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      07-03-2020, 07:46 AM   #67
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Quote:
Originally Posted by fanatic1 View Post
Tips look quite different from MPE with Ti tips
GTS tips are welded on single wall tips, just like the tips on your original CS exhaust. GTS tips are titanium while CS tips are stainless steel though.
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      07-03-2020, 06:38 PM   #68
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Track day on 7/2/2020. Car turned over 2k miles while on the track, and I've logged just under 500 miles at the track. Looking back, I bought the car with the intention of driving it as a daily, but I really hate driving it on the street now. Not because of the car, it's amazing. Mostly because speed limits are comically low and even though I mostly drive it in canyons, 65mph in a 45mph is just not exciting compared to the track. On the plus side I find myself actually looking at the scenery more frequently because you quickly catch traffic and then crawl at 35mph in a 45mph.

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Only photo I took at the track, after loading the car onto the trailer. I never thought a set of taillights would be so beautiful.

Found a way to route my microphone cable into the cabin. There are some serious gaps around the cage and the rear seat blanks. Now I can turn on the GoPro + microphone while in the car. No more excuses of no audio.

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      07-03-2020, 07:24 PM   #69
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Now for the bitching, whinging, and moaning. I brought the 3.5 year old Cup 2s on the OEM wheels along with 18x10/18x11 EC-7 with used unknown heat-cycle NT01s in 275/305. The NT01s read 5/32" of tread, so I figured they didn't have a lot of cycles on them. I've already put ~150 miles on them with maybe 1/32" of wear.

I started the day on the Cup 2s, and after reviewing some gifted notes on the track I tested the curbing. Since the resurfacing the curbing is now very usable. I then set pressures on the Cup 2s and went out to set a personal best. 2:01.6 came with ease, along with a string of 2:02s. I'm currently completely throwing away turns 1 and 4, they both spook me with the NT01s constantly rotating the car, so with the Cup 2s I just took casual ~10mph slower entries.

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Now the good news, with the Cup 2 I'm completely running over the curbing at T5, T9b, T13, and T15. I'm coming out of the corkscrew so god damn fast and the Cup 2s are just hooking so well. I'm WOT from T13 all the way to the straight with a lift for T14, completely driving over T15 with barely a hiccup. T9b is a similar case, to the point where a few times I nearly lost the car in T10 because I mistimed the braking. This was also the first time where I started using the throttle to really rotate the car in T2 and T11. Michelin makes good rubber, I'm really impressed with this stuff.

Now for the complaining. I'm not sure if my rear NT01s are toast, but they remind me of driving on hot 300-treadwear all-season trash during a Lemons race where someone oiled down the track with their improvised oil cooler that they cobbled together while drunk the night before. Maybe my pressures are off. Maybe the suspension is off. All I know is T12, a rising crest gentle left which I hit at full throttle with a 3-4 shift ~2 car lengths after the apex, the rear-end with the NT01s under WOT will come around 10 out of 10 times before the shift. The Cup 2s, no problem. I'm WOT from T11 apex to braking for T13, easily going into T13 fast enough that once again I messed up braking several times.

T7 is the same case. This is an uphill decently cambered sweeper, I enter around 85mph, scrub~5-7mph to apex and then power to track-out up a hill. Cup 2s have no issue and I come screaming into T8 braking. NT01s I'm modulating the throttle ~1 car length past where I apex trying to get the rear to settle without coming around. Similar behavior in T9b, and the T13-T15 corkscrew. T13 is a complete bitch with the NT01s, I almost spun several times trying to take the lines I could manage with the Cup 2.

Now the confusing thing. The NT01s braking, turn-in, and mid-corner grip is stellar. It helps that they're wider than the Cup 2s, and the contact patch has less grooving. The tires were communicating well and up until I transition from zero/maintenance throttle to rolling into WOT, corners feel amazing. I then thought maybe I'm just cornering harder with the NT01 so post-apex I'm asking more of the rears than with the Cup 2s. Thanks to the HUD + GoPro I re-ran T12 repeatedly(~8 attempts) on the NT01 using my entry and apex speeds from footage with the Cup 2s. Each time the rear tried swinging around. What in the what.

