Sponsored by The Tire Rack

[drwankel]

Excited to post this as it has been a long time coming. A couple of years ago- I added a Harrop supercharger to my e92 ZCP M3. I quickly found that the stock 265 rear tire was incapable of putting additional power to the ground. I could spin the tires in 1st, 2nd and 3rd. Redline runs in 1st and 2nd were not possible in any capacity.

Realizing I needed to go to some wider tires, I started investigating my options. The reality was not good. The obvious answer was the GTS tire sizes, but the tire selection for an 285/30/19 is abysmal. Pilot Super Sports were available, but the PS4S tire was unavailable in that size. Availability of even the PSS was not good. I will say now that as of 2022, it does look like Michelin is finally making 285/30/19s in PS4s.

My end tire size goal was a 275/30/19 Front 295/30/19 Rear. While you can technically run these on the stock m359s, the sizing is beyond what most tire manufactures would reccomend. You simply wont have appropriate sidewall support with those sizes on a 9" front and a 10" rear.

The answer was obvious- I needed wider wheels. A 10" front and 11" rear would do the job, and based on my research a +25 offset for both front and rear wont rub on stock ZCP suspension. The problem was I absolutely loved the m359 wheels, and nothing seemed like a good replacement.

I started a thread here asking if anybody made some replicas in a wider size, and there were wheels that were similar, but nothing that was an exact match.

After a couple of months I called Avant Garde and asked if they would be able to do a custom run of m359s that were forged in the widths and offsets I specified. They responded that actually, yes, they could but it would be around $6000 for the set. I thought about it for a while.

Eventually, either someone had read my thread, or had the exact same idea as me at the same time. I wont drop names here, other than the fact the fact this person organizes group buys, and isn't allowed on the forum due to reasons I wont get into here as I dont want to have this thread locked.

This person organized a group buy with Avant Garde for 19x10 + 25 and 19x11 + 25 M359s, but instead of forged, they were flow formed. The price was decent, and knowing that this is likely a once in a lifetime thing, I jumped on it.

Many months passed, and in the fall I finally received the wheels. I started collecting the odds and ends I needed to do the install. The plan was to install tires and the wheels once winter was winding down. TPMS sensors last about 10 years due to the battery, and as the car is now 10 years old, it was a logical time to replace them.

Fast forward to today- and I've finally installed them. 19x10 +25 front with a 275/30/19 Michelin PS4S tire, and 19x11 +25 rear with a 295/30R19 rear tire. NO SPACERS.

The results were everything I was hoping they would be. Absolutely no rubbing on stock ZCP suspension. I can also finally lay down the power from the Harrop Supercharger in all gears. This IMHO may be the best possible wheel setup for the e9x M3. The only improvement would be a forged set, and I may pursue that one day.

And now for some pictures of the result:

[Longboarder]

These look great.

Just a note on straight line traction: Wider doesnt mean much of anything.

Wide tires help with weight and lateral accel which is why for the race track, wider is better.

For straight line acceleration, tire compound and contact patch are everything. Tire compound needs to be as soft as possible, and the contact patch is a complex formula but what you really want is volume - think about dragster tires. They are the opposite of low profile. Going down to a 30 aspect ratio will hurt you. 275 35 may be a taller and more effective sidewall. The most important thing is to "wrinkle" the sidewall as that optimizes the contact patch. U can increase the contact patch dramatically even on low profile tires by running lower tire pressure.

I run very low rear tires pressure on my cars, especially in winter when roads are colder, to aid in off-the-line traction. My 991 Turbo S will go 0-60mph in 3.0 seconds at 40psi and drops a full second to 2.0 seconds at 20psi. For my M3 the launch is optimized around 26psi on PS4S.

You may be getting better traction off the line just because your rear wheel and tire gained a few pounds over whatever was on there before as that extra unsprung weight takes more power to move. Will also hurt rolling accel.

