Let's Talk Brakes and Geometry

[Simple_Smith]

PROLOGUE (feel free to skip)
Alright everyone, I'll start off with two bits of information: I own an e30 currently in the process of being turboed and its set up for drifting as well as an e36 325i sedan as a daily with no modifications other than stance coilovers. Second bit is last weekend I took a trip down to Robinsville, NC and took a ride on the Dragon with a bunch of crazy Canadians. Now I'm hooked on grip.

I want to build a monster that i can do just about everything with. Living in chicago, there aren't a whole lot of canyons to carve or big wicked roads to cruise, so most of my friends drift and that's a big passion of mine, but after our trip down to the dragon that will certainly become an annual event from now on, I want to move my car to more of a multi-purpose vehicle.

I may have gone a bit too drift ways in the area of suspension geomety.. e46 control arms, tie rod spacers, 10k/12k coils, Z3 rack non-powered, m3 offset cabs, 22mm rear sway and no front sway, along with all of condor's solid bushings.

I'm sure anyone that tracks is just thinking, "wow this idiot ruined his handling" And you're absolutely right. It drives like shit on the street now, but when drifting, it flicks right over and feels perfect to me..

SO.. My main questions/concerns:

1. e46 control arms, can they be made to handle well on the streets, or is it a lost cause?

2. Turbo e30 ~300whp, what brakes to go with? I have 97+ e36m3 knuckles as well as 318ti knuckles sitting on a shelf at work.. or should i just go with stock rotors and race pads, or rx7 calipers with corrado rotors?

3. What for the rear setup now?

4. e32 master cylinder opinions?

I'm just at kind of a stand still right now trying to figure out how crazy to go. Realistically, RX7 front setup with race pads and cooling ducts and possibly e32 master should be more than enough, but i'd like to get some different opinions

Thanks for reading my jibberish ramblings..

[TobyB]

1- measure your front camber. If you can't get it below -3 or so, yeah, that's not gonna
be so hot for street use.

2- go 5 lug and E36M3 rotors. The stock rotor is a bit small for hard track use, as is the stock pad. By 'knuckle' you mean spindle, right? Race pads are only good for racing,
where you get real heat in them and keep them hot. Big street pads work well cool,
and with big rotors you get to keep them cool even when you're tracking them.

3- tii hubs and make those M3 rotors fit.

4- only if the math on the brakes wants it. There are 4 or 5 different E30 options already...

5- I don't remember the translation into lbs/in for springs, but soften to taste...
...and unhook the rear sway for 'normal' use, and try to get that to work,
then hook it up and see how it does drifty.

Carefully.

one butthead's opinions,
t

[Simple_Smith]

Thanks for the response. From what I was reading the 318 spindles (knuckles, whatever term you prefer) have different final offset compared to the m3 knuckles. I should be able to get my camber down to a decent amount on the fronts if I max out my coils positive.. I'm still up in the air if I want to go 5 lug or not, I haven't had any issues with brake fade, so I don't want to get too crazy if I don't have to. As far as swaybar setups go, I have a 24mm IE front sway I've been debating about setting up with end link disconnects to switch over easily from drift to street. Lot of stuff flying around in my head so thanks again for helping me bounce ideas around

[jalopi]

1. e46 control arms are complete garbage, put your e30 control arms back on

2. use your OE brakes + hawk pads. the only real reason you'd need to get a BBK is if you were doing some serious track driving (no, hooning on the street does not count, you will never see the same kind of brake temps) or if you did a v8 swap and needed to compensate for the loss of your brake booster. if you must have bigger brakes, get something from massive. rx7 brakes will give you roughly 20% more braking power for $400. massive's sport kit gives you about 74% for $1300. this translates to the massive kit having approximately 20% more value than the rx7 kit -and- you don't have to have your new rotors machined each time you replace em

3. leave your rear setup alone. add a front sway bar. fixed & done.

4. the old myth of master cylinder "upgrades" just refuses to fucking die. there is no such thing as a master cylinder upgrade, only a properly selected master cylinder. bigger masters (shorter brake pedal travel before the brakes "grab") push more fluid and will apply force to the brake pads sooner than a smaller master cylinder (longer brake pedal travel before the brakes "grab"). however, the bigger master cylinder will apply significantly less force to the caliper pistons than a smaller master cylinder. this isn't my opinion, it's the basics of pascal's law. the people "upgrading" to 25mm or whatever master cylinders are literally decreasing their maximum braking torque in exchange for a more satisfying pedal feel. this isn't to say that you should get the smallest bore master cylinder that you can find, because it won't push as much fluid and you could end up only applying force to your brake pads right before your pedal hits the floor. for instance, if you put rx7 brakes on your car, your front axle would literally lose 400ft/lbs of braking torque with the e32 master vs the e30 master. no bueno

[djjerme]

..actually, for all technical sense, a brake master cylinder upgrade is going to setup that uses a balance bar so you can adjust bias between two master cylinder (i.e. Tilton style dual setup), but 97% of the people driving E30's will never need this. Hell, half the people racing PRO3 cars with brake bias adjusters for the rear, don't actually need them..