There are a lot of variables, so it's really tough to make a judgement on the tires. With the NT01s the platform feels like a car with an overly tight rear sway, rolling 1/4 throttle to WOT anything less than 1 car-length after the apex yields horrific oversteer. The Cup 2 I can stomp the loud pedal like an idiot monkey and the rear just hooks and scoots while I bang on the door cackling with glee.

edit: I never broke 2:03 with the NT01, and I used 2/3rds of my time fighting these tires. If I wasn't worried about fender damage I'd just blow both tires in a glorious ear shattering burnout.
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      07-08-2020, 08:54 PM   #70
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Originally Posted by CanAutM3 View Post
GTS tips are welded on single wall tips, just like the tips on your original CS exhaust. GTS tips are titanium while CS tips are stainless steel though.
Sorry to hijack, but circling back to this. Understand standard CS exhaust, but MPE with Ti tips? What gives?
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      07-08-2020, 09:57 PM   #71
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Quote:
Originally Posted by fanatic1 View Post
Sorry to hijack, but circling back to this. Understand standard CS exhaust, but MPE with Ti tips? What gives?
No, M4CS and M4GTS have completely different exhaust systems entirely.

Part numbers do not match between the two models
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      07-08-2020, 10:02 PM   #72
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Originally Posted by Day Laborer View Post
No, M4CS and M4GTS have completely different exhaust systems entirely.

Part numbers do not match between the two models
Roger that, but optioned MPE with titanium tips - duped paying for Ti tips - and it wasn’t cheap

Moral of the story, welded single wall Ti GTS > MPE with Ti (dual wall) tips
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      07-09-2020, 03:31 AM   #73
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Quote:
Originally Posted by fanatic1 View Post
Sorry to hijack, but circling back to this. Understand standard CS exhaust, but MPE with Ti tips? What gives?
The concept of the exhaust tips is the same for the GTS and CS: single walled welded on tips (i.e. no tip finishers). These tips have a larger inner diameter, which alters the tone of the exhaust. The CS has stainless steel tips welded to the stainless steel "sport" rear section while the GTS has titanium tips welded to the titanium MPE rear section.
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      07-09-2020, 11:26 AM   #74
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Here's a clip on the Sport Cup 2 when I set a personal best at my home track. It's such a calm and low-key experience vs the NT01 runs.



Lowering the rear spring perch before my next track day to see how that impacts things with the NT01. I'm guessing that will also adjust the rear camber settings a bit more, perhaps aggravating my rear traction issues with the NT01 if excessive rear camber is the problem. Will see if I can squeeze in an alignment session, but I was planning on using a pyrometer to get some alignment feedback before my next alignment.
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      07-09-2020, 12:25 PM   #75
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Quote:
Originally Posted by CanAutM3 View Post
The concept of the exhaust tips is the same for the GTS and CS: single walled welded on tips (i.e. no tip finishers). These tips have a larger inner diameter, which alters the tone of the exhaust. The CS has stainless steel tips welded to the stainless steel "sport" rear section while the GTS has titanium tips welded to the titanium MPE rear section.
I believe he his just pointing out how the MPE Ti tips dont look anything like the GTS Ti tips in terms of colour. MPE Ti tips may be made of titanium but dont have that classic Ti shine to them.

My question is what is the price delta between Ti and Carbon MPE tips? If similar, Carbon is a no brainer. I love how mine look.
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      07-09-2020, 01:05 PM   #76
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Quote:
Originally Posted by Maitre_Absolut View Post
I believe he his just pointing out how the MPE Ti tips dont look anything like the GTS Ti tips in terms of colour. MPE Ti tips may be made of titanium but dont have that classic Ti shine to them.