[drwankel]

I would argue that a 295/30/19 has more volume and a larger contact patch than a 265/35/19. A 305/30/19 is nearly identical in sidewall height as a 265/35/19 to illustrate how close a 295/30/19 is. That extra width does add to to contact patch. That being said- there are weight considerations. I've actually saved weight weight vs the stock wheels, but there is the unavoidable weight gain from the larger tires. This is is additional unsprung mass, and it is noticeable to me- but I know what I am looking for. I will say that it is less noticeable than I was expecting.

Anyway- I noticed that it appears there is a spot of rub on the front. Investigating options. Rears look great. The fronts are 19x10 +25. This is the same size and offset as the factory rear wheels. People use them in square setups, and a 275/30/19 was said not to rub this way. If anyone reading has run a square m359 setup, I'd love to hear from you.

[Throatpunch]

The one gripe I have is that everyone compares just tire sizes to determine if they will rub/not rub. Every tire is different. Take for example this photo if a 255 series nt-05 on the right and a 255 series federal 595rs-rr on the left



In terms of rub it doesn't seem that bad

[Davisca455]

Same experience on my car when the blower was installed.
The OEM 265 rears stood no chance.

Was able to squeeze some 305/30/19s on 19 x 11, ET43 on the back of the car, but needed some 5mm spacers to keep the inboard sidewall from touching the fender liner.

The improvement in straight line drivability on a hard takeoff, was immediately noticeable and much appreciated.

[Longboarder]

Originally Posted by Davisca455

Same experience on my car when the blower was installed.
The OEM 265 rears stood no chance.

Was able to squeeze some 305/30/19s on 19 x 11, ET43 on the back of the car, but needed some 5mm spacers to keep the inboard sidewall from touching the fender liner.

The improvement in straight line drivability on a hard takeoff, was immediately noticeable and much appreciated.

I agree the 265 PZero's were a joke.

I experimented with many tires / wheels / sizes on my older supercharged e92.

Best traction off the line on the streets/unprepped by a landslide is Toyo R888 and successor R888r. Second best is PS4S and predecessor PSS. RE71R surprisingly not bad for a tire that needs some heat to work. Width didnt matter. LOW tire pressure (mid 20's was the key).

Don't be afraid to run with the TPMS light on all the time.

I was able to get very consistent 3,5 0-60mph in the supercharged M3 even having to short shift second gear because 1st will spin over 6500. This is with no launch just punching throttle. At airstrips I outlaunched stuff like Audi R8v10 AWD and other AWD cars. On my YouTube channel.

[Davisca455]

Originally Posted by Longboarder

I agree the 265 PZero's were a joke.

I experimented with many tires / wheels / sizes on my older supercharged e92.

Best traction off the line on the streets/unprepped by a landslide is Toyo R888 and successor R888r. Second best is PS4S and predecessor PSS. RE71R surprisingly not bad for a tire that needs some heat to work. Width didnt matter. LOW tire pressure (mid 20's was the key).

Don't be afraid to run with the TPMS light on all the time.

I was able to get very consistent 3,5 0-60mph in the supercharged M3 even having to short shift second gear because 1st will spin over 6500. This is with no launch just punching throttle. At airstrips I outlaunched stuff like Audi R8v10 AWD and other AWD cars. On my YouTube channel.

Thanks for sharing your experience.

My use is track days, trying to get the car to grip on corner exit.

I happen find it very interesting that you employed short shifting as a tactic.
I don't use DSC, but have gravitated to using the upshift paddle to get the car to stop spinning.

I'm just not skilled enough to manage the throttle consistently when leaving a turn in 2nd gear, so I just started leaving in 3rd instead.
It just makes for a less stressful day at the track for me.

The clip below is an example of using the upshift paddle to help the rear tires (305 PS4s) re-grip.
It's out in the country side, not on track, but it's fairly representative of what would happen exiting slow turns in 2nd gear.

(I just got some NT01s, so I'll likely try some more aggressive exits, T2 and T11, next month at Laguna Seca)

[Longboarder]

Originally Posted by Davisca455

Thanks for sharing your experience.

