Can I break my 275s loose...

[e36widelip]

Updated 01/01/07 post#26 scroll down for more pics

Got my tein coilovers intstalled, got her raked, and installed my new rims and tires

http://i22.photobucket.com/albums/b337/e36_widelip/DSC04907_edited1.jpg

[e36widelip]

http://i22.photobucket.com/albums/b337/e36_widelip/DSC04911_edited.jpghttp://i22.photobucket.com/albums/b337/e36_widelip/DSC04065.jpg

[Robstah]

Yes, yes you can. Love the rims. :thumbup:

[bmwperson]

what offset wheel? and what did you do to the fenders?

[eurotekm3]

DAM! thats a phat lip !!!:eek: Those are my rims...:shifty
U need a WBody or a new wider rear bumper.. it will make your car look
10X better.IMO:buttrock

[5mall5nail5]

Look like Kumho 712s. My car supercharged broke my 255/40 17x10's loose :)

[dmb882]

Beautiful wheels! You going to roll the fenders?

[HyperHoHo]

Looks good! No traction on that wheel/tire setup though...

[e36widelip]

what offset wheel? and what did you do to the fenders?

fenders are already rolled

iForged Aeros brushed aluminum

fronts 19x8et41 235's 1 1/2 lip
rears 19x10et38 275's 4" lip


Look like Kumho 712s. My car supercharged broke my 255/40 17x10's loose :)

toyo T-1s


DAM! thats a phat lip !!!:eek: Those are my rims...:shifty
U need a WBody or a new wider rear bumper.. it will make your car look 10X better.IMO:buttrock

i could always put my reiger kit on

http://i22.photobucket.com/albums/b337/e36_widelip/DSC04047.jpg
http://i22.photobucket.com/albums/b337/e36_widelip/DSC04049.jpg
http://i22.photobucket.com/albums/b337/e36_widelip/DSC04062.jpg

i think it already sits pretty as it is

http://i22.photobucket.com/albums/b337/e36_widelip/DSC04941_edited.jpg
http://i22.photobucket.com/albums/b337/e36_widelip/DSC04917_edited.jpg

excuse the crap pictures

[///36M]

can you divulge how much negative camber you are running?

[highboostingm3]

When you do the Rieger flares, please:
-do not include the side skirt portion...just stop the flare at the top of the side skirt.
-shave the mold on the flare since it is for an M3 mold and wouldn't match an M3 mold really anyways, then have your guy add mold to copy the actual molding you have so it flows and matches correctly.
-either that or shave the mold completely.

Every Rieger flare I have seen doesn't look quite right when the flare is brought down into the side skirt.

This is the best Rieger setup I have seen. Flare only to top of side skirt and no mold FTW. This is Excidium28's car.

http://img187.imageshack.us/img187/9188/newsighx3.jpg

[e36widelip]

can you divulge how much negative camber you are running?

stock

[RSF5]

stock

damn that certainly does not look stock.

[///36M]

+ 10 million... i realize picture's deceive, but it looks a hell of a lot more than the 1.8 im running.

[m3j0n]

taht looks great!.. is it possible to purchase only the rear flares? and would it look weird if you ran the stock bumper with them?

[e36widelip]

When you do the Rieger flares, please:
-do not include the side skirt portion...just stop the flare at the top of the side skirt.
-shave the mold on the flare since it is for an M3 mold and wouldn't match an M3 mold really anyways,

hey cam,

thanks for the input..but i have my M moldings on and i got some top secret plans for that side skirt problem. Just have to wait and see...no teasers

[3literheater]

i thought that Excidium28's car just had the Reiger side skirts not the flares?

[Matt]

I think pretty much any car can break pretty much any width 712s loose.

:rofl

[highboostingm3]

i thought that Excidium28's car just had the Reiger side skirts not the flares?
If you look closely, he actually has stock M3 side skirts. The flares are totally molded so it looks like his car was always like that since it was done so smoothly. he also has the Rieger front bumper and I am pretty sure rear bumper. He is almost done with his GT35R top-mount. Car will be a monster.

[milKt]

Got my tein coilovers intstalled, got her raked, and installed my new rims and tires

Which model Tein dampers?

basic, SS or SS-P

With/without sapcers?

Tanx

[ZimDoc]

The car cools great and dont go with those flares. The stock body with huge wheels/tires looks great.

Keep up the good work!!!

