Black & Tan 332iT

[Bry5on]

Front brakes went in and got bedded tonight. Rears will have to follow this weekend.

So far I’m pleased with the more immediate and confident pedal. The dead zone before pad bite is definitely reduced, and there’s less weird feedback on long downhill braking. Looking forward to doing the rears now.

The scales had these at exactly one pound less per front corner than the 325mm euro setup I had before. Not a bad tradeoff, although I swear I could feel the change in inertia from the bigger rotors. Probably just placebo..

[Bry5on]

Calipers arrived last night, so I swung in to the machine shop this morning for an hour to knock out the 5.5mm machining needed to make these fit the 345mm ZCP rotors. These calipers are nearly perfect, really pleased with the paint and seal condition! Looks like the pads in the rear calipers were still the ones from the factory! Fronts were replaced textars

[Bry5on]

It’s been a little bit.. now that it’s summer and warm I’m chasing overheating again. In pursuit of solving that, I swapped the M3 aux fan and radiator ducting in. An improvement, but no dice. The car still overheats on hot days uphill with AC on, even at highway speeds. Maybe another radiator is in the cards, as I’ve been through three thermostats, two thermostat housings, two water pumps and two radiators. Really strange, super repeatable and temps are actually going up, it’s not just the gauge. I’ll get it eventually.




I also made and added some 6mm spacers to the stock M3 springs to bring it more to ZHP height. The roads around me really are shit and this made a great difference.



And last, I swung over to mrgizmo04’s place to test fit my wheels over 996 brakes, as by the measurements it was going to be super close and I didn’t want to commit if it was going to require a large spacer. Well, it was super close, just over 1mm of clearance to the 345mm brakes and 996 calipers over the 17x9 et47 wheels. I ordered some 6mm spacers to make it 2.5mm and placed orders for black Porsche calipers and all the parts needed for the brake conversion. I miss that Porsche pedal feel and one ride sold me on the swap. That, and the fact that my wife’s SUV and my 50 year old stock-brake sedan have better pedal feel than my M3 setup..



Other than that, just putting the miles on. It’s doing great.

[Bry5on]

Math worked out once again. Perfect fitment of the 17x9 et52 e82 1 series wheels after adding some spacers. I’m not a fan of spacers, but there really wasn’t another option that fit the requirements. These end up being 7lb lighter per corner, dropping almost 30lb.

In front, with a 245/40/17 on a 17x9 et47 (after 5mm spacer) wheel, there’s 3.5mm clearance to the strut and just a few millimeters of tire past the fender with 2.15 degrees of camber from flipped strut hats set full positive. We’ve successfully preserved the correct factory scrub radius and steering feel.

Measurements are coming out at around 3mm clearance to 996 calipers, although I’m going to need to test fit this on another car before I commit to changing the brakes.

In the rear, I’m running the same 245/40/17 on the same 17x9 (can rotate these) but with a 12mm spacer and 1.6 degrees of camber. This puts the tire lip straight under the fender, and it also appears to clear with no spacer. I still have to pull the spring out and check full travel clearance to validate, but it looks promising given the tire stretch.

All told, happy with how all this is turning out, even though I’m giving up my favorite factory wheels.

[Slideways]

I committed yesterday and picked up a set of them. Overall they’re still light and ultimately I think this is the best balance of the above priorities. Bonus points that they’re the most affordable.

Also, it might be easier to get replacements or extras if you need them rather than the discontinued wheel.

[Bry5on]

The only 17 ET52 option that only has 7 in stock is the flow formed wheel - https://www.apexraceparts.com/store/...bmw-wheel.html

I committed yesterday and picked up a set of them. Overall they’re still light and ultimately I think this is the best balance of the above priorities. Bonus points that they’re the most affordable.

[Slideways]

The only 17 ET52 option that only has 7 in stock is the flow formed wheel - https://www.apexraceparts.com/store/...bmw-wheel.html

[Bry5on]

17x9 et42 Apex VS5RS (Or EC7R) with 5mm machined off the mounting flange and refinished in hypersilver?

You’ve got expensive taste! Interesting idea, I wonder how much meat there is left on the hub and whether this would end up compromising strength. Then you’ve got lug bolt length to think about too. I do have access to the equipment needed to perform the work..

[K-Dawg]

We’re both out of luck as Apex let me know today that these wheels are being phased out and they won’t be getting any more in. Just the one available.

Options now are:
1) Apex ARC-8 17x9 et52 17.2lb +5mm spacer (same poke, stock offset, but flat face)
2) Bimmerworld TA8s 17x9 et42 18.2lb (most stock looking wheel but will poke out 5mm more, making it look less stock)
3) Apex VS5RS 17x9 et42 16.2lb (lightest but doesn’t come in a silver finish and pokes out like the Bimmerworld wheels)

I believe all of these setups will clear 996 brakes from my limited research, and my current thought, after a lot of vacillating, is that minimizing poke will ultimately yield both the best steering feel and also the most OEM looking setup. We’re going for capable sleeper here.

Thoughts welcome.

17x9 et42 Apex VS5RS (Or EC7R) with 5mm machined off the mounting flange and refinished in hypersilver?