I agree with upgrading your pads and just using stock rotors. You already stated you aren't feeling fade. Heat is a race pads friend, so you want it to get hot quick, and then release that heat just as quick after releasing the pad, so make sure your cooling is adequate.

If you decide to go 5-lug in front, just save yourself some headache and swap in the rear setup from an E36 318TI. Same diff, same control arms..blah, blah, blah, same, same EXCEPT 5 lug..

I don't have experience with drifting, but here is what I gather from your first post:

This car will see commuter/hooning duty around Chicago primarily, and drift action "sometimes." Correct me if I am wrong on this.

With that in mind, focus on make the car fun and SAFE to drive around town. You can have a lot of fun on the track with a car that is still safe on the streets and ain't going to put you in to a street pole when a little rain comes down. Yes, I am sounding preachy, but unless you are ONLY going to use it on the track, you want to retain a lot of the street-ability of the car.

Toby can attest, I do drive my full race car to the track. It's not fun. But for me it's necessary because my wife won't allow me to have a trailer. (don't ask.)

Also, keep your car civilized for now, and find someone with years experience drifting. Then toss them the keys to see what your car can do some weekend, chances are, the car is better than your skill. Spend time getting your skill better rather than worrying about the car dynamics at this point. You don't want to be clouding your learning curve with wondering if you should upgrade the brakes or change your steering angle..

Catch my drift?

[Simple_Smith]

Jalopi I do see your point with the e46 arms, i had to notch my control arms to clear at full lock. However I do really like how my car feels with the e46 arms while drifting. which is the reason I'd like to TRY to keep them and hopefully just be able to make changes to the camber as well as a front swaybar with disconnects for drifting.

Thank you for clearing up my confusion about master cylinders. This is why i love r3v

I do catch your drift (nice pun btw) my e30 is mostly for tracking but it does see some street duty and gets driven to the track so must be at least somewhat streetable.

OE brakes + Hawk pads seems to be my best reasonable match for my driving needs right now without going crazy overboard with no real need to.

[jalopi]

just when you upgrade your lock, make sure you ditch the e46 arms. the clearance issues will be 10x worse with any sort of angle kit

also, if you're putting down 300 wheel, you don't need to disconnect your front sway bar. that's a trick people with no power do so they can break the rear wheels loose easier. more power + same amount of grip you had with previous power levels = same drifting speed/coolness as your previous setup

[agent]

This thread may be of some help:

http://www.r3vlimited.com/board/showthread.php?t=350705

Also,

I took a trip down to Robinsville, NC and took a ride on the Dragon with a bunch of crazy Canadians. Now I'm hooked on grip.

...after our trip down to the dragon that will certainly become an annual event from now on...

It's already a bi-annual event every Spring and Fall:

Search for "Brodeo" in the Southeast regional forum.

[IronFreak]

I don't know if this has been addressed but get yourself some akg or SLR adjustable Lcabs. it'll allow you to correct the wonky caster the e46 arms give.

[jalopi]

he's got m3 cabs

but yeah OP, one other reason to ditch your e46 arms. e30 arms will give you more caster, which is better for... well, pretty much all driving situations. there's a good reason why BMW gave the m3's offset cabs

[Simple_Smith]

Jalopi, I had the front sway out for the stock HP level, I'll probably get back into messing with swaybar setups once i get the turbo up and running (just need charge pipes and a downpipe fab'd up)

Agent, I went down there to a car meet in Kentucky; Import Alliance and then cruised down to the Dragon with the Canadians we met in Kentucky

IronFreak, (i feel like i should know your actual name by now, i see that cage pic all the time) I'm running condor offset bushings for the caster, do the treehouse CABs adjust closer to the frame rail than the condors will get? or do they need to be adjusted in the other direction for correcting the caster numbers?

[jalopi]

nope, the only thing different about treehouse cabs is you get more exhaust clearance with em.

offset cabs restore your caster to near-OE specs after installing e46 arms... i wouldn't be surprised if spinning the cabs 180* would give you negative caster

[Simple_Smith]

Which might be nice for the 3" downpipe...

[jalopi]

with any bmw slant 6 you're fine 99% of the time, it's the v8 swaps that have problems with exhaust clearance there

[whiltebeitel]

I'd also recommend hooking up the front sway bar. as long as your camber is in a reasonable range, the next major thing to look at is roll stiffness distribution, and you're adjusting that with the sway bars. With the nose heaviness of a lightweight turbo E30 and the power to the rear, you'll definitely find benefit to increasing the front end stiffness relative to the rear.