[fritzintn]

I know it's probably crass to ask, but I think most of us are thinking it. Why'd you choose to spend quite a bit of time/money/effort stuffing 275s under your car as opposed to just getting stickeir rubber?

Either way it looks hot and I suspect that was the primary goal. (+1 on the 712s sucking :))

[3literheater]

If you look closely, he actually has stock M3 side skirts. The flares are totally molded so it looks like his car was always like that since it was done so smoothly. he also has the Rieger front bumper and I am pretty sure rear bumper. He is almost done with his GT35R top-mount. Car will be a monster.
Those are not stock side skirts, they are Rieger ones with the stock jack hole molded in. I know this because I asked him about it.

Here is his car:
http://i95.photobucket.com/albums/l125/excidium28/DSC01482.jpg (http://i95.photobucket.com/albums/l125/excidium28/DSC01482.jpg)


Are you sure he has the Rieger flares because it looks like he just has pulled fenders to me?

[DANGERFOOT]

shouldnt be too hard to brake em loose, i brake my 255s loose all doay long in first and second gear and im NA

[techno550]

traction is independent of tire width.

[e36widelip]

Which model Tein dampers?

basic, SS or SS-P

With/without sapcers?

Tanx

Tein basic without spacers

[e36widelip]

I think pretty much any car can break pretty much any width 712s loose.

:rofl


I know it's probably crass to ask, but I think most of us are thinking it. Why'd you choose to spend quite a bit of time/money/effort stuffing 275s under your car as opposed to just getting stickeir rubber?

Either way it looks hot and I suspect that was the primary goal. (+1 on the 712s sucking :))

i don't ride on kumhos....they're Toyo T1's...with them being 275's, I think I have a pretty sticky rear end.

[e36widelip]

traction is independent of tire width.

maybe it'll help me create load for my t70 p-trim AR.84:D

[e36widelip]

Had some decent light outside, here's some better pictures:

http://i22.photobucket.com/albums/b337/e36_widelip/DSC05002.jpghttp://i22.photobucket.com/albums/b337/e36_widelip/DSC04999.jpg

[e36widelip]

Some more pics:

http://i22.photobucket.com/albums/b337/e36_widelip/DSC04979.jpghttp://i22.photobucket.com/albums/b337/e36_widelip/DSC04970.jpg

[e36widelip]

Some more pics:

http://i22.photobucket.com/albums/b337/e36_widelip/DSC04987.jpg
http://i22.photobucket.com/albums/b337/e36_widelip/DSC04976.jpg
http://i22.photobucket.com/albums/b337/e36_widelip/DSC05006.jpg

[e36widelip]

and last of the bunch:

http://i22.photobucket.com/albums/b337/e36_widelip/DSC04995.jpg
http://i22.photobucket.com/albums/b337/e36_widelip/DSC05005.jpg

[wushucivic]

traction is independent of tire width.

i've seen your explanation before about how two different sized tires (everything else being the same) on the same car will have the same amount of material touching the ground, and they will just have a different shaped contact patch, but why is it that wider tires seem to give more grip that thinner ones? if i take my 225s up front and switch them with the 245s in back i can break them loose easier/sooner than the 245s.

[highboostingm3]

i've seen your explanation before about how two different sized tires (everything else being the same) on the same car will have the same amount of material touching the ground, and they will just have a different shaped contact patch, but why is it that wider tires seem to give more grip that thinner ones? if i take my 225s up front and switch them with the 245s in back i can break them loose easier/sooner than the 245s.
He has said it's only because they are heavier tires.

[///36M]

OP: So you dont rub at all?

[Eric BMW]

Thats a lot of unsprung weight. Looks sweet. Rieger Infinity II widebody now!

[dmb882]

I wouldn't even go widebody. The rear's look nasty crammed in there!!

[wushucivic]

He has said it's only because they are heavier tires.

gotcha. thanks cameron.

[resisTm3]

your car looks amazing, those are probably my favorite wheels on a m3.

what exhaust setup are you running?

[promp3]

what kind of muffler is that? is it a 3'' inlet? and if you do go wide body sell me that rear bumper!

you car with those fat meats and stock fenders is like a body builder wearing one of those muscle shirts with the short little arms so there bulging muscles look bigger. putting flares on will make things look more balenced but it looks good eather way. I have 255's on 9.5's in back and I thought I was cutting it close! very nice!

[paul e]

i've seen your explanation before about how two different sized tires (everything else being the same) on the same car will have the same amount of material touching the ground, and they will just have a different shaped contact patch, but why is it that wider tires seem to give more grip that thinner ones? if i take my 225s up front and switch them with the 245s in back i can break them loose easier/sooner than the 245s.

