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View Full Version : Looking for opinions on a square setup



tkundhi
02-23-2014, 09:07 PM
I'm investing options for a square setup for summer tires. Being able to rotate is a must. The tires will be extreme or max performance Michelin, Bridgestone, Continental or Dunlops. They will be used on the street for 7 months plus 12-16 track days per year. Suspension is 100% stock. I'm willing to consider spacers and fender rolling. But prefer not to do either. Here's what I'm considering. I'm interested if anyone has these fitment with these sized tires. Links to pictures would be appreciated.

VMR V710 18x8.5 et45 22.5lb w/ 245/40 18 or 255/35 18
VMR VB3 18x8.5 et40 23lb w/ 245/40 18 or 255/35 18
Avant Garde Type M310 18x9 et38 23.5lb w/ 245/40 18 or 255/35 18
Avant Garde Type M359 18x8.5 et35 23.5lb w/ 245/40 18 or 255/35 18
APEX EC7 18x9 et42 20.75lb w/ 245/40 18 or 255/35 18
APEX EC7 18x8.5 et35 20.1lb w/ 245/40 18 or 255/35 18
APEX ARC8 17x9 et42 17.25lb w/ 255/40 17
D-Force LTW5 17x9 et41 16.6 lb w/ 255/40 17

Thx,

t.

derbo
02-23-2014, 10:14 PM
ARC8 or LTW5 gets my vote.

Tire wise with 16 track days a year, I would pick,

Dunlop Star Spec II, Hankook RS3, or Bridgestone RE11A as the main 3 to look for a great track tire that is still somewhat streetable.

tkundhi
02-23-2014, 10:44 PM
Thanks Derek. FWIW, I already own the LTW5s, I'm just not sure how I feel about them on the ZHP. I like the centers of the other multiple spoke wheels more than the ARC8. What fitment are your ARC8s?

I've gone with the Dunlops for my last two sets. First the Star Spec I, then Star Spec II. They got a little loud towards the end of year two. I was thinking about trying the Pilot Super Sports or the Contis. But that decision will come after the wheels. Not all the tires are available in all the sizes.

The ZHP is primarily my wife's DD. But it will be my track car for at least this year.

t.

JKO_ZHP
02-23-2014, 11:39 PM
No Avant Garde M359s? I would not recommend VMRs for track and daily driving use, at least not after what I heard: VMR wheels are gravity-cast. That is ok but all BMW wheels are at least low-pressure cast (a step above gravity cast) because it is their standard. It would imply that our stock wheels are already stronger than VMR wheels.

Avant Gardes are low-pressure cast, so they are at least on par with our factory style 135 BMW wheels.

JupiterBMW
02-24-2014, 05:01 AM
JKO raises a good point about wheel build as well... I've not heard the best thing about VMRs in terms of this either. For what its worth, I've got the AG M359s...

Also, in terms of going square. I'm square right now... My specs are as follows...

18x8.5, ET35... The wheels aren't that wide, but its a fair amount of offset, especially up front. Overall, my wheels stick out 15mm more than stock in the back, and about 18mm up front, which is considerable. I'm running 245/35-18s all around, which is a good blend between the stock sizes. Considerable rubber up front, without being too little out back.

In terms of suspension, I'm running H&R springs up front, but otherwise, all stock. The car doesn't rub at all, but I've already rolled my fenders. Personally, I would do that if I were you, and shave the rear bumper bolts in the rear wheel wells. It'll help quite a bit.

Some of the choices you've posted sound pretty good, others will definitely need some rolling to make them fit, but all is possible.

As for the look, check out my sig for a link to my project thread. I just posted some updated pics, so check it out for an idea of what it'll look like.


Good luck. :thumbsup

cakM3
02-24-2014, 05:04 AM
ARC8 or LTW5 gets my vote.

Tire wise with 16 track days a year, I would pick,

Dunlop Star Spec II, Hankook RS3, or Bridgestone RE11A as the main 3 to look for a great track tire that is still somewhat streetable.

I agree with Derek here :thumbsup

Crickett
02-24-2014, 06:44 AM
Knowledgable folks in here, t. I would also recommend playing around with the calculator at WillTheyFit.com (http://www.willtheyfit.com/) as you consider different sizes/offsets/spacers/etc..

BTW, I am also square on 4x 18x8" ET47 stock 135Ms, 245/35ZR18 Michelin Pilot Sport A/S 3, stock suspension, and no fender modification.

danewilson77
02-24-2014, 08:07 AM
As for the look, check out my sig...

Please photoshop "330" for the address on your mail box.

Thank you.

Sent from my SCH-I545 using Tapatalk

ELCID86
02-24-2014, 08:09 AM
Please photoshop "330" for the address on your mail box.

Thank you.

Sent from my SCH-I545 using Tapatalk

I was thinking #3 Dinan, but I like it!

johnrando
02-24-2014, 08:20 AM
Please photoshop "330" for the address on your mail box.

Thank you.

