ChrisD63

This past weekend I went to Englishtown Raceway in NJ to participate in a track event with instructors. After a few sessions they let us go alone and we all had a blast! The C63 did way better than I thought it would and it surprised many people out there that day. The issue I ran into was my tires just couldn't keep up. Towards the last few sessions, my front tires began loosing grip and the car was understeering like crazy. My current tire setup is 245/265 on OEM rims. Tires are Michelin Pilot SuperSports which are great tires but definitely not the right tires to be pushing hard on the track. The other issue I ran into was major fade from the brakes after just a few laps (Stock rotors, Stock rear pads, Stoptech front pads).

I am looking to run a dedicated race setup on my OEM rims. Any recommendations as far as tire brand/sizes? I am addicted to road racing after just my first time out! I've run my car in the 1/4 mile many times but nothing comes close to the satisfaction you get from road racing. If you haven't tried it yet, I highly recommend that you do.

What I did find interesting is that when I switched cars with my friend who has a 2012 P31 C63 Coupe, I found that my 2009 C63 Sedan (Non-P30) was way more balanced and more fun to drive with no major mods; just springs, a strut bar, tune, exhaust and filters.

I've attached some photos for your viewing pleasure.

Clark Kent

You and I have similar set ups: PSS's, 245/265, tune, etc and I have similar results at the track. To help reduce brake fade I turn stability control off. That way as I drive hard the car isn't trying to reign me by autonomously applying the brakes. Less heat build up and therefore longer lasting brake feel.

I too enjoy the shock and surprise of the other drivers as a 4 door family sedan catches and passes them!

natman316

Chris, if you want to track on PSS I recommend you use the 19s, much better feel imo because of the thinner sidewall. The PSS has a soft sidewall, so on 18s it feels pretty wobbly. That said If you want to run a dedicated set of racing tires, it will out perform the PSS easy for sure. As for brakes, did you flush the braking system before you went? Fresh brake fluid will greatly help to reduce the brake fade, more so than upgrading the rest of your braking system. Turning T/C off help with the brakes too, but I like to keep it in sport so that it saves my *** if I mess up haha.

We should get some north east AMG guys together for a track day!!

ChrisD63

I turn traction control on sport when I'm on the track but how do you turn stability control off? Is there a different method?

ChrisD63

I had my brake fluid changed not too long ago but it's not race fluid so I guess it overheats on the track. Interesting thought regarding the 19s vs. 18s. I would try my 19s but they are fresh PSS and I don't want to ruin them like I did to my 18s after one track day. I heard the AMG group of northeast is thinking about putting together a track day at NJMP so that would be something to look forward to!

natman316

I always flush my brakes the day before going so that the fluid doesnt absorb any moisture at all before the track day. Haha iI feel you with the tires but I did put 3 track days and a tonne of hard driving burnouts etc on them and nearly 10k on them I think, still have "some" tread left lol Probably could get another slidely track day out of them.

I'd be down for NJMP, that track looks very good.

zcct04

The track tires tend to have a stiffer sidewall so 'wobbly' wont be an issue with a better tire. My limited experience says that the 19s will improve the 'feel' a bit but that you're better off staying with the lighter-weight 18s for improved performance on the track.

Anyone with lotsa track experience able to share their experience on 18s vs 19s?

Dogtag114

I wrote off this track as too small to realize any speed... What is the fastest you can hit here? I hit Lime Rock for AMG Academy last fall and am going advanced next week in Palm Beach...

If I was wrong on Englishtown, I'll have to check it out.

ChrisD63

Englishtown is mediocre at best.. On the straight we were hitting about 100mph but it is a very poorly maintained track with many potholes and uneven surfaces. My next track session will be at either NJMP or Poconos Raceway.

Clark Kent

I suspect we are using different terminology to refer to the same thing. To turn ESC off, press and hold the 'traction control' button until 'ESC OFF' shows on the display.

You have now activated 'death mode'. Be careful.

From the pic of you on the track it looks like the pavement surface is extremely rough - and the pic of your tires seems to support that. The three tracks I've been on are not like that at all and do not chew up our expensive tires to such a degree.

I use Motul 600 racing brake fluid. There's also a 660 out there with an even higher boiling point. I have been fine with the 600.

