M4 GT4 wheels - 18x11 ET30, 20.3lb?

[Astro_train]

Originally Posted by XCUSE_M3

Suspension will be the factor on running the 10.5in all around. I do have a set of the titans and they are great and fit with no spacers and for sure the best bang for your buck. Normally run the GT4 wheels when running a 315 in the back. Those BBS wheels look to be out of my budget I will try and get some pics.

thanks for all the pics..

The BBS run around $3700 for a set... so its a middle ground between the Titan 7 and other more expensive brands.. The GT4 wheels run for around $2800 so not cheap either (well at least for me they are not..)

I definitely agree the Titan 7 being the best bang for the buck and cannot see any other brand out there offering a forge wheel for that price.

Not tracking my car.. just looking for a nice 18" aggressive set up. The GT4 wheels are just a tad too aggressive for me and I am not a fan of black wheels but I realize these are a track set up.

Lowering the car on KW HAS..
If I get the BBS and have to special order I plan to go with a squared set up with varying offsets.

18x10.5 +25 F 275/40/18
18x10.5 +37 R 295/35/18

The easier staggered version is (but I am trying to confirm if the faces of the 9.5 version have less concavity... I know the 10.5 models have the most concave, these wheels look best at maximum concave).

18x9.5 +23
18x10.5 +37

The smarter choice from a money standpoint is definitely to pick up a set of Titan TS5s. I think these wheels look better on a sedan though than a coupe. That is my other hesitation to getting these.

But I only plan on buying one set of wheels for this car and rather spend a little more since the GT4 look is what I think looks better on the car.

thanks again for posting the pics. Really helps make the decision a bit easier.

.

[MikeM5]

So awesome to see this wheel getting fitted to the E9X platform! Tempted to snag a set myself

Just to keep this thread GT4 focused, Astro_train PM sent about a possible wheel set that may work for you!

[Richbot]

It also looks like these are going to be the Supra GT4's wheel (with toyota centercaps, natch)

[slicer]

The RIA versus the GT4 wheel is an interesting comparison. I happen to have both on hand right now. The GT4 wheel is surprisingly light, great bang for buck. BBS RIA build quality is better. It simply has more details to the design, it's forged, and about 1/2 lb lighter. EDIT - I believe that both wheels are forged based on my research on the manufacturer of the GT4 wheels

Fitting 10.5 on the front is not all that difficult. Fitting an 11 on the front is possible but does require a specific setup. I don't think -4 camber is required based on my testing. I'm at -3.3 and believe I can fit an 11" wheel in front with my camber and 295's.

Pic of the two wheels side by side for comparison >>>>

RIA vs GT4 by slicerM, on Flickr

[fsmtnbiker]

I run 18x11's and 295/30-18 square on my car as the 'street' setup. Apex EC7 18x11 ET25, with a 5mm front spacer (3mm is not enough, 5mm leaves ~2mm clearance to the strut body.) -3 camber, KW Clubsports with 5.5" springs. Rubs on the fender liner when turning but no other rubs/issues.

[Astro_train]

Originally Posted by slicer

The RIA versus the GT4 wheel is an interesting comparison. I happen to have both on hand right now. The GT4 wheel is surprisingly light, great bang for buck. BBS RIA build quality is better. It simply has more details to the design, it's forged, and about 1/2 lb lighter.

Fitting 10.5 on the front is not all that difficult. Fitting an 11 on the front is possible but does require a specific setup. I don't think -4 camber is required based on my testing. I'm at -3.3 and believe I can fit an 11" wheel in front with my camber and 295's.

Pic of the two wheels side by side for comparison >>>>

RIA vs GT4 by slicerM, on Flickr

really appreciate you chiming in, I been googling both wheels comparing both(your posts come up BTW ), I did not know the GT4 wheel was not forged. So for around $1k more, the RI-A is the clear choice to go with.

So what size of spacer would be needed to clear the stock calipers on an M3/M4 with on the GT4 wheel? No one seems to be able to post an exact size.. everyone just says 25 mm. If it is 25 mm one would be at +5 effective offset and with a 11 inch rim, that is pretty aggressive... if this is the case, to gain half an inch of wheel size isn't worth it so again, the BBS wheel would be the clear choice.

and the RIA Is being discontinued.. so I was told.. is this accurate? Appreciate all the info Slicer.

I am looking to have two sets of aftermarket wheels for this car for the next 3 years not including the stock wheels. I picked up a set of Titan 7s and the RI-As are at the top of my list as second choice.. I think they are a good middle ground for style, quality and price.

[Richbot]

275/35-18’s and 285/30-18’s both can be stuck on an 11. It’ll be stretchy but it’s in the standard rim width range for those sizes for most tire models, and ought to be pretty doable for most people fit wise

Poke dat rim son

[dparm]

Brake clearance looks better on the BBS wheels, but that's just me eyeballing it.

Curious who is making these for BMW. Could it be someone like BBS, or is it one of the other OEM suppliers like Ronal, Wolf, Speedline, etc?

[OG Shark]

Is there any benefit to running an 11” wheel if you are still running 305 or less? Especially in the front where fit is a bit more difficult?

My understanding is for a 295 (or 305 pirelli which runs closer to other 295s) that a 10.5 is a better wheel choice? If you want to run the 315 in the back might not a staggered 10.5 front & 11” rear be a better choice?

[dparm]

Originally Posted by OG Shark

Is there any benefit to running an 11” wheel if you are still running 305 or less? Especially in the front where fit is a bit more difficult?

My understanding is for a 295 (or 305 pirelli which runs closer to other 295s) that a 10.5 is a better wheel choice? If you want to run the 315 in the back might not a staggered 10.5 front & 11” rear be a better choice?