Sent from my SCH-I545 using Tapatalk

Ah, great idea! Or, move down the street. :)

derbo
02-24-2014, 09:03 AM
Thanks Derek. FWIW, I already own the LTW5s, I'm just not sure how I feel about them on the ZHP. I like the centers of the other multiple spoke wheels more than the ARC8. What fitment are your ARC8s?

I've gone with the Dunlops for my last two sets. First the Star Spec I, then Star Spec II. They got a little loud towards the end of year two. I was thinking about trying the Pilot Super Sports or the Contis. But that decision will come after the wheels. Not all the tires are available in all the sizes.

The ZHP is primarily my wife's DD. But it will be my track car for at least this year.

t.
T,

My ARC8 fitment is 17x8.5 +42 245/40/17 Star Spec 1s. I will be replacing them with StarspecII 255/40/17 when these tires die out.

With regards to the wheels, Bcleaver has D force wheels as well as LivesNearCosto if I recall. I personally don't like the look of them but there is a high attraction to the wheels because of how easy it is to clean them. When I look for track wheels, I look for weight, durability, price as my priorities. Looks, size are usually at the end. ARC8 and LTW5 have been proven to be durable enough by many hardcore enthusiasts that durability isn't much of a concern when looking at these styles. I like the look for ARC8 better than the LTW5 and at the same price point, I chose the one I like more. :)

I'm sure when Dunlop was developing extreme performance tires, they were not considering tire noise as priority! FYI, 18s 255 performance tires are close to double the 17s 255 tire prices if that is a concern to you. If you are definitely tracking it this year, it might be something to think about since Tires/Brakes are the most wear/tear items that are constantly replaced. I don't believe the Continental DW or Michelin PSS are on par with the RS3, StarSpecs or RE11 in terms of traction performance. They will most likely be better at road noise, treadwear and rain performance. Personally I would chose RS3, StarSpec or RE11 for dry traction since that's my priority for track tire setup. If it was a wet track setup, I may consider the PSS.

Hope this helps!



Bcleaver's build thread (more recent pages have the wheels installed) --> http://www.zhpmafia.com/forums/showthread.php?1859-330-zhp-SCCA-Solo-STX-build/

https://lh3.googleusercontent.com/-ofYamsJJCTQ/UcuYuyhwcvI/AAAAAAABFVk/F0nFxDjiH-E/s800/1000807_10151570069521785_68876673_n.jpg

JupiterBMW
02-24-2014, 09:06 AM
Ah, great idea! Or, move down the street. :)

Hmm, I'd have to move to a different street... Looking to see what house is at that number... :shifty

LivesNearCostco
02-24-2014, 09:59 AM
Echoing derbo's comment... in the same size the Dforce LTW5 are slightly lighter than the Apex Arc-8 and easier to clean, but the Arc-8 has a reputation of being a little stronger. Apex has another wheel (EC7?) that is a little heavier and stronger than the Arc-8. But I have only driven the LTW5 wheels.

From personal experience and listening to others at track/AutoX, the Continental ExtremeDW are good in the dry but not as good as Star Spec, R-S3, or RE-11. The ExtremeDW is reputed to be the best street tire for rain AutoX or track than any of those, but I never autocrossed them in the rain. I have Pilot SuperSport now on my OEM wheels but only tracked them for one session and never autocrossed them, so I cannot say yet how they compare. It does seem that none of the most competitive autocrossers on street tires use PSS--they all have Star Specs, R-S3, BFG Rival, or some Toyo model.

tkundhi
02-25-2014, 02:28 PM
Jon, what tires are you using on your AG M359s?

t.

tkundhi
02-25-2014, 03:08 PM
OK, so here's were I am with my decision. I'm rethinking the square setup all together. I had a lengthy conversation with a good buddy of mine that is also a fellow ZHP owner. He use to be an automotive engineer so he really understands vehicle dynamics. He has helped setup grand am cars. He is running 235/40 18 & 255/35 18 on his ZHP (100% stock suspension) and feels it is pretty neutral on street/track. Only issue is that at times on the street the DSC kicks in really early. This is because the increased front tire height. This introduces a 1% error between the front and rear wheels. So the system engages earlier than the stock wheel setup. He has also used a 235/40 17 square setup at times. On the square setup he said the car was much more tail happy. Now this isn't a concern for me but he pointed out is may not be desirable to my wife. He knows her pretty well.

Our ZHP is primarily my wife's DD. It's going to be my track car until I get my other cars sorted out. So all out track performance is secondary. My objectives are nice appearance, reasonable weight (must be less than stock) and a wheel tire combo that I can use at the track. That is why I wanted the square setup, so I could rotate tires to even out the wear. But maybe I should forgo tire rotation.

My wife is comfortable driving my E36 M3 with a 255/40 17 square setup. That car came stock with a 225/45 17 & 245/40 17 staggered combo. The square setup made it neutral not too loose.

Has anyone run a 245 square setup at the track? What about a 255 square setup? Was the car neutral or more prone to oversteer? I'd appreciate your thoughts. Keep in mind my suspension is 100% stock and will stay that way. The one thing I will probably do is add a little camber by knocking out the alignment pins in the strut.