I think we can all agree that its the Area of the contact patch, ie, its length multiplied by its width, which tells us how much rubber meets the road. I just finished reading an article which states that the area of the contact patch can be determined by dividing the Car's weight by the air pressure in the tires.. For instance, its probably not too far off to determine that many of our cars weigh around 3200 lbs, and use about 32 lbs of air in the tire(s). Hence, the contact patch at each corner is about 100 sq inches. The length and width of that contact patch will vary according to tire size, but not its area. AT least, thats according to this article: http://auto.howstuffworks.com/question506.htm

Intuitively this makes sense. I mean, we dont really think that the same tire when installed on an S2000 and on a 4500 behemouth will present the same sized contact patch do we? So clearly the weight of the vehicle has an impact on contact patch size. The formula shows it, but so does intuition and logic. The part many of us have a tougher time coming to grips with is, does a wide squat tire really give us no more traction than a skinny tire with high side walls? We could sure save alot of money if the skinnier tires really gave us the same size contact patch couldnt we?! But according to the formula, and according to what Techno550 is purported to have said (which seems to support what the formula is telling us), contact patch size really is independant of tire size!! So, what.. its all Cosmetic?! Damn!!

[3literheater]

I think we can all agree that its the Area of the contact patch, ie, its length multiplied by its width, which tells us how much rubber meets the road. I just finished reading an article which states that the area of the contact patch can be determined by dividing the Car's weight by the air pressure in the tires.. For instance, its probably not too far off to determine that many of our cars weigh around 3200 lbs, and use about 32 lbs of air in the tire(s). Hence, the contact patch at each corner is about 100 sq inches. The length and width of that contact patch will vary according to tire size, but not its area. AT least, thats according to this article: http://auto.howstuffworks.com/question506.htm

Intuitively this makes sense. I mean, we dont really think that the same tire when installed on an S2000 and on a 4500 behemouth will present the same sized contact patch do we? So clearly the weight of the vehicle has an impact on contact patch size. The formula shows it, but so does intuition and logic. The part many of us have a tougher time coming to grips with is, does a wide squat tire really give us no more traction than a skinny tire with high side walls? We could sure save alot of money if the skinnier tires really gave us the same size contact patch couldnt we?! But according to the formula, and according to what Techno550 is purported to have said (which seems to support what the formula is telling us), contact patch size really is independant of tire size!! So, what.. its all Cosmetic?! Damn!!

What about when you go to street slicks or R compound? You definitely have more grip with those. So wouldn't increasing the amount of rubber thats on the ground with a wider tire do the same thing?

The thing that isn't in this equation is the fact that not every tire of the same size puts down the same patch and it also doesn't include the rain channels that are in the tires. Also there are many different compounds of rubber that would aid in more traction. This doesn't seem to make sense because racecars have very little weight and huge tires. So you are saying that if the racecars put on smaller tires that they would put down the same track times? And the equation is also missing weight transfer. You will definitely have more grip with wider tires in a corner then with skinny ones.

[techno550]

What about when you go to street slicks or R compound? You definitely have more grip with those. So wouldn't increasing the amount of rubber thats on the ground with a wider tire do the same thing?


The thing that isn't in this equation is the fact that not every tire of the same size puts down the same patch and it also doesn't include the rain channels that are in the tires. Also there are many different compounds of rubber that would aid in more traction. This doesn't seem to make sense because racecars have very little weight and huge tires. So you are saying that if the racecars put on smaller tires that they would put down the same track times? And the equation is also missing weight transfer. You will definitely have more grip with wider tires in a corner then with skinny ones.
When you go to R compounds you get the same contact area still, but a stickier compound. Same goes for grooves in the tire, the contact area is still unchanged. The shape is changed though. The usual reason for them not having grooves is a tread stability thing too, which is a tread life and tire life issue mostly.

Race cars have wide tires because tire surface area is a heat shed thing. You also need to account for the loads the tires see. An 1900 lb LMP car isn't just 1900 lbs devided between 4 tires, its 1900 lbs of static load + occasionally up to 10,000 lbs of aero load, distributed unevenly among 4 tires.

How do you "definately" get more grip with wider tires in a corner?