My use is track days, trying to get the car to grip on corner exit.

I happen find it very interesting that you employed short shifting as a tactic.
I don't use DSC, but have gravitated to using the upshift paddle to get the car to stop spinning.

I'm just not skilled enough to manage the throttle consistently when leaving a turn in 2nd gear, so I just started leaving in 3rd instead.
It just makes for a less stressful day at the track for me.

The clip below is an example of using the upshift paddle to help the rear tires (305 PS4s) re-grip.
It's out in the country side, not on track, but it's fairly representative of what would happen exiting slow turns in 2nd gear.

(I just got some NT01s, so I'll likely try some more aggressive exits next month at Laguna Seca)

Nice vid! Reminds me of the days of getting squirrelly in 2nd. Not possible at stock power with grippy tires.

Yeah tires for the track are altogether different than tires that work on the street with little to no heat in them. Cup2 is a nice compromise tire for both. Same with NT01's. If not entirely dry and freezing temps i remember PS4S or NT05's weren't bad since they dont need much heat to work.

But nothing beats a dedicated track tire. I'd run whatever dogbone uses that guy has the fastest e9X on the planet and it's supercharged.

[drwankel]

To update this thread, it appears that a 275/30/19 PS4S tire was too wide for this setup. Switched to a 265/30/19 PS4S and that appears to have solved the rubbing issue. Will update this thread if I notice anything else out of whack. I strongly suspect that the wide shoulders of the PS4S tires are to blame here. A 275/30 from a different brand may work without issue.

The learning here is if someone says their setup doesn't rub- make sure you are taking into account what tire brand and model they were running when planning your setup. In hindsight, out of all the 275/30/19 19x10 +25 success in the front stories, I don't quite recall one that was PS4S specifically.

Expensive lesson.

[MpowerMike]

Beautiful setup! Where can we place an order for these m359’s in these specs ?

[drwankel]

As far as ordering- I can't name the person/group by name due to some forum political shenanigans, but this person does group buys and frequents the facebook e9x m3 group. Sorry I can't be more specific than that.

A few updates on things. Dealing with some intermittent steering wheel vibration around 70-80mph on the freeway since installing the wheels. Had the tires re-balanced by someone using a road force balancer the right way. Got it down to 5lbs left and 7lbs right. Vibration is improved, but not 100% resolved.

The vibration was there on my old wheels and tires, (ps4s 245s on OEM M359 wheels), but much less pronounced. Figured it was balance then, since it had been quite a while since I had the tires rebalanced. Never got them rebalanced because I was about to move to the wide setup anyway.

Anyway- back to the current setup. Now that I know balance should be right, I'm looking at refreshing my thrust arm bushings, or going to a monoball setup. Car has a touch over 60k, and is 10 years old, so it may be time to replace those bushings. Hopefully that solves it.

Lastly, I will say the AG paint is every bit as cheap as people make it out to be. Already have paint chipping on the rear and haven't even done 300 miles yet. OEM ZCPs did over 60k and never had paint chipping. Not even sure what to do about this one yet.

[jra85]

Originally Posted by drwankel

As far as ordering- I can't name the person/group by name due to some forum political shenanigans, but this person does group buys and frequents the facebook e9x m3 group.

I think posting a link for where to purchase a product is acceptable. He got banned for repeatedly advertising his business and refusing to become a forum sponsor:
https://bit.ly/3hQkXf6

[shimmy23]

Originally Posted by drwankel

To update this thread, it appears that a 275/30/19 PS4S tire was too wide for this setup. Switched to a 265/30/19 PS4S and that appears to have solved the rubbing issue. Will update this thread if I notice anything else out of whack. I strongly suspect that the wide shoulders of the PS4S tires are to blame here. A 275/30 from a different brand may work without issue.

The learning here is if someone says their setup doesn't rub- make sure you are taking into account what tire brand and model they were running when planning your setup. In hindsight, out of all the 275/30/19 19x10 +25 success in the front stories, I don't quite recall one that was PS4S specifically.

