Max width of tires on a Non M Z3?

[edx1]

Looks/speedometer/odometer aside and the priority on corner handling and decreasing lap times, would some 16 x 9.5's all around running 255's (30, 40 or 50 profile) or wider work (265, 275?) and can 16's fit around brakes, etc? I'm looking to get some slicks for road coarse track days and I want to improve handling, avoid understeer and get better times for a 3.0 coupe. I'm not sure if there's a reason to stay with 17's if looks aren't the focus. I'm completely new to HPDE and been reading up on things so I'm curious and I don't see anyone discussing 16's or track times specifically when picking sizes. I'm also curious what the widest tire is that can fit on the front if going to a smaller diameter wheel. Or is there no reason to go wider than 245 on the front or rear with a 3.0? I'm currently running PSS and have just a slight bit of oversteer and no understeer with 225/245 (even on WOT coming out of corners) in third and fourth gear where I run on the track. The track has about 20 corners on it's minimum configuration and I can't keep my speed up where the spec miatas do (I know these are better cornering cars naturally... I just want to get closer to their times).

[SunzOut]

Looks/speedometer/odometer aside and the priority on corner handling and decreasing lap times, would some 16 x 9.5's all around running 255's (30, 40 or 50 profile) or wider work (265, 275?) and can 16's fit around brakes, etc? I'm looking to get some slicks for road coarse track days and I want to improve handling, avoid understeer and get better times for a 3.0 coupe. I'm not sure if there's a reason to stay with 17's if looks aren't the focus. I'm completely new to HPDE and been reading up on things so I'm curious and I don't see anyone discussing 16's or track times specifically when picking sizes. I'm also curious what the widest tire is that can fit on the front if going to a smaller diameter wheel. Or is there no reason to go wider than 245 on the front or rear with a 3.0? I'm currently running PSS and have just a slight bit of oversteer and no understeer with 225/245 (even on WOT coming out of corners) in third and fourth gear where I run on the track. The track has about 20 corners on it's minimum configuration and I can't keep my speed up where the spec miatas do (I know these are better cornering cars naturally... I just want to get closer to their times).

If your new to HPDE, more tire, just masks any issues/bad habits you may have and just leads to hitting solid objects faster, when something goes wrong.

A Z3 is perfectly fine on tires in the 225 to 255 width range, a square setup of 245's would be a nice setup if your looking to have a dedicated set. As for the 16 vs 17, stick with the 17. You have more tire choices as most 16" tires top out at 225, the 17's normally go to 255 or 265.

PS

Don't try to keep up with the Spec Miata's, many drivers in Faster cars than a Z3 have tried and failed...

[fallguy]

Im looking to fit these on my 3.0 coupe when my car shows up. We test fit them on a M roadster lastnight, the fronts were perfect (the M pushed the tires really close to the front bumper. The rears were too tucked over an inch for the M and they just touched the pinch weld on the rear trailing arm (could of been modded easy)

ill post pics when i get them on my car, i think the fronts will clear better than the M but i'm not to sure how much if any i will have to adjust on the rear (roll fenders/trim trailing arm pinch weld.)

Sumitomo HTRZ III
295/30R18 on 10.5 ET43 wheels
255/35R18 on 8.5 ET35 wheels

[rf900rkw]

You'll have clearance issues on the front unless you get M camber or greater.

[fallguy]

Ur probably right. This M had camber plates as well.

[edx1]

If your new to HPDE, more tire, just masks any issues/bad habits you may have and just leads to hitting solid objects faster, when something goes wrong.

A Z3 is perfectly fine on tires in the 225 to 255 width range, a square setup of 245's would be a nice setup if your looking to have a dedicated set. As for the 16 vs 17, stick with the 17. You have more tire choices as most 16" tires top out at 225, the 17's normally go to 255 or 265.

PS

Don't try to keep up with the Spec Miata's, many drivers in Faster cars than a Z3 have tried and failed...

I understand the concern about better tires masking driver errors until they are bigger errors, I definitely don't want to learn later. I've completed about 100 laps now (various cars) on the 2.2 mile tracks and had no offs yet, but one nice design feature of the track is there's only one turn in any of the configurations (which isn't always in play) that can wind up in a wall, otherwise it's all lots of gravel runoff and I've been on track with over a dozen other drivers who have gone off.