My question is what is the price delta between Ti and Carbon MPE tips? If similar, Carbon is a no brainer. I love how mine look.
The MPE Ti tips being triple walled, the outside wall sees much less temperature and therefore wont see much discolouration. The inside of my MPE tips is completely blue though. I personally never liked discoloured exhaust tips, so I dont mind it too much, but I dont dislike the idea of the additional weight reduction of the simpler GTS tips .

As for the CF tips, they do command a fair premium over the Ti tips (~400CAD), since they are essentially the Ti tips with a CF sleeve riveted over them. I personally prefer the cleaner look of the Ti tips.
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      07-09-2020, 02:02 PM   #77
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Quote:
Originally Posted by Gomeler View Post
I'm coming out of the corkscrew so god damn fast and the Cup 2s are just hooking so well. IAll I know is T12, a rising crest gentle left which I hit at full throttle with a 3-4 shift ~2 car lengths after the apex, the rear-end with the NT01s under WOT will come around 10 out of 10 times before the shift. The Cup 2s, no problem. I'm WOT from T11 apex to braking for T13, easily going into T13 fast enough that once again I messed up braking several times.

then power to track-out up a hill. Cup 2s have no issue and I come screaming into T8 braking. NT01s I'm modulating the throttle ~1 car length past where I apex trying to get the rear to settle without coming around. Similar behavior in T9b, and the T13-T15 corkscrew.

Now the confusing thing. The NT01s braking, turn-in, and mid-corner grip is stellar. It helps that they're wider than the Cup 2s, and the contact patch has less grooving. The tires were communicating well and up until I transition from zero/maintenance throttle to rolling into WOT, corners feel amazing. I then thought maybe I'm just cornering harder with the NT01 so post-apex I'm asking more of the rears than with the Cup 2s. Thanks to the HUD + GoPro I re-ran T12 repeatedly(~8 attempts) on the NT01 using my entry and apex speeds from footage with the Cup 2s. Each time the rear tried swinging around. What in the what.

There are a lot of variables, so it's really tough to make a judgement on the tires. With the NT01s the platform feels like a car with an overly tight rear sway, rolling 1/4 throttle to WOT anything less than 1 car-length after the apex yields horrific oversteer. The Cup 2 I can stomp the loud pedal like an idiot monkey and the rear just hooks and scoots while I bang on the door cackling with glee.

edit: I never broke 2:03 with the NT01, and I used 2/3rds of my time fighting these tires. If I wasn't worried about fender damage I'd just blow both tires in a glorious ear shattering burnout.
Interesting feedback. I've isolated some of your commentary. Have a working theory on this based upon running 19's (305 section rear) and then going back to the OE diameter stagger. It's an unconventional view because so much emphasis is put on width.

I think there's something to the 20" rear, the shorter sidewall and longer contact patch that a. is more communicative, i.e., allows you to sense the available traction more readily/accurately and confidently get on the throttle, and b. actually helps put the power down.

Check out this article from C&D, specifically the "Growth" phase of a dragster tire where it balloons to 38" diameter https://www.caranddriver.com/feature...res-explainer/

The GTS needs help maximizing forward traction, not so much lateral. Along with the feel/communication factor, believe it's why they went with the rear 20". I don't think it's just for looks, as is often suspected. Where tire width is maximized, adding diameter augments the contact patch.

M is not alone in terms of large(r) diameter rear wheels on track-focused models (Porsche, Lambo, Corvette). G8X looks to be getting the staggered diameter and rear 20" too.

This is not to say one couldn't build an 18" setup that's faster, especially once slicks and revised suspension are involved (GT4 racecar). But in terms of all stock suspension elements, streetable tires, working with the car as engineered and constructed by M, I did not care for the 19" 275/305 setup as much as I like the stock stagger on track. If I get another lighter set of wheels at some point, believe I'll actually stick with OE M specs.