Expensive lesson.

i hope i dont have this same issue with an 18" wheel. 275/35/18

edit: was looking at your pics (thank you for sharing pics!) and a 275/35/18 has a slightly smaller diameter so maybe i'll be ok.

[drwankel]

Well, what a debacle this has been.

Already have paint flaking off one of the rears.

I may have identified the vibration. One of the fronts appears to be bent, and shows a wobble while spinning by hand. These wheels are just cheap. May go back to stock wheels. The traction is great, and I love the look but if it isn't going to drive smooth on the highway, there's no point.

Video below of the wobbling caused by the multiple bends:

https://www.youtube.com/shorts/zZgyHwRUTb8

[spammysammich]

What a bummer. Sorry they didn't work out.

[Ajolives]

Originally Posted by drwankel

Well, what a debacle this has been.

Already have paint flaking off one of the rears.

I may have identified the vibration. One of the fronts appears to be bent, and shows a wobble while spinning by hand. These wheels are just cheap. May go back to stock wheels. The traction is great, and I love the look but if it isn't going to drive smooth on the highway, there's no point.

Video below of the wobbling caused by the multiple bends:

https://www.youtube.com/shorts/zZgyHwRUTb8

Sorry to hear about the wheels, they would be the ultimate setup especially with the Harrop.

Don't want to derail the thread but I've been chasing the same vibration for about two years now. Still scratching my head on it.

I've virtually eliminated it but every now and again it comes back, but only for a minute or two every other month or so. I agree that it's got to be worn suspension - I've replaced everything except tie rods so that's my next focus. I do run 15mm spacers with OEM M219 wheels and found that I was losing lug nut torque after a bit of driving (1-2k miles). Maybe with the new wheels and increased offset that could have something to do with it.

[DjMarkOne]

Originally Posted by spammysammich

What a bummer. Sorry they didn't work out.

I agree. I was also thinking about purchasing a set, but this makes me think otherwise

[drwankel]

I'm currently pushing AG to have the entire set replaced.

Again, we are talking about a 2 major bends in the front right, a minor one on the front left, and paint chipping on the left rear. The rears could have bends in them too for all I know but I just cant spin them by hand like the fronts as shown in the video in my last reply.

If they can give me a powdercoated set (gunmetal is fine) and verify the wheels are straight and true prior to shipment I can give it another go.

Currently they just want me to send the right front in, which means I need to have it dismounted, ship it, leave the car on jack stands for a few weeks, wait for the replacement to arrive, re-mount and rebalance all at my expense.

Not cool when its their screwup. They need to just do the right thing and advance RMA me a not flawed product on their dime. We'll what happens. If they don't then this thread will be here for all time for folks to see.

[nycplumber]

That's a crappy situation. When it comes to this car the only non forged wheel I would consider is from Apex. AG is definitely much lower in quality as expected from it's price. For what you paid you could have probably gotten forged wheels from titan 7 for a little more. Might be a route to consider next time

[turbostar93]

Originally Posted by drwankel

Well, what a debacle this has been.

Already have paint flaking off one of the rears.

I may have identified the vibration. One of the fronts appears to be bent, and shows a wobble while spinning by hand. These wheels are just cheap. May go back to stock wheels. The traction is great, and I love the look but if it isn't going to drive smooth on the highway, there's no point.

Video below of the wobbling caused by the multiple bends:

https://www.youtube.com/shorts/zZgyHwRUTb8

Hi. just want to let you know im experiencing the same issue with my ag 359, super poor painting quality ( mine are silver ). i only saw that after getting them, the coating is scratching already around the hub cap and close to the tyres. honnestly for the price, its a shame
but i dont have any vibrations issue atm

[ARS18]

This makes me feel a lot better about ordering a new set of OEM 359s. I was close to getting the AGs.

[kerrit]

+1 on Avante Garde poor paint quality, had chips within a week of normal driving.