I would look at the spec sheet for the tire you're running and see what they recommend. Every tire is a little bit different and the scrubs/R-comps seem to have a sweet spot.

FWIW I run an 11" wheel with my 315/30R18s up front.

[Richbot]

There's benefit. You'd have to test to know what it is. On the steer axle you want as much rim support as possible for whatever tire you have on it - but the tradeoffs you might make to get that support might not be worth it, which is why we have stopwatches

I wouldn't give up the possibility of rotating tires for a little more rear tire on a car that struggles to put down 250ft/lb of torque on a dyno, but that's me

[PrimeBMW]

Yes. Look at the specific tire spec. For example a 280 Yokohama slick likes an 11" wide rim where a 300 likes a 12". Michelin slicks are similar. Obviously most tires don't require wheels that wide.

[slicer]

One step closer to testing the GT4 wheels on my e92.

295/30/18 Nankang AR1's installed

M4GT4 by slicerM, on Flickr

M4GT4 by slicerM, on Flickr

[slicer]

Sorry I just saw this post. My answers below.

Originally Posted by Astro_train

really appreciate you chiming in, I been googling both wheels comparing both(your posts come up BTW ), I did not know the GT4 wheel was not forged. So for around $1k more, the RI-A is the clear choice to go with.

So what size of spacer would be needed to clear the stock calipers on an M3/M4 with on the GT4 wheel? No one seems to be able to post an exact size.. everyone just says 25 mm. If it is 25 mm one would be at +5 effective offset and with a 11 inch rim, that is pretty aggressive... if this is the case, to gain half an inch of wheel size isn't worth it so again, the BBS wheel would be the clear choice.

You are welcome - happy to help when I can. It's not the caliper that's the issue. It's the suspension. Based on my research I believe only a 12mm spacer is needed with a 295. However I will know more after I do some testing. I will test on my e92. The e92 and the f8x have very similar front fitment / space.

Originally Posted by Astro_train

and the RIA Is being discontinued.. so I was told.. is this accurate? Appreciate all the info Slicer.

You are welcome. The RIA is not being discontinued as far as I know.

Originally Posted by Astro_train

I am looking to have two sets of aftermarket wheels for this car for the next 3 years not including the stock wheels. I picked up a set of Titan 7s and the RI-As are at the top of my list as second choice.. I think they are a good middle ground for style, quality and price.

RIA is an amazing bang for buck IMO.

[slicer]

Originally Posted by OG Shark

Is there any benefit to running an 11” wheel if you are still running 305 or less? Especially in the front where fit is a bit more difficult?

My understanding is for a 295 (or 305 pirelli which runs closer to other 295s) that a 10.5 is a better wheel choice? If you want to run the 315 in the back might not a staggered 10.5 front & 11” rear be a better choice?

295 on an 11 is ideal IMO. It's at the max wheel width spec for that tire size. As a result you get the most out of the tire. More wheel width increases tread width and sidewall support. That being said, I don't recommend stretching beyond the manufacturer's recommended width. However there are instances where car manufacturers use wheels wider than the tire's recommended spec. For example the 997 GT3 uses a wheel wider than the tire's spec.

[slicer]

Originally Posted by dparm

Brake clearance looks better on the BBS wheels, but that's just me eyeballing it.

Curious who is making these for BMW. Could it be someone like BBS, or is it one of the other OEM suppliers like Ronal, Wolf, Speedline, etc?

SAI - SuperAlloy Engineering makes these wheels for BMW. Upon researching the company I believe they only make forged wheels (therefore these are forged). SAI makes forged wheels and forged suspension parts for OEM's like BMW, Audi, Porsche, Mercedes, and Ferrari. It is a Tiawanese company.

http://superalloyengineering.com/company/profile/

[dparm]

Originally Posted by slicer

SAI - SuperAlloy Engineering makes these wheels for BMW. Upon researching the company I believe they only make forged wheels (therefore these are forged). SAI makes forged wheels and forged suspension parts for OEM's like BMW, Audi, Porsche, Mercedes, and Ferrari. It is a Tiawanese company.

http://superalloyengineering.com/company/profile/

Good info, thanks. Makes me wonder if these are the guys doing contract work & private labeling for all of the forged wheels these small "bespoke" wheel companies suddenly have.

[roastbeef]

Originally Posted by slicer

One step closer to testing the GT4 wheels on my e92.

295/30/18 Nankang AR1's installed

M4GT4 by slicerM, on Flickr

M4GT4 by slicerM, on Flickr

i'm really interested in this option for my next set of track wheels. please report back how these fit on your e92.

i'm running arc-8 18x10.5 et27's right now. while they have been great, they are gloss black and getting another gloss black set has been challenging. so i'm thinking the next time i'm in the market for track wheels, this might be a nice option.
i'm also interested how the 295's fit up front since i'll likely have a similar setup once i get there.

[dparm]

The AR-1s are supposed to be a great track tire. There's been a ton of chatter and test info on one of the HPDE groups I'm in.

[Kelse92]

Originally Posted by dparm

The AR-1s are supposed to be a great track tire. There's been a ton of chatter and test info on one of the HPDE groups I'm in.

Post up a link??
I’ve been curious about them. The cost savings isn’t a ton, but it’s always interesting to see and hear about new stuff...

[Richbot]

http://speed.academy/100-tread-wear-...c1-toyo-r888r/

[dparm]

Originally Posted by Kelse92

Post up a link??
I’ve been curious about them. The cost savings isn’t a ton, but it’s always interesting to see and hear about new stuff...

Are you a member of this group?
https://www.facebook.com/groups/680392535693234/


Louis Gigliotti bought a container full of them and has been posting a lot of great feedback and data on laptimes from his race cars.