My goal is to look for a wheel now that I can grow into. Someone locally was selling a set of 16x9.5 wheels for a good price, but if 17" is where things are ideally at (and it sounds like if I'm buying used racing tires on the secondary market, I found out this afternoon that size doesn't matter much between 16, 17 and 18 and they all cost near the same). then maybe I should be looking for 17" wheels. According to charts, a 255 can still fit a 10" wide wheel, but I wonder if finding a good priced wheel that fits might be tough. 9" on a 255 though does sound pretty easy to fit on the front? Any idea if 9.5" running a 245 or 255 fits? Or maybe a 265? I'll start with some 245 or 255 all around before trying to increase tire widths, but I want to make sure I get a wheel width that will work for the best setup later on for the car... Thanks for the info, all greatly appreciated.

[z3papa]

The problem with 16" wheels and to a less extent 17" wheels, the tire sizes are limited. On a non-M, you can fit a 255/40-17 and on the rear you can fit up to a 275. There is a fair amount of inboard space in the rear. 255 square setup is what I used last with 17x9 Apex ARC-8. Worked like a charm and allowed me to rotate but did require camber plates up front and grippy tires will spit up debris where it cause rock chips if the areas are not protected.

[SunzOut]

"if I'm buying used racing tires on the secondary market" - again another bad idea on 2 counts....one your race tires again are bad to learn on. The newer 200 TWR street tires will be much better, for the same reasons you don't want crazy wide tires.

2nd they are used. Used race tires get heat cycled and you probably not buying a "set" so they can cause handling issues when part of your "set" are more worn or heat cycled.

I'd suggest a nice set of Kosei K1's (17x8.5) with some Dunlop ZII star specs (245/40R17), easy to fit, good grip and good life. (All in for around $1500 mounted and shipped from tirerack)


Or as Z3PAPA suggested the Apex ARC-8 (17x9) with a 245 or 255 tire. Going to be a little more pricey.

You can of course look out for a set of used wheels - but make sure to check for cracks etc.


PS

What brake pad setup are you running ?

[edx1]

I picked up the coupe earlier this year so I'm not sure what pads are on it, however I have had no issues of brake fading in 100+ degree temperatures at the track. I'm inclined to think a previous owner did auto-x or track based on some things I've noticed about the car including that the pads put off a lot of dust and are definitely not average pads.

I should be able to pick up sets of used, but the main reason for used is I'm not at a point where slightly different cycling or characteristics of the tire will matter, I'm just looking for low cost until I can warrant high prices. An example is I rolled the edge of my front right on the first session and that's just a horrible thing to do to brand new tires, so I'd prefer to do stupid things to cheap tires until I can avoid things like that. I don't have maintenance throttle down either which means the front tires are taking more of a beating during corners than they should.

On picking up debris, is anything needed more than the magnetic rear panel guards?

Also on the front camber plates, are those needed for all 255 or are they just needed for a certain offset on 17's or wheel width of 9"?

Also on used, I have a much better selection if I'm running 18's but I think 18's would be worse off, minus the fact that you need 18's if I were to do an e36 m3 brake swap.

[fallguy]

Sumitomo HTRZ III
295/30R18 on 10.5 ET43 wheels
255/35R18 on 8.5 ET35 wheels

No spacers
No fender rolling
BILSTEIN B12 KIT
one washer under the two lower strut mount bolts to add one more deg of camber

dont know if i really needed the extra camber, but not a bad idea with a large stagger setup. Photos are at full lock and i can also fit a finger between the strut and tire.

[healeydays]

I guess my question is what are you trying to get by putting a fat a tire on your Z3 as you can fit? I run 17" with 225 in front and 245 in the rear and the car handles great on the mountain windy roads I play on. I can see putting monster wide tires on the car if I was making it a drag car, but don't see the advantage on this one as setup.

BTW I too am running Sumitomo HTRZ III tires and love them.

[rf900rkw]

One degree of camber moves the top of the tire in about a 3/8".


As far as why? Because we can is the best answer. The gains are almost purely cosmetic. I'm boosted, so the added forward traction is a plus, but I could have done the same thing with gummy tires.

[fallguy]

For me... i plan on swapping in a LS with a T56, the LS might be boosted as well.

the tires were a really good deal IMO, and they came in the size i needed

[T.Dot E30]

Don't try to keep up with the Spec Miata's, many drivers in Faster cars than a Z3 have tried and failed...

