E36 Turbo "Special" REAR Alignment Specs

[Butters Stoch]

Going in for a alignment in the morning. Looking to see if any of you guys have any documented specs for rear alignment.

I don't do alignments @ my shop, but I have a buddy that will set it up however I wish.

Here is what im looking for.......
Im not after a road course, or high speed twisty driving specs.
I would like it to handle decent, but I don't go barreling down roads with tight corners for the most part. Im also not looking for setting it up to square up the rear tires on the hit for drag racing.

Id like if someone has found a happy medium. The majority of the driving I do is highway pulls, I like taking the on/off ramps at a decent speed. I also enjoy hitting the black top.
Maybe somewhere in between a stock and a drag setup. Id like to keep the tire wear at a minimal, and get a little more contact patch for the straight line.

Here is my rear setup from the tailshaft back
DSS driveshaft
4 clutch 3.23 lsd
AKG red diff bushing
M3 axles
Powerflex race subframe bushing
M3 trailing arms
UUC poly RTABS
M3 balljoints
UUC lower adjustable arms
Koni yellow shocks
UUC rear bar
Adjustable rear springs. (Don't know the spring rates)
They are raceland spring. Had H&R oe sports but needed to remove to clear the 26inch DRs.

Running 9.5 rear wheels and have plans for future flares
Current size 255/35/18

Any input would be cool.

[runsideways2]

Camber it so much that you look like the deloaren from back to the future they got up to 88mph in a short distance.
I think the extra camber will get you better 60 foot times.

[MikeE36]

For best drag traction, you're going to be somewhere near 0* camber, but this will rotate really easily on the street if you like to trail brake or come a little hot into a corner. I'd shoot for somewhere in the -1.0 range to get you a little more corner bite so it doesn't catch you off guard, but still a pretty good contact patch for the straight line.

For drifting I run 0* rear camber, 0.70* total toe in (0.35 each side)

For road racing, -2.5-3.0 rear camber and closer to 0.30* total toe in (0.15 each side). I would split the difference for your uses and go -1.0 camber and just mild toe in for high speed stability.

Also I would find your rear spring rate if you can. Changing that will make a huge difference on forward bite as well.

Mike

[crazyyardie]

mikes specs are exact. when i want to save my tyre wear i add + camber and for cornering i add -camber. drag 0 . is it that u want the exact spec from the machine that it should be

[Butters Stoch]

For best drag traction, you're going to be somewhere near 0* camber, but this will rotate really easily on the street if you like to trail brake or come a little hot into a corner. I'd shoot for somewhere in the -1.0 range to get you a little more corner bite so it doesn't catch you off guard, but still a pretty good contact patch for the straight line.

For drifting I run 0* rear camber, 0.70* total toe in (0.35 each side)

For road racing, -2.5-3.0 rear camber and closer to 0.30* total toe in (0.15 each side). I would split the difference for your uses and go -1.0 camber and just mild toe in for high speed stability.

Also I would find your rear spring rate if you can. Changing that will make a huge difference on forward bite as well.

Mike

Exactly what im looking for, was hoping you would pop in this thread.
As far as "hot in a corner", I don't generally take corners at high speeds.

So how does -0.5 camber and toe in .15 ea sound ?

[MikeE36]

Exactly what im looking for, was hoping you would pop in this thread.
As far as "hot in a corner", I don't generally take corners at high speeds.

So how does -0.5 camber and toe in .15 ea sound ?

That'll work great. If you don't corner carve much or aren't ever really at the limit of the tires laterally, -0.5 should be great for you. That seems like a good compromise.

Mike

[Keith1054]

Exactly what im looking for, was hoping you would pop in this thread.
As far as "hot in a corner", I don't generally take corners at high speeds.

So how does -0.5 camber and toe in .15 ea sound ?

Be VERY specific about units when you take it in. Degree, inch and mm