If you run through the Cup 2 and decide you might prefer the OE wheel specs, try a set of Supercar 3R. I think you'd really be convinced then. They're more durable, add sharpness and traction over star spec Cup 2.
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      07-09-2020, 03:38 PM   #78
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The NT01 is 26.42" tall, and the rear Cup 2 is 26.8" tall. I wager the NT01 is nearly an inch wider, likely yielding a larger static contact patch than the Cup 2. It's possible the NT01's larger sidewall is causing the contact patch to narrow a bit at speed, but I'm having these contact issues on corners between 45mph and 85mph. The unknown variable is the age/heat cycle of these NT01s. The behavior reminds me of heat cycle cooked(25+) R7s, just incredibly unpredictable.

I won't be tracking the OEM wheels anymore after the Cup 2s cord. I've got a real nasty ~1.5" long gouge from a rock in the barrel of one of the rears, and I don't want to beat them up anymore. I'll likely just put another set of Cup 2s on them, and use that for any street driving I do until they age out.

My wheel/tire plan for the year is as follows:

Grab another set of EC-7, and try mounting the NASA spec Toyo RR, 295/30r18, onto an 18x11 and seeing if that clearances the front fender liner. If so, run 18x11 square and rotate based on wear, optimizing use of the set. If not then find some front tire option, possibly still the 295/30r18 on an 18x10, and continue rotating sides based on wear. Judging from my cup 2s, this car is obliterating the fronts, which isn't surprising given its weight.

On the NT01 wheel/tire set I'll have to debate between the A052, or a weird combination of RE71Rs. Sadly the RE71R doesn't really have a good option for the 18x11 rear, I'm not sure if the 285/30r18 would be too much of a stretch, maybe the taller 275/35r18 would be a better choice. 18x10.5 squared would be ideal for the RE71R, and might be an option in the future. I'm not opposed to having 3 sets of track wheels, it's a minor inconvenience when loading the trailer and really opens up some options based on session goals.
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      07-09-2020, 03:49 PM   #79
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Roger that. I read your comments as experiencing exit/forward traction advantage w/ stock vs. 18's, not cornering.

What's the date code on those NT01s?

Look forward to seeing what alternative you find equal or better than OE. Useful that you have a PB OE Cup 2 reference.
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      07-09-2020, 05:12 PM   #80
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Quote:
Originally Posted by FormulaMMM View Post
Roger that. I read your comments as experiencing exit/forward traction advantage w/ stock vs. 18's, not cornering.
You're correct in my issue, post-apex grip on the NT01 has been garbage for me. Pre-apex the grip is on-par or better than the Cup 2.

Quote:
Originally Posted by FormulaMMM View Post
What's the date code on those NT01s?

Look forward to seeing what alternative you find equal or better than OE. Useful that you have a PB OE Cup 2 reference.
Well now I'm embarrassed. I know when I unpacked them I examined the fronts, and they were mid-2018s. I clearly didn't examine the rears outside of depth gauging them. Mid-2017 on the rears

Thanks for asking that question. Think I'll order a set of NT01s ASAP to give them a proper test. Under $1k for a set, and if they wear like the fronts have been wearing, they'll be great warm-up tires before swapping to something stickier.
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      07-09-2020, 06:37 PM   #81
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As for the CF tips, they do command a fair premium over the Ti tips (~400CAD), since they are essentially the Ti tips with a CF sleeve riveted over them. I personally prefer the cleaner look of the Ti tips.
The CF ones match the CF diffuser perfectly.

But I'll admit 1.2k for tips is M Tax at its finest. My first catback was ever (RSR on a RSX-S) was less than that lol
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      07-09-2020, 08:42 PM   #82
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Quote:
Originally Posted by Gomeler View Post
The NT01 is 26.42" tall, and the rear Cup 2 is 26.8" tall. I wager the NT01 is nearly an inch wider, likely yielding a larger static contact patch than the Cup 2. It's possible the NT01's larger sidewall is causing the contact patch to narrow a bit at speed, but I'm having these contact issues on corners between 45mph and 85mph. The unknown variable is the age/heat cycle of these NT01s. The behavior reminds me of heat cycle cooked(25+) R7s, just incredibly unpredictable.

