Slicks

[SYT_Shadow]

Originally Posted by The_Werm

Do u run a square setup?

I really like the look of the 513m from the m2cs racing. 10.5 x 18 et 46. Is it worth it to make these work? Is running a large spacer an issue?

Would run a 27/65/18 slick.

I only run square setups on dedicated wheels. If I had a street car that goes to the track every blue moon then I'd run staggered on the OEM wheels.
The fronts wheels get more beat up than the rears in these cars anyway. I like being able to rotate.

Running a large spacer is not, in my opinion, a problem. BMW Motorsports runs a 41mm spacer on the M2 CS and around 25mm on the M4 GT4.

ET46 10.5 fits the rear happily with a 10mm spacer. Up front, you would need a 25mm spacer. It's doable. I find it's easier to run the TA5R wheel in 10.5 ET36: no spacer in the rear, 12 or 15mm spacer up front.

[NYG]

Originally Posted by ///Mobbin

Do ya'll still balance the wheels when you run slicks?

Only if you get zero slip. Even with beaded forgelines, I get significant slip with something like an A7. Once that slips - the vibrations become unbearable.

[The_Werm]

Originally Posted by SYT_Shadow

I only run square setups on dedicated wheels. If I had a street car that goes to the track every blue moon then I'd run staggered on the OEM wheels.
The fronts wheels get more beat up than the rears in these cars anyway. I like being able to rotate.

Running a large spacer is not, in my opinion, a problem. BMW Motorsports runs a 41mm spacer on the M2 CS and around 25mm on the M4 GT4.

ET46 10.5 fits the rear happily with a 10mm spacer. Up front, you would need a 25mm spacer. It's doable. I find it's easier to run the TA5R wheel in 10.5 ET36: no spacer in the rear, 12 or 15mm spacer up front.

Yeah I've been wearing out the rs4s too quickly on my 513m and want more grip lol/ the ability to rotate as the fronts get destroyed.

[e36clubracer]

Where you guys buying your slicks from? Either new or scrubs?

[Monkey Throttle]

Would you mind ball parking:

What type of slick are you running?
How many heat cycles are you getting?
How would you rate the slick 1-10 based on performance?
How would you rate the slick 1-10 based on price/performance/lifespan?

[bimmerboyE92]

Originally Posted by Monkey Throttle

Would you mind ball parking:

What type of slick are you running?
How many heat cycles are you getting?
How would you rate the slick 1-10 based on performance?
How would you rate the slick 1-10 based on price/performance/lifespan?

For $600 (Pirelli DH scrubs) a set it's worth trying them. 3-4 full track days of absolute pounding.

10 for performance and 10 for price! However, it will take 3 hard laps to get enough heat into them... be honest with yourself if you are ready for slicks. It's not an arrive and drive type of tire... you have to take care of pressure (below 31lbs hot), you have to take time to heat them (or you will be disappointed), need brakes to match (or you will overheat them), and lots of negative camber.

[sly1types]

Hey Guys, i am looking at going with 305/660 pirelli scrubs on 10.5F and 11R.

My question is what are you guys seeing for the G load in long corners? Does the M4GT4 racecar have the exact same oil sump as our cars? My local track has long carousel, i monitor oil psi and its always at 70psi there and never drops below 50psi running 265/305 RE71Rs.

Also did you raise your spring rates much? I'm on 700F and 600R with 175psi can pressure on MCS 2way remotes.

Thanks!

[bimmerboyE92]

Originally Posted by sly1types

Hey Guys, i am looking at going with 305/660 pirelli scrubs on 10.5F and 11R.

My question is what are you guys seeing for the G load in long corners? Does the M4GT4 racecar have the exact same oil sump as our cars? My local track has long carousel, i monitor oil psi and its always at 70psi there and never drops below 50psi running 265/305 RE71Rs.

Also did you raise your spring rates much? I'm on 700F and 600R with 175psi can pressure on MCS 2way remotes.


Thanks!

660s may or may not rub in the front. Typically people go with 305/645 square. The shorter tire buys a little extra clearance. However, I do know the M4 GT4 runs a 305/660.

[sly1types]

Originally Posted by bimmerboyE92

660s may or may not rub in the front. Typically people go with 305/645 square. The shorter tire buys a little extra clearance. However, I do know the M4 GT4 runs a 305/660.

I know there are a few guys that run a 305/30/19 up front so thats like a 26.2 OD, I might have to heat up/manipulate the fender liner.

The reason I want to run a 660 is i have a friend that can get those for decent price with only 1 heat cycle. He said the 645 is harder to come by on a regular basis.

[F80Speed77]

Can confirm 305/30/19 RT660 fits on the front with a 19x10.5" at +10 offset on stock damper with GC Coilover Kit.

[sly1types]

Originally Posted by F80Speed77

Can confirm 305/30/19 RT660 fits on the front with a 19x10.5" at +10 offset on stock damper with GC Coilover Kit.

Awesome! Great to hear, I do have 6" x 2.25" springs with helpers which I may go to 5" that's why I was also see what springs rates guys are running as I could move my 700F 6" to the rear and then get 800F 5" so I would easily clear.

How do you like the rt660s? What can you compare them to? I was thinking about those for wet/damp days or cool mornings.