As a brain teaser for those who have been following along with the tire physics bit for a lot longer, here's a fun one. If surface area directly relates to grip in a positive way, meaning more surface area means more grip, then it would reason that less tire pressure equates to more grip. However, its usually seen that increased tire pressure means more grip. Is this not counter to the previous statement, as increased pressure means decreased contact area? hmm... :devillook

[Matt]

The amount of tire contant patch doesn't just depend on airpressure, it depends on the construction of the tire, also.

As for pressure and grip being directly related, does that have to do with the spring rate in the tire increasing so the tread gets worked harder?

[paul e]

Matt, Techno... good stuff. file under topics which tend to run 'counter-intuitive'! Maybe it should be suggested to the Myth Exploders on the Discovery channel :D

[3literheater]

I am not sure about this topic, so thats why I am asking questions. I do know if you put bicycle tires on my car it would have severely less traction then my car with 245's. Also what about when the car accelerates and all of the weight is thrown to the rear tires? Wouldn't that throw the equation out the window?? If you have more weight on the back tires then all of a sudden the wider tire would come into play...correct? Just like when you are in a corner and all of the weight is thrown to one side of the car. So with the 3200 lbs divided by two tires instead of four, with a wider tire you have the ability to put down a larger patch and therefore have more grip.

So why do drag cars have huge tires in the rear? If the weight transfer and wide tire=grip come into play?

In the link that paul e provided all that it talks about is the length of the patch according to the weight of the car. So basically when you make the tire wider the length doesn't change, just the width. You basically make the contact patch larger only by the width and not the length because your car doesn't weight any more then it did before you put the wider tires on. You will have a larger patch though.

[dmb882]

When you go to R compounds you get the same contact area still, but a stickier compound. Same goes for grooves in the tire, the contact area is still unchanged. The shape is changed though. The usual reason for them not having grooves is a tread stability thing too, which is a tread life and tire life issue mostly.

Race cars have wide tires because tire surface area is a heat shed thing. You also need to account for the loads the tires see. An 1900 lb LMP car isn't just 1900 lbs devided between 4 tires, its 1900 lbs of static load + occasionally up to 10,000 lbs of aero load, distributed unevenly among 4 tires.

How do you "definately" get more grip with wider tires in a corner?

As a brain teaser for those who have been following along with the tire physics bit for a lot longer, here's a fun one. If surface area directly relates to grip in a positive way, meaning more surface area means more grip, then it would reason that less tire pressure equates to more grip. However, its usually seen that increased tire pressure means more grip. Is this not counter to the previous statement, as increased pressure means decreased contact area? hmm... :devillook


For the teaser:
It depends on the tire, sidewall, and use. If you are drag racing you want a tall tire, high sidewall, width, sticky compound, w/ lower air pressure and it is all of these things that increase the "footprint" which provides more traction/grip. Not really sure but in road racing I'm sure you would want tallest possible tire in reason to not affect gear too much, plenty of width, and the right amount of sidewall, with proper pressure to again get the largest footprint.

That really doesn't answer the question. I guess once you find the optimum pressure if you are below it adding pressure would help and if you are above it lowering pressure would help.

[SpasticDwarf]

thats a really stupid argument to say that wider tires dont increase your contact patch.

[dubseven]

Im sure you can.

[kowalski]

As a brain teaser for those who have been following along with the tire physics bit for a lot longer, here's a fun one. If surface area directly relates to grip in a positive way, meaning more surface area means more grip, then it would reason that less tire pressure equates to more grip. However, its usually seen that increased tire pressure means more grip. Is this not counter to the previous statement, as increased pressure means decreased contact area? hmm... :devillook

probably has to do with once the tires warm up they expand causing a drop in pressure. And i would not say that an increase in pressure means more grip because thats only to a certain extent. there is an optimum pressure for every tire where the tread is flat rather then shaped in a U contact or the reverse of that. You will notice over inflated tires will have 2 streaks per tire when doing a burnout...

[rippinbmwm3]

just my 2 cents...if you have a smaller tire wouldnt you have more weight per square inch which should give you more traction right??? like 3literheater said i know bicycle tires would give no traction so small within reason? like i said just my 2 cents.

[highboostingm3]

The way to test it would be to have two sets of tires. One wider than the other. Have the same guy with same car do the 1320 5 times with one set and then 5 times with the other with the exact same launch technique. Whichever has the lowest average 60ft wins! That will end this debate.

[Matt]

thats a really stupid argument to say that wider tires dont increase your contact patch.

Not really.