[Casa de Mesa]

Ahhh I see. Re-read your earlier post. I would have thought there are better options in 18's for the non-M fenders but I'm clearly showing my ignorance a tad!

Regardless, agree with maupineda this build is just spectacular. Have enjoyed following along so much.

[Bry5on]

Got it makes sense.

For what it's worth because I've been down this road, I've crunched the numbers A LOT on tire and wheel combos. The weight savings in a tire/wheel packing using the MPS4S is negligible from 18" down to 17". An MPS4S in 245/40R17 and 245/35R18 both weigh 22lbs with only a 0.1" difference in diameter. So it comes down to wheel selection. The overall weight savings is more dramatic when going from 19s to 18s.

https://www.tirerack.com/tires/Spec....+4S&isSEO=true

I went with 18's for all the functional reasons you stated. No spacers, good scrub radius, great brake clearance, still fairly compliant compared to 19s (actually, MUCH more compliant) and significantly reduced unsprung mass.

That said, based on your posts, you're **much** more technical than I am and clearly have an engineering background so you know what you're doing. I only stayed at a Holiday Inn Express recently.

With your fenders, I’d have gone 18” too, the easy button! You’re in good company here.

Kind of off topic, but what good canyon roads would you recommend around the Bay Area? Also it would be cool to meet some of you for drives or the likes. I moved to Hayward recently and brought my Z4M with me from Mexico.

btw, this touring build is just perfection from all angles. We’ll done

Thanks! There are a bunch of good roads up in Marin county, then there’s Skyline, Kings Mountain Rd, Bear Creek Rd, La Honda Rd, Pescadero Creek Rd and probably a bunch of others on the peninsula. Over by me in Berkeley there’s Pinehurst Rd (closest to you) and a couple quick jaunts in the Berkeley hills and near the reservoirs. All various pavement qualities, and generally the peninsula and Marin are better with more options.

Getting a drive together would be cool! You’re not the only one on here in the bay from MX either.

[maupineda]

Kind of off topic, but what good canyon roads would you recommend around the Bay Area? Also it would be cool to meet some of you for drives or the likes. I moved to Hayward recently and brought my Z4M with me from Mexico.

btw, this touring build is just perfection from all angles. We’ll done

[Casa de Mesa]

Got it makes sense.

For what it's worth because I've been down this road, I've crunched the numbers A LOT on tire and wheel combos. The weight savings in a tire/wheel packing using the MPS4S is negligible from 18" down to 17". An MPS4S in 245/40R17 and 245/35R18 both weigh 22lbs with only a 0.1" difference in diameter. So it comes down to wheel selection. The overall weight savings is more dramatic when going from 19s to 18s.

https://www.tirerack.com/tires/Spec.jsp?tireMake=Michelin&tireModel=Pilot+Sport+4S&isSEO=true

I went with 18's for all the functional reasons you stated. No spacers, good scrub radius, great brake clearance, still fairly compliant compared to 19s (actually, MUCH more compliant) and significantly reduced unsprung mass.

That said, based on your posts, you're **much** more technical than I am and clearly have an engineering background so you know what you're doing. I only stayed at a Holiday Inn Express recently.

[Bry5on]

These probably won't fit the brakes without spacers, might need centering rings and would make it look like Kevin's wagon had an evil twin, but some diamond black RGRs in 17s would look great IMO. I do prefer the standard silver 18" RGRs though.

hah, yeah the RGRs do look nice, I’ve just got my doubts that they’ll clear a set of fixed calipers. If I had M3 fender openings, I might consider 18s so I could still run enough sidewall, but the non-m is not so flexible.

Out of curiosity, why are you looking for 17s? Is it solely due to the weight or aesthetics? Or comfort of a taller sidewall?

Thanks, good question, a few reasons. Canyon roads and daily driving are what I’m optimizing this car for, and in my area the canyon roads are pretty poor quality so for both of those, I want a tall sidewall and a light weight wheel. Both of those things will allow the wheel to react quicker to road irregularities to maintain a more even contact patch pressure (read: more grip) while improving ride quality. I want to do all this while keeping the car with an appearance that is as unmodified as absolutely possible. Given the size of the fender opening and possible tire diameters, this pretty much limits you to 17” wheels.

I’m looking to stick with 245/40/17 square, ideally on a 9” wheel to best support the sidewall, as the PS4S is offered in this size. I’m on 17x8.5” et41 right now, with -2.15 camber and I’m happy with the grip and balance levels (50/50 car with 50/50 tire is nice and neutral) but I’d like to knock the scrub radius down another 5mm to get back to the stock M3 number range to nail the driver feedback. Going to a 9” wheel from an 8.5” should also help with feedback and response without giving up any ride quality. On top of that, I’d like to drop some unsprung weight (style 32 are around 24lb ea) and clear 996 brakes. Overall, a tall order over here with M3 track and non-m fenders. My math says I should be able to squeeze 17x9 et45-47, which the latter is the target.

[Casa de Mesa]

Out of curiosity, why are you looking for 17s? Is it solely due to the weight or aesthetics? Or comfort of a taller sidewall?