I won't be tracking the OEM wheels anymore after the Cup 2s cord. I've got a real nasty ~1.5" long gouge from a rock in the barrel of one of the rears, and I don't want to beat them up anymore. I'll likely just put another set of Cup 2s on them, and use that for any street driving I do until they age out.

My wheel/tire plan for the year is as follows:

Grab another set of EC-7, and try mounting the NASA spec Toyo RR, 295/30r18, onto an 18x11 and seeing if that clearances the front fender liner. If so, run 18x11 square and rotate based on wear, optimizing use of the set. If not then find some front tire option, possibly still the 295/30r18 on an 18x10, and continue rotating sides based on wear. Judging from my cup 2s, this car is obliterating the fronts, which isn't surprising given its weight.

On the NT01 wheel/tire set I'll have to debate between the A052, or a weird combination of RE71Rs. Sadly the RE71R doesn't really have a good option for the 18x11 rear, I'm not sure if the 285/30r18 would be too much of a stretch, maybe the taller 275/35r18 would be a better choice. 18x10.5 squared would be ideal for the RE71R, and might be an option in the future. I'm not opposed to having 3 sets of track wheels, it's a minor inconvenience when loading the trailer and really opens up some options based on session goals.
Just went through a set of Yokohama A052 on Apex 18 inch wheels with 265 front10 and 295 rear11. I was pretty happy with them and on a short track, they were only 1.3 seconds off of Pirelli DH takeoffs.

Nankang AR1 in the mail 295/315 they run small - due on Monday, in time for my next visit to Laguna Seca.
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      07-09-2020, 09:18 PM   #83
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Quote:
Originally Posted by fanatic1 View Post
Quote:
Originally Posted by Gomeler View Post
The NT01 is 26.42" tall, and the rear Cup 2 is 26.8" tall. I wager the NT01 is nearly an inch wider, likely yielding a larger static contact patch than the Cup 2. It's possible the NT01's larger sidewall is causing the contact patch to narrow a bit at speed, but I'm having these contact issues on corners between 45mph and 85mph. The unknown variable is the age/heat cycle of these NT01s. The behavior reminds me of heat cycle cooked(25+) R7s, just incredibly unpredictable.

I won't be tracking the OEM wheels anymore after the Cup 2s cord. I've got a real nasty ~1.5" long gouge from a rock in the barrel of one of the rears, and I don't want to beat them up anymore. I'll likely just put another set of Cup 2s on them, and use that for any street driving I do until they age out.

My wheel/tire plan for the year is as follows:

Grab another set of EC-7, and try mounting the NASA spec Toyo RR, 295/30r18, onto an 18x11 and seeing if that clearances the front fender liner. If so, run 18x11 square and rotate based on wear, optimizing use of the set. If not then find some front tire option, possibly still the 295/30r18 on an 18x10, and continue rotating sides based on wear. Judging from my cup 2s, this car is obliterating the fronts, which isn't surprising given its weight.

On the NT01 wheel/tire set I'll have to debate between the A052, or a weird combination of RE71Rs. Sadly the RE71R doesn't really have a good option for the 18x11 rear, I'm not sure if the 285/30r18 would be too much of a stretch, maybe the taller 275/35r18 would be a better choice. 18x10.5 squared would be ideal for the RE71R, and might be an option in the future. I'm not opposed to having 3 sets of track wheels, it's a minor inconvenience when loading the trailer and really opens up some options based on session goals.
Just went through a set of Yokohama A052 on Apex 18 inch wheels with 265 front10” and 295 rear11”. I was pretty happy with them and on a short track, they were only 1.3 seconds off of Pirelli DH takeoffs.

Nankang AR1 in the mail 295/315 they run small - due on Monday, in time for my next visit to Laguna Seca.
I run the same A052 set up (265/295 on an 18) and they're fantastic. So much better than the star spec cup 2's. I'm moving to a 295/315 A052 as soon as the new barrels come in for the front wheels. I think that's going to be an ideal street/track set up.