Similar weight coupe with similar tires/driver can't take a Spec Miata? or are they too light and contain too much voodo magic?

[zellamay]

Pictures of same Z3 with stock Z4 M roadster wheels/tires: 225/45/18 front, 255/45/18 rear. Diameter is great, but offset causes occasional slight rubbing. This Z3 is for sale on Phoenix CL. I bought an M.IMG_0112.jpgIMG_0109.JPG

[BimmerBreaker]

I didnt know your z3 had z4m wheels... I just bought a set of those to put on my non-M coupe, maybe I will have to pop by sometime to see what they look like

[JeffyD]

Oh. Thats easy - itll look... good enough.. y'know, for a daily driver. I guessssss

[Maanski]

Love this thread. So informative. My question is: in order to get widest possible rear tires, what offset do I need if I don’t want to get any modifications done at all?? Only on 17” and 18”. I want the fronts to stay the same (225). I have a 1997 2.8 Z3.

also, what’s the best way to make my z3 sound louder and deeper while staying classy and not too crazy sounding??

Thanks!!

[sijray21]

Love this thread. So informative. My question is: in order to get widest possible rear tires, what offset do I need if I don’t want to get any modifications done at all?? Only on 17” and 18”. I want the fronts to stay the same (225). I have a 1997 2.8 Z3.

I'm not sure of the widest wheels, but i'm running 18x9.5 et35 wheels (no spacers) with 265/35/18 tires on my 99 2.8L (wider rear fenders) and there is still plenty of room; it's actually kind of amazing. i used https://www.willtheyfit.com/ for my fitment research.

also, what’s the best way to make my z3 sound louder and deeper while staying classy and not too crazy sounding??

I'm also interested in this. I was looking at some aftermarket exhausts or a shop to custom make one since there is limited options for non-m z3s and questions regarding the pre-1999 and post-1999 models (mine is right on the border - made on 1/1999), so i'm even more confused.

[solimans]

Love this thread. So informative. My question is: in order to get widest possible rear tires, what offset do I need if I don’t want to get any modifications done at all?? Only on 17” and 18”. I want the fronts to stay the same (225). I have a 1997 2.8 Z3.

also, what’s the best way to make my z3 sound louder and deeper while staying classy and not too crazy sounding??

Thanks!!

Yes sir, not sure on the widest tire. What helped me when sizing...

Figure out what you have now. Back spacing, off set, and front spacing. Some good videos on YouTube re this. You have to do math n stuff :/

Then note how much room you have to go bigger and add that to your current dimensions.

Note the 2.8 engine really doesn’t need that much tire in the back (I have a 2.8)...but just for looks that’s a different thing


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[rf900rkw]

Yes sir, not sure on the widest tire. What helped me when sizing...

Figure out what you have now. Back spacing, off set, and front spacing. Some good videos on YouTube re this. You have to do math n stuff :/

Then note how much room you have to go bigger and add that to your current dimensions.

Note the 2.8 engine really doesn’t need that much tire in the back (I have a 2.8)...but just for looks that’s a different thing


Sent from my iPhone using Tapatalk

Oh, the horror!!!!

[solimans]

Oh, the horror!!!!

Lol!! Math and electrical stuff. Two things that “need improvement” for me


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[Maanski]

Is your car m or non m? Also what offsets fo you have front and back now?

[solimans]

Is your car m or non m? Also what offsets fo you have front and back now?

Non-m. Currently have ET 38.7 rear, and ET 37 front. That’s with st coilovers.

This site is helpful for specs on stock rims

http://www.bmwstylewheels.com



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[bionicbelly]

Don't try to keep up with the Spec Miata's, many drivers in Faster cars than a Z3 have tried and failed...

Um, any Z3* on decent/equal tires should be able to be faster than a spec miata. The gap will vary by track, but if you are getting beaten by a spec miata, it is not because of the cars. Granted, a lot of times the gap is smaller than it should be, SM's are weirdly fast.

Edit: *six cylinder Z3.

For reference, I have driven a SM (regional champ's car, so a good one), and My 3.0 coupe on two of the same tracks. Iowa speedway, and RPM. I think it was ~2.5 seconds quicker at IS, and about 3-3.5 seconds quicker at RPM.