 1/16th toe out Front, -2.3 1/8th toe in Rear.

IIRC, I have 1/16th toe-in rear. At the time, I had asked for a track/street balance because I only drove 4ish track days per year. I already have three days this year and plan to track more often, so it sounds like I should consider a more track-focused setup.

With a slight toe-out up front, will the car wander on the street? While I will be spending more time on track, it'll still see double duty for another six months or so.

Originally Posted by omgzirra_exe

yeah my bad LOL

All good man!! haha

Originally Posted by tsk94

More rear toe in would be my first suggestion.
If you have stock rear subframe bushing that could be playing a role as well. Upgrading those makes a noticeable difference in rear end stability.

Thanks, it seems the general consensus is to add more toe-in rear. I'll look into solid rear subframe upgrade if alignment doesn't make a noticeable improvement.

[amg6975]

Front tension arms can also cause a lot of rear instability. Going spherical in those helped my car immensely with the booty shaking under braking.

[berns]

That's the hardest turn on the track. It's nothing like braking for T1. T9 you've just sustained triple digits through a massive, bumpy sweeper, and there's really no straight kind of braking for T9 unless you time it perfectly, and even then, you're off the brakes and straight into more triple digit turning, so you're feeling everything. You need to be gentle there because you have a ton of weight transfer that wants to send you to the dirt.

It's a heavy E92 too, on too little tire, with soft dampers and no aero, so all the bad qualities of that braking zone are going to be accentuated.

As tsk94 said, this could be bushing/arm related. With all the mushy stock bits, the rear end can tend to walk around under high loads. Sounds like there are some changes you could make to both inputs and parts/setup to get you feeling better.

An in-car video would also be super helpful so we can actually see what's happening.
For reference, here's a lap in my car from the same day. Even as I warmed up to the track I felt sketched out about braking at T9.

[1FastSicilian]

Does anyone have an DIY for a do88 oil cooler?

Is it straight forward replacement or do i have to do any cutting/trimming? I saw that with the DCT cooler, you need to trim IIRC

[danvitmon]

Originally Posted by 1FastSicilian

Does anyone have an DIY for a do88 oil cooler?

Is it straight forward replacement or do i have to do any cutting/trimming? I saw that with the DCT cooler, you need to trim IIRC

check their install guide. do88 has some of the most in depth guides I have read. IIRC I had to trim the plastic air guide the cooler is housed in a bit with just some pliers/cutters and a dremel. Otherwise straightforward

[1FastSicilian]

Originally Posted by danvitmon

check their install guide. do88 has some of the most in depth guides I have read. IIRC I had to trim the plastic air guide the cooler is housed in a bit with just some pliers/cutters and a dremel. Otherwise straightforward

Thank you! I haven’t even opened the box yet so I’ll check that out. Plan on tackling this in the upcoming week or two

[omgzirra_exe]

Originally Posted by 1FastSicilian

Thank you! I haven’t even opened the box yet so I’ll check that out. Plan on tackling this in the upcoming week or two

the only thing you might have to look out for is the CF duct when installing to the cooler as i think kolosy had a fitment issue?

[jmeenach]

Originally Posted by berns

That's the hardest turn on the track. It's nothing like braking for T1. T9 you've just sustained triple digits through a massive, bumpy sweeper, and there's really no straight kind of braking for T9 unless you time it perfectly, and even then, you're off the brakes and straight into more triple digit turning, so you're feeling everything. You need to be gentle there because you have a ton of weight transfer that wants to send you to the dirt.

It's a heavy E92 too, on too little tire, with soft dampers and no aero, so all the bad qualities of that braking zone are going to be accentuated.

As tsk94 said, this could be bushing/arm related. With all the mushy stock bits, the rear end can tend to walk around under high loads. Sounds like there are some changes you could make to both inputs and parts/setup to get you feeling better.

An in-car video would also be super helpful so we can actually see what's happening.
For reference, here's a lap in my car from the same day. Even as I warmed up to the track I felt sketched out about braking at T9.

First of all, I love watching your videos and I've really enjoyed watching your build progress. You're actually one of my inspirations for wanting to gain more track experience and get this car dialed in (I really want to run in Bimmer Challenge B3).

My new tires/wheels should arrive next week, so that should resolve the lack of sidewall issue that you have mentioned. Once those are installed on the car, I will be sending the car to West End Alignment for alignment and ride height adjustment to address some of the setup. I guess the only decision I need to make is whether I should install the solid rear frame mount now or see if there is improvement with these changes. I'm leaning toward ordering the solid mounts now, so I don't need to worry about alignment changes that could result from dropping the rear subframe.

From that point, I should know pretty quickly whether that has resolved the issue, or if I need a driver mod and am making steering/braking input that is making the experience worse. I haven't ever run with an in-car camera, but I'll change that shortly as well, so I can review in-car footage and see where I can improve my driving.

[Bartledoo]

While snooping around, make sure your sway bar end links are tight on both ends of the links.

[1FastSicilian]

Where are you guys mounting your external res. for your coilovers..

Looks like the only good place is on the cowl

[Richbot]

I tucked mine into the windshield drain with some fuel cell foam to hold them in place. Kept them cooler than some of the engine bay options would allow

[1FastSicilian]

Originally Posted by Richbot

I tucked mine into the windshield drain with some fuel cell foam to hold them in place. Kept them cooler than some of the engine bay options would allow

I can’t fit mine there bc if the hinges on the 2013.

[alpine2530]

Replacing the oem clutch soon. With the car being an 08’, looks like I’ll have to replace the flywheel. Car is being used on track with about 5-10 track days a year, possibly even more. Getting addicted to this. Suggestions on an aftermarket setup? Or keep it oem, updated DMF and clutch? Car isn’t a daily. More of a weekend / track toy.