The AR-1 is definitely in my radar though. May have to snag another set of wheels so try them out.
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      07-09-2020, 10:38 PM   #84
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Quote:
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Quote:
Originally Posted by fanatic1 View Post
Quote:
Originally Posted by Gomeler View Post
The NT01 is 26.42" tall, and the rear Cup 2 is 26.8" tall. I wager the NT01 is nearly an inch wider, likely yielding a larger static contact patch than the Cup 2. It's possible the NT01's larger sidewall is causing the contact patch to narrow a bit at speed, but I'm having these contact issues on corners between 45mph and 85mph. The unknown variable is the age/heat cycle of these NT01s. The behavior reminds me of heat cycle cooked(25+) R7s, just incredibly unpredictable.

I won't be tracking the OEM wheels anymore after the Cup 2s cord. I've got a real nasty ~1.5" long gouge from a rock in the barrel of one of the rears, and I don't want to beat them up anymore. I'll likely just put another set of Cup 2s on them, and use that for any street driving I do until they age out.

My wheel/tire plan for the year is as follows:

Grab another set of EC-7, and try mounting the NASA spec Toyo RR, 295/30r18, onto an 18x11 and seeing if that clearances the front fender liner. If so, run 18x11 square and rotate based on wear, optimizing use of the set. If not then find some front tire option, possibly still the 295/30r18 on an 18x10, and continue rotating sides based on wear. Judging from my cup 2s, this car is obliterating the fronts, which isn't surprising given its weight.

On the NT01 wheel/tire set I'll have to debate between the A052, or a weird combination of RE71Rs. Sadly the RE71R doesn't really have a good option for the 18x11 rear, I'm not sure if the 285/30r18 would be too much of a stretch, maybe the taller 275/35r18 would be a better choice. 18x10.5 squared would be ideal for the RE71R, and might be an option in the future. I'm not opposed to having 3 sets of track wheels, it's a minor inconvenience when loading the trailer and really opens up some options based on session goals.
Just went through a set of Yokohama A052 on Apex 18 inch wheels with 265 front10" and 295 rear11". I was pretty happy with them and on a short track, they were only 1.3 seconds off of Pirelli DH takeoffs.

Nankang AR1 in the mail 295/315 they run small - due on Monday, in time for my next visit to Laguna Seca.
I run the same A052 set up (265/295 on an 18) and they're fantastic. So much better than the star spec cup 2's. I'm moving to a 295/315 A052 as soon as the new barrels come in for the front wheels. I think that's going to be an ideal street/track set up.

The AR-1 is definitely in my radar though. May have to snag another set of wheels so try them out.
Next time our paths cross at the track, you are welcome to try them
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      07-09-2020, 10:43 PM   #85
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The NT01 is 26.42" tall, and the rear Cup 2 is 26.8" tall. I wager the NT01 is nearly an inch wider, likely yielding a larger static contact patch than the Cup 2. It's possible the NT01's larger sidewall is causing the contact patch to narrow a bit at speed, but I'm having these contact issues on corners between 45mph and 85mph. The unknown variable is the age/heat cycle of these NT01s. The behavior reminds me of heat cycle cooked(25+) R7s, just incredibly unpredictable.

I won't be tracking the OEM wheels anymore after the Cup 2s cord. I've got a real nasty ~1.5" long gouge from a rock in the barrel of one of the rears, and I don't want to beat them up anymore. I'll likely just put another set of Cup 2s on them, and use that for any street driving I do until they age out.

My wheel/tire plan for the year is as follows:

Grab another set of EC-7, and try mounting the NASA spec Toyo RR, 295/30r18, onto an 18x11 and seeing if that clearances the front fender liner. If so, run 18x11 square and rotate based on wear, optimizing use of the set. If not then find some front tire option, possibly still the 295/30r18 on an 18x10, and continue rotating sides based on wear. Judging from my cup 2s, this car is obliterating the fronts, which isn't surprising given its weight.