[F80Speed77]

I run 2.5" springs on the front so the 2.25 ones should give you a little more wiggle room! I run 450 front and 800 rear springs with an H&R FSB set to full stiff.

RT660's were great this past weekend at Gingerman in 80deg heat with sunshine. Very fast on the first heat cycle and very manageable once you start to lose transaction. They were a little vague i think compared to the RE71R of the same size but the tire is probably a little overstuffed on the wheel since it does run slightly wider than the RE71R as well. Grip is phenomenal.

We ran pressures a little lower than what Falken recommended and wear looks really good so far. Target hot pressures were 32F 30R. Pyro data showed the middle of the tire was crowning even with -3deg of rear camber at over 30psi. Camber is key to maintaining these tires longer term so make sure you get a decent amount into it for the track.

Here are the tires ive run on the F80 in ranked order lol

305/30/19 Falken RT660
305/30/19 Bridgestone RE71R
295/30/19 Goodyear Supercar3
275/35/19 Hankook RS4
285/35/19 Bridgestone RE71R (destroyed fenders!)

[TractionControlDelete]

Originally Posted by e36clubracer

Where you guys buying your slicks from? Either new or scrubs?

Also interested

This setup seems like it will work. Will try it as I have 18x10 ET 25 Apex:

https://www.bimmerpost.com/forums/sh...php?p=26794493

[sly1types]

Originally Posted by F80Speed77

I run 2.5" springs on the front so the 2.25 ones should give you a little more wiggle room! I run 450 front and 800 rear springs with an H&R FSB set to full stiff.

RT660's were great this past weekend at Gingerman in 80deg heat with sunshine. Very fast on the first heat cycle and very manageable once you start to lose transaction. They were a little vague i think compared to the RE71R of the same size but the tire is probably a little overstuffed on the wheel since it does run slightly wider than the RE71R as well. Grip is phenomenal.

We ran pressures a little lower than what Falken recommended and wear looks really good so far. Target hot pressures were 32F 30R. Pyro data showed the middle of the tire was crowning even with -3deg of rear camber at over 30psi. Camber is key to maintaining these tires longer term so make sure you get a decent amount into it for the track.

Here are the tires ive run on the F80 in ranked order lol

305/30/19 Falken RT660
305/30/19 Bridgestone RE71R
295/30/19 Goodyear Supercar3
275/35/19 Hankook RS4
285/35/19 Bridgestone RE71R (destroyed fenders!)

This my 265/35/19 re71r with -3.2 after 20 sessions

How long is the optimal window on the rt660? I know the re71r lap 3 and 4 mid morning is where the PBs are. On Saturday I had my right rear up to 195F deg😳

[F80Speed77]

Yeah you could probably use a little more camber up front haha, RT660 is best in the first 3 laps, you'll have to manage it after that.

[NYG]

Fresh DH > Hoosier A7 > Hoosier A7 Scrubs > DH Scrubs

[bimmerboyE92]

Originally Posted by NYG

Fresh DH > Hoosier A7 > Hoosier A7 Scrubs > DH Scrubs

For me the DH scrubs were faster than A7 scrubs. But we’re talking scrubs!

[NYG]

Originally Posted by bimmerboyE92

For me the DH scrubs were faster than A7 scrubs. But we’re talking scrubs!

Theoretically they should be, especially qualifying scrubs. I have a hard time trusting the # of cycles, even when I get them from shops I have a good relationship with.

A7s fall off more drastically than DHs but they seem to hold that point almost all the way to cord.

The DH is clearly the superior race focused tire (although I hear that Michelin slicks are a lot better) but I've really become an A7 fanboy. There's no foreplay with those tires - they're just fast all the time.

[bimmerboyE92]

We can only get 2 fast laps out of A7s before they just start to get too hot. Same for you? The DHs take 4 laps or more to warm up for full speed runs.

[NYG]

Originally Posted by bimmerboyE92

We can only get 2 fast laps out of A7s before they just start to get too hot. Same for you? The DHs take 4 laps or more to warm up for full speed runs.

That happened to me (around 4 laps at Sebring) when I was running them at the typical lower pressures that I run other tires with but the sidewall flex of A7s is huge. When I ran them a little higher, I was able to get around 6 laps and the fall off showed noticeable oversteer in corner entry but controllable - they'd give up a little but never completely.

[bimmerboyE92]

Originally Posted by NYG

That happened to me (around 4 laps at Sebring) when I was running them at the typical lower pressures that I run other tires with but the sidewall flex of A7s is huge. When I ran them a little higher, I was able to get around 6 laps and the fall off showed noticeable oversteer in corner entry but controllable - they'd give up a little but never completely.

Hmmm, we shoot for 38 hot on Hoosier (A7 or R7) and once they get over 200deg, the compound just wants to give up and tear away.

[NYG]

Originally Posted by bimmerboyE92

Hmmm, we shoot for 38 hot on Hoosier (A7 or R7) and once they get over 200deg, the compound just wants to give up and tear away.

On the Z06 34PSI @ ~130F was grip city. Carried wild speeds into some corners (accidentally too - scared the shit out of me at first then I realized how crazy A7s are.