[techno550]

thats a really stupid argument to say that wider tires dont increase your contact patch.
:rolleyes

The way to test it would be to have two sets of tires. One wider than the other. Have the same guy with same car do the 1320 5 times with one set and then 5 times with the other with the exact same launch technique. Whichever has the lowest average 60ft wins! That will end this debate.

Still quite a few other variables change there. You can't change tire width and not change the vertical sping rate of the tire, so different spring and damper settings owuld be needed in order to hold all else equal.

As for "proof", there are plenty of teams that have run a narrower tire and gone faster. So its as simple as needing the right size tire for the application. Too narrow is not good, and too wide is not good.

For the grip side of things, its equal. Tire width is balancing weight and heat shed management (surface area).

[SiGmA]

Michael, what width of a quality street (non-R) compound tire would you recommend for a e36 coupe, estimated weight at 3200lbs? I think I have seen posted before that a 235 or 245 is going to give you ideal tread contract, but maybe not.

[techno550]

Michael, what width of a quality street (non-R) compound tire would you recommend for a e36 coupe, estimated weight at 3200lbs? I think I have seen posted before that a 235 or 245 is going to give you ideal tread contract, but maybe not.

The compound plays the biggest role, and the tire construction and suspension need to work together, so there's not a single *best* tire as a generic choice. Tire widths tend to vary slightly from brand to brand as well.

Something in the 225-245 range would be a good match for the E36 in the 2700-3400 lb range. Wider/narrower than that range is acceptable as well depending on the tire and use. I run 235's on 17x8.5's.

[daaaaainguyen]

man your rims are look great!..but i think you should go wingless =D

[highboostingm3]

The compound plays the biggest role, and the tire construction and suspension need to work together, so there's not a single *best* tire as a generic choice. Tire widths tend to vary slightly from brand to brand as well.

Something in the 225-245 range would be a good match for the E36 in the 2700-3400 lb range. Wider/narrower than that range is acceptable as well depending on the tire and use. I run 235's on 17x8.5's.
Some day I will see if I can fit 28"tx10"w slicks on 15" rims. I'll run those on the street and video it for you. :wave

[dmb882]

Some day I will see if I can fit 28"tx10"w slicks on 15" rims. I'll run those on the street and video it for you. :wave

Hello something giving loose in the rear end/driveshaft department when you dump the clutch :)

[highboostingm3]

Hello something giving loose in the rear end/driveshaft department when you dump the clutch :)
I am still on the waiting list for 1000hp driveshaft and half shafts. If they keep lagging then I might get pissed and change everything in the drivetrain to Supra parts. Toyota built a stock drivetrain nearly bulletproof and BMW didn't. That sucks! :mad

[dmb882]

I am still on the waiting list for 1000hp driveshaft and half shafts. If they keep lagging then I might get pissed and change everything in the drivetrain to Supra parts. Toyota built a stock drivetrain nearly bulletproof and BMW didn't. That sucks! :mad

Ahh I hear ya. I remember when my dad went from a 28in tall slick to a 29.5in slicks he broke the axels in his fully built 8.8 ford" bullitproof" rear end. That was a 9000rpm launch running a blower and 150shot of nos off the line :eyecrazy

heres a pic of a good launch
http://img71.imageshack.us/img71/6625/saleenfz0.jpg

[HyperHoHo]

Some day I will see if I can fit 28"tx10"w slicks on 15" rims. I'll run those on the street and video it for you. :wave

I bet I can make that tire fit for you...just come down to Chicago and I'll make it fit for you :)

[highboostingm3]

Ahh I hear ya. I remember when my dad went from a 28in tall slick to a 29.5in slicks he broke the axels in his fully built 8.8 ford" bullitproof" rear end. That was a 9000rpm launch running a blower and 150shot of nos off the line :eyecrazy

heres a pic of a good launch
That's what I want right there! :buttrock

I bet I can make that tire fit for you...just come down to Chicago and I'll make it fit for you :)
Ah give it up. :D

[techno550]

That's what I want right there! :buttrock

Ah give it up. :D

Might be easier (and possibly faster) to skip the tire mods and do a massive rear bumper reinforcement. It'll take some careful coreography, but if we can have the fully loaded dump truck hit you at the right time going the right speed.... ;)

[highboostingm3]

Might be easier (and possibly faster) to skip the tire mods and do a massive rear bumper reinforcement. It'll take some careful coreography, but if we can have the fully loaded dump truck hit you at the right time going the right speed.... ;)
OMG! :wow What is that I read? A sense of humor from Michael McCoy? YES! :buttrock