On the NT01 wheel/tire set I'll have to debate between the A052, or a weird combination of RE71Rs. Sadly the RE71R doesn't really have a good option for the 18x11 rear, I'm not sure if the 285/30r18 would be too much of a stretch, maybe the taller 275/35r18 would be a better choice. 18x10.5 squared would be ideal for the RE71R, and might be an option in the future. I'm not opposed to having 3 sets of track wheels, it's a minor inconvenience when loading the trailer and really opens up some options based on session goals.
Just went through a set of Yokohama A052 on Apex 18 inch wheels with 265 front10" and 295 rear11". I was pretty happy with them and on a short track, they were only 1.3 seconds off of Pirelli DH takeoffs.

Nankang AR1 in the mail 295/315 they run small - due on Monday, in time for my next visit to Laguna Seca.
I run the same A052 set up (265/295 on an 18) and they're fantastic. So much better than the star spec cup 2's. I'm moving to a 295/315 A052 as soon as the new barrels come in for the front wheels. I think that's going to be an ideal street/track set up.

The AR-1 is definitely in my radar though. May have to snag another set of wheels so try them out.
Next time our paths cross at the track, you are welcome to try them
Honestly, three sets of track wheels plus OEM? I really should see someone about this
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      07-10-2020, 03:01 AM   #86
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If I can ever travel again, I'll be hauling this car to a few bucketlist tracks. I'd like a set of 200tw for rain, and two sets of dry-weather tires. Not having a 15-30 hour tow ruined because I punctured a tire, corded a corner prematurely, or it rained a little bit.
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      07-10-2020, 10:52 AM   #87
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You're correct in my issue, post-apex grip on the NT01 has been garbage for me. Pre-apex the grip is on-par or better than the Cup 2.

Well now I'm embarrassed. I know when I unpacked them I examined the fronts, and they were mid-2018s. I clearly didn't examine the rears outside of depth gauging them. Mid-2017 on the rears

Thanks for asking that question. Think I'll order a set of NT01s ASAP to give them a proper test. Under $1k for a set, and if they wear like the fronts have been wearing, they'll be great warm-up tires before swapping to something stickier.
All good, those should still be ok if not subjected to poor storage conditions. NT01's grip all the way to the cords, in my experience. When just the two circumferential grooves remain you know you're in the good stuff. Tread isn't showing any weird deg?

If the 18" approach will equal or surpass OE in terms of forward traction, 305 NT01 on an 18 x 11 really should do it.

More context for what I'm suggesting as it applied to 992 911 development --

2) Enlarge the diameter of the rear wheels.

Calculations and simulations showed that enlarging the diameter of the rear wheels would improve dynamics even though it would also add weight. The 2020 Porsche 911 S and 4S now ride on 21-inch wheels at the rear and 20s up front, though the tire sizes haven't changed at 305/30 rear and 245/35 up front. While this influenced all of the surrounding areas of the suspension and the packaging of the car, Porsche felt it was worth the effort because it would make the handling more neutral and controllable. The company had experience with the practice as the 918 Spider and GT2 and GT3 cars already use staggered wheel sizes, and there are no better handling Porsches than those. Handling becomes more neutral because the bigger rear wheels provide greater rear end stability and grip without having to go with a wider tire.


Obviously, to each his own and I'm not trying to convince to run the OE wheels. I just think it's interesting that you've dropped 2" diameter, fitted a stickier, wider tire, and the back end is nowhere near as planted. I can't say that I sensed less grip with a 19" 305, but the 19" 275/305 setup was definitely not as communicative or alive. The driving dynamics weren't as optimal. That's why I bounced back.
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      07-10-2020, 11:06 AM   #88
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Tread wear and rubber appearance looks uniform front/rear, was measuring 4/32" across the tread before 7/2/2020, with some 3/32" measurements on the outside of one of the tires. I'll be going over the car this weekend, will re-measure the tires to see what's what.

I'd heard about the NT01 gripping to the cords, which is why I wasn't worried about the tires.
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