DerHase's 2019 GTI Rabbit Edition: HPDE shenanigans

[DerHase]

So I finally got around to dropping the subframe out do change out the LCA bushings + finally install the 26mm H&R front sway bar...



Used a ball joint press to push the forward LCA bushings out...



Which promptly got stuck inside the tool... was able to hammer it out without issue. It screws up the bushing in the process but that's not a big deal in this case. Definitely a quick and easy way to remove them though...



Pressed the RS3 bushings in as well thanks to @scrllock !




Old vs new:




And about to go back in.

 

[DerHase]

Also I spontaneously purchased an aluminum MK8R/S3 subframe today. It came up for sale locally and ended up scoring it for $375.... Unfortunately the aluminum subframe requires longer bolts for the LCAs, and no local dealers have anything in stock. Also missing 2 of the 4 "mounting plates as seen in the one photo.

I just wanted the car back together so I will order all the needed hardware and do this all over again either after February or next winter. Maybe I'll decide to do sphericals or something silly before then.

No pics but I DID get the car back together and drove it around some this evening. It definitely doesn't suck. The car stays flat and doesn't feel like it's leaning over onto the outside front tire like before.

About to be on vacation for the next 5 days, then will be taking it to get a proper alignment next Friday.

After that I have some Endless 650 brake fluid to flush through the system (plus swap my track pads back on), mount my new V730s finally, and do an oil/filter change and I should be good to go for Feb 11/12!

I did decide to throw both sub frames (bare with nothing but the OEM pendulum bushings installed) on a scale to compare. Also measured both subframes and all dimensions are within 1mm of each other so no geometry changes etc. This was mostly already known but I like to confirm stuff for myself.

 

[tigeo]

It definitely doesn't suck. The car stays flat and doesn't feel like it's leaning over onto the outside front tire like before.

This was my impression as well after my FSB upgrade - the car was much flatter than with just the upgraded RSB.

Same location on track (Oak Tree @ VIR) but slightly different camera angle.

 

[DerHase]

Drove 14hrs back from Florida (in my truck, not the GTI) last night in time to take the car for an alignment this afternoon. Looks like I managed to get the subframe centered about as good as one can hope for when it comes to eyeballing it.

Going to wash it tomorrow, swap the V730s on, and put it back in the air for the track pads to be swapped back on, and bleed the brakes.

I decided I'd try something a bit different this time and got some Endless 650 fluid. The Motul 600 has never been a *problem* except on my very first HPDE (had to bleed after first session as the pedal sank - I chalked it up to an air bubble in the ABS module that got released when engaged on track)... BUT something I have noticed the past several events is after multiple HARD laps on day 1, the pedal would get just a BIT lower. Like maybe 1/8 to 1/4in lower before it initially engages. I never degraded beyond this point, but it's something I just didn't really like. This brake fluid is basically a test to see if the fluid is the cause of it or if there may be something else going on. FWIW I have read some others having a similar problem with Motul 600 and it being fixed after switching to something else. I still wouldn't hesitate to run Motul again... It was between Endless 650 and Castrol SRF... I chose the Endless because it comes in metal bottles (which preserves freshness considerably longer).

 

[Triple B]

I'd like to put the Alu subframe on mine - I was interested to see if the Mk8 version would fit, I'm sure its enhanced in some way (weight/stiffness) over the Mk7 Alu subframe that was on the GTI CSS/S3

 

[DerHase]

Everything is otherwise identical. While I didn't transfer everything over, I took tape measures to everywhere possible and verified they're dimensionally identical. One of the guys in the OS Discord has a MK8 subframe on his MK7.5 GTI as well. If he hadn't already confirmed it I wouldn't have taken a near $400 gamble on "hoping" it fits.

I will probably throw it on between February and May events... but I'm trying to get my hands on some other MK8 goodies first to do it all at once...

 

[DerHase]

Oil and filter changed
Pads swapped back to DS3.12/1.11
Brakes bled with Endless 650

Just need to mount the new tires, and make some VCDS tweaks I've been meaning to do (XDS full off mainly).

 

[scrllock]

How's the pedal feel with 650?

 

[DerHase]

How's the pedal feel with 650?

I don't have the wheels back on just yet so hard to judge. Got some stuff to do today but will be mounting the tires later and should be able to take it for a spin.
Honestly I don't expect to notice a difference until it's on track. The Motul would get a tad "soft" after the first hard session but then stay that way the rest of the weekend without issue.

I've also seen some chatter on the FB groups about bleeding in the "normal" order works better. So I did that this time. No pressure bleeders or anything, normal pumping method. Realistically speaking I don't expect there to be any difference since there's not AIR I'm trying to get out... just flushing old fluid for new.

It's been below freezing the last few days so was putting off mounting the tires until temps came back up. The Kumhos have been stored in our dining room for a month or so now.

I'm hoping these V730s don't need much of a real "scrub in" to grip well aside from a session or two... because it's not going to get anything worthwhile before the event.

edit: I will say I fucking hate pouring the fluid from the metal 650 canister - shit wants to dribble down the side of the bottle... which is made harder because you can't pour quickly otherwise the MC will overflow. Taking a paper towel or two and ripping a small hole in it, and slipping over the MC reservoir is a fantastic way to catch anything that spills though. Better than stuffing things all around it.

 

[scrllock]

I don't have the wheels back on just yet so hard to judge. Got some stuff to do today but will be mounting the tires later and should be able to take it for a spin.
Honestly I don't expect to notice a difference until it's on track. The Motul would get a tad "soft" after the first hard session but then stay that way the rest of the weekend without issue.

I've also seen some chatter on the FB groups about bleeding in the "normal" order works better. So I did that this time. No pressure bleeders or anything, normal pumping method. Realistically speaking I don't expect there to be any difference since there's not AIR I'm trying to get out... just flushing old fluid for new.

It's been below freezing the last few days so was putting off mounting the tires until temps came back up. The Kumhos have been stored in our dining room for a month or so now.

I'm hoping these V730s don't need much of a real "scrub in" to grip well aside from a session or two... because it's not going to get anything worthwhile before the event.

edit: I will say I fucking hate pouring the fluid from the metal 650 canister - shit wants to dribble down the side of the bottle... which is made harder because you can't pour quickly otherwise the MC will overflow. Taking a paper towel or two and ripping a small hole in it, and slipping over the MC reservoir is a fantastic way to catch anything that spills though. Better than stuffing things all around it.

I saw that thread, I also wouldn't expect much difference, but there's a lot of bad info in there, par for the course for mechanical advice on FB. I'm going to continue following the service manual method, which has served me well. That's all I'll say

I've heard that the feel is noticeably firmer even at a stop on the RF650, but spilling any of it is like pouring money on the floor.

 

[Autobahn]

I’ve been using RF650 for years, quality product at a good price. I felt a difference coming from ATE Type 200. Torque Racing Brake Fluid did a comparison on their site years ago with their fluid and RF650 that showed some good stats around the compressibility. I found info that a lot of race teams use it (GT3 Cup, F1, etc) too.

When I bleed my brakes I’m able to get firm engagement in the first 1/8 pedal travel. Inspires confidence braking at high speed to a slow turn.

Looking forward to hearing what your experience is like

 

[DerHase]

@scrllock pedal is great. Honestly not sure if it's "firmer" than Motul 600 (when new), but maybe. Definitely way better than 2mo and 2 days on track Motul though.

I wasn't happy with it at first so rebled again in the VW specific order. Coincidence? No idea. But will be doing the OE order from here out.

Made it to VIR. Been a hell of a last 2 weeks... Had some medical issues 2 Sundays ago which led to a fractured toe which is still healing. So DSG FTW. Saturday should be perfect, Sunday will be wet to say the least.

I cobbled together a Helix bypass harness so I could leave the heavy sub/amp at home last minute today, and added the Catalyst clip from Thing 3 Racing to keep it actively retained. The Garmin is pricy so don't want to risk it popping loose of the magnetic base. It IS very strong, but it only takes one good curb hit.

 

[DerHase]

Had a GREAT time at VIR (as always).

Set a new personal best 2:14.97 on Saturday:

Ran in the rain on Sunday which was a lot of fun:

And nearly shit myself in the second session... audio removed because of nothing but expletives and screaming like a bitch :

Was a lot of fun hanging with @tigeo and meeting @19birel in person. He did really damn well for his first time at VIR/first time on track.



As far as changes to the car go this time and my thoughts:
- 8 Bit Performance tune: Fantastic. No issues with overheating (I believe 255 maybe 260F was the most I saw all day on oil temps). +10mph or so vs stock... perfect.
- LCA bushings (solid rubber TTRS rear and Superpro poly front): Probably help but it's subtle.
- Kumho V730s: I friggin hate them. They got greasy super quickly every session. I'd get maybe one hard lap in and they're pushing because they're just done. They were *fun* to drive on, they squeal a lot to tell you when they're angry, etc. In the rain they suck if it's standing water. I drove 55-60mph the whole way home in the rain Sunday. Probably won't be buying them again, despite the good price. I think I'm going to buy some Michelins or Conti ECS for my stock wheels specifically for rain + street driving. But the below also needs to be factored in:
- 26mm H&R FSB (paired with 26mm RSB): Fantastic. Did not make the car a pushy mess, at least not on the first couple laps each session. I do wonder if perhaps the additional front rate was putting too much heat into the outer front tire... Or it added enough grip due to now less camber loss that it's generating more heat in the outside front.
- Endless 650 brake fluid: Fixed my problem of the pedal sinking halfway through a session. Perhaps now that I could be harder on the brakes I'm also putting more heat in the front tires? I know after a cooldown lap, by the time I got back into paddock my front rotors were seeing a bit over 800F... meaning much higher in use. Rears were at 350F by then.

I will be looking at the data more in depth over the next week or so. I have some Simos Tools logs that hopefully I can get overlaid on video for reference.

I think I need more camber up front and that may give me the bit more bite I need to account for the front tires heating up.

I admittedly didn't look too far into tire pressures and just WAG'd it trying 33psi hot, then down to 31psi hot all around trying to get some grip. It seems these things like REALLY low pressures. A lot of people seem to run 27-29psi hot successfully... so perhaps I'll try that next time out.


I have a few more clips to upload some time later this week, have a bunch of other stuff going on so it'll get posted when I have free time.

Photos below are from Apex Pro Photo.

 

[19birel]

You were really flying out there!

That moment in the rain was a certified code brown moment though for sure! Glad you and the car made it out from that one unscathed!

 

[DerHase]

Here was a pretty funny scare as I was slowly pushing a bit harder into the upper esses. Just missed the turn in a bit, realized what happened as approaching the curb on the right at the wrong angle, so put the wheel straight once back on the ground to settle it back down.

Also here's a neat comparison of the 26mm H&R FSB (on soft setting) + 26mm H&R RSB vs the stock 24mm FSB + 26mm. @Mini7