Did you guys see my earlier thread/video of my day at the Circuit Of The Americas in Austin TX? Smooth as glass. It's like playing golf at Pebble Beach or Augusta! Can't wait to go back next year. The first 2 1/2 minutes is the warm up lap then once we hit the front straight it's full speed ahead:

ChrisD63

You are correct, the track was extremely rough and unpredictable. Now it makes sense as to why my front tires became like that. As for the Motul brake fluid, how much do you guys usually pay to have the fluid flushed and changed? Is it okay to run the racing brake fluid on the street after a track day? Great driving by the way!

Clark Kent

About $115 for me - and I supply the fluid.

I do (now). I used to change it out right after each event but I asked to inspect the fluid one time. Both myself and the tech estimated the fluid ought to be changed after every third track day. Meanwhile, I have zero brake loss on the street.

Thanks! That is the best track I have ever been on and will ever be on (it is the only Formula 1 rated track in the US). I study that video and I see TONS of room for improvement though. But I like the parts where I pass multiple M3's on the same straight :-)

natman316

I use a mityvac pump and DIY. Mityvac was 56 bucks. +1 to motul600

ChrisD63

I actually have a Mityvac and used it for a few oil changes. It didn't even cross my mind to use it for the fluid change. Is there a DIY on Mbworld? How much fluid is necessary and where do you guys get the race fluid from?

natman316

Not mityvac sorry, its called motive power bleeder. Specifically for brakes. There is a DIY i think but it also comes with instructions.

Fluid i order online.

Mort

I use the Motive Brake Bleeder as well and it does a great job. Makes it an easy one man job.

ChrisD63

Do you need to bleed any brake lines or is it a simple process where you pump out the fluid and refill it?

Mort

You will need to bleed the brakes at the calipers with the car jacked up and remove the wheels or on a hoist and remove the wheels. I siphon the fluid out of the reservoir and refill it with fresh fluid, attach the bleeder and crack the bleeder screws starting from the furthest to the closest to the master cylinder.

jcfay

Yup, I bet COTA is probably one of the best in the US since it's brand spankin' new and also for formula 1. I'd love to lap there. That's awesome. Since I'm in NJ too any other votes for top tracks in this (or other) areas? I'm sure there are a bunch that aren't gnarly?

natman316

NJMP looks good, never lapped there tho so not sure. I also like summit point but I guess a little far from NJ. Planning to go there at the end of may though if anyone is interested

Diabolis

Brake fade is different from a spongy pedal. The first is a function of pad/rotor friction, the second due to boiling the brake fluid. Yes, you should always flush the brake fluid before a track event, but brake pads that get too hot will definitely fade after a lap or so even if you're running fresh Motul 600, ATE Super Blue or another higher boiling-point brake fluid.

I got a set of 18" Toyo R888s for track duty. Considerably better grip than street rubber once they warm up, but being R-comp they don't give you nearly as much warning at the limit (although they seemed better than other R-comps I've run).

Pic 3 shows you're rolling on the sidewall - almost unavoidable in a heavy car like the C63, but tires with a stiffer sidewall and/or perhaps a little more air could help that.

ChrisD63

Thanks for the response. I guess I would consider it more of a spongy feeling rather than fade now that you mention it. I did lower the tire pressure because it got close to 55psi when warm. Maybe I lowered it a bit too much. What are the sizes of the r888s you're running?

Diabolis

I bought a set in the OEM 235/40-18 and 255/35-18 sizes to put on the OEM 18" rims. Did only one track day last fall. Initial impressions were pretty good. I drove to the track on them so no street tire baseline but I suspect they are easily 4 seconds per lap faster than the best street tires around Mosport. Car still tends to understeer in the slower corners so if anything you need more rubber on the front, and there was only one corner where I could break the rear end loose if I hammered on the throttle. IIRC I ended up running 39 psi F and 36 R without rolling on the sidewalls. LF tire took the most punishment due to track layout but still have approx. 4/32 tread (6/32 new unshaved).

OEM P31 brakes were absolutely fine with no fade or mushy pedal at all for the whole day on fresh ATE Super Blue.

ChrisD63

Do you think we can go 255s up front on oem wheels? I think that would help a lot considering how heavy the front end of our cars are.

Diabolis

I highly doubt it. You may be able to physically mount a 255 tire on an 8" rim, but I suspect that the excessive sidewall flexing you'd get would be more detrimental (if not outright dangerous) than the marginally increased traction you'd get from the slightly larger contact patch.

You can squeeze in a 255 on the front (I just ordered wider outer barrels for my 3-piece wheels to do exactly this), but you'd need a 9" wide rim with the proper offset.