I'm leaning towards the AG M359 or APEX EC7 wheel options. Both look nice and are lighter than stock.

Thanks,

t.

derbo
02-25-2014, 04:10 PM
Unfortunately I never pushed my car on 100% stock suspension so I am unaware how a square setup will change the factory handling.

I currently have my zhp on 448lbs/560lbs coilover with 245/40/17 square setup.

Other variables I have:
Camber F -3, R -2.2
UUC Front sway bar set to full stiff
Factory rear M3 bar
M3 LSD/rear end

At this point, my car feels very neutral (to me at least with a hint of understeer from the full stiff in the front)

sillieidiot
02-25-2014, 04:24 PM
yeah that's weird. going to a square setup should make it more neutral since at 100% stock, your car is setup for understeer. iono if it makes it oversteer even more though. i went for a staggered style 71s (since i don't have a zhp) to squared arc8s 18x9.5 with ast suspension so yeah. with my 100% stock setup, i definitely understeered way more when i pushed it. on my new setup, i still have a bit of understeer, but way less than stock. i need some sways.

JupiterBMW
02-25-2014, 04:26 PM
Jon, what tires are you using on your AG M359s?

t.

I'm running Yokohama S-Drives, 245/35-18


iPhone 5S. Tapatalk Pro. BOOM

Avetiso
02-25-2014, 04:56 PM
ARC 8, as concave as you can go. Looks awesome and very functional.

scooby24
02-26-2014, 01:15 PM
I have 245/35R18 on 18x9 et 37 square, and it's as neutral as it can be.

LivesNearCostco
02-26-2014, 03:32 PM
I ran 255 and 245 square at the track and AutoX. With a nearly stock suspension--just knocking out the camber pins as you said--it understeered a lot, but not as much as with stock camber and staggered tires. Then I added more negative front camber (first -2.8 then -3.0), then coilovers with stiffer springs. I was closer to neutral but still understeered. At this point I could still get the back end to come around by turning DSC completely off and lifting off the gas in a corner. Sometimes I also put worn Bridgestone RE-760 255mm tires on back and 245mm Continental ExtremDW tires on front, and then the back really liked to come around if I lifted in a corner! Finally I added stiffer front swaybar, more negative camber (about -3.3), and more positive caster -- now the car feels pretty neutral to me on square tires.

There are definitely cars that do better with a staggered setup, typically high HP cars (like E46 or E90 M3) or rear-engine cars like the Porsche 911--some of those have like 245mm front, 315mm rear tires! But I dont' think a ZHP with stock engine is one of those.

Also neutral handling can be subjective. Once I had square tires and coilovers with fatter front swaybar, I thought it was neutral, but an instructor riding with me (who happens to be a national-level autocrosser) told me my car was still understeering.


Has anyone run a 245 square setup at the track? What about a 255 square setup? Was the car neutral or more prone to oversteer? I'd appreciate your thoughts. Keep in mind my suspension is 100% stock and will stay that way. The one thing I will probably do is add a little camber by knocking out the alignment pins in the strut.

tkundhi
02-26-2014, 04:09 PM
Thanks for all the feedback guys. I'm fine with a little understeer or oversteer. Of course neutral is preferred but I can adapt my driving. I'm instructing not racing. My concern has been how much of the factory understeer goes away. Particularly if going 245 all around. That is 20mm more grip up front with 10mm less grip in the rear. I didn't want the car to become so different from stock that it puts my wife in an uncomfortable situation. After all, this is her car.

Sounds like the car's inherent understeer will remain. This weekend I'm going to test fit my D-Force wheels with some spacers just to check clearances. If all's good I'm thinking 18x8.5 et35 with 245/35 18s. I like the APEC EC7s because of the lower weight. But Jon's wheels look oh so sweet! Maybe I'll let my boss decide. :)

t.

LivesNearCostco
02-26-2014, 04:20 PM
Tell her to stop turning off DSC! Just kidding. I'm a mediocre autocrosser but was coaching one first-timer and one 5th-timer last Sunday. Both had M cars (E90 M3 and E39 M5). At one point I was encouraging them to use more gas accelerating out of a turn, but I forgot that M cars have a lot more torque, and the E90 M3 guy had just turned off DSC. Even with the stock staggered setup (or partly because they were street tires), one driver spun and the other had a big tank slapper, because I coached them to use too much gas too soon.

tkundhi
02-26-2014, 05:34 PM
About 10 years ago. My second school as an instructor I get assigned a novice student in a Viper. Plus it's raining. I wasn't comfortable as I'd seen many Vipers spin in the dry with more experienced drivers. I traded students with a much more experienced instructor. The Viper's torque intimidated me.


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derbo
02-26-2014, 05:59 PM
I would imagine the understeer will still remain. Adjustable Sway bars can alter than too! :) I actually has a set of UUC sway bars before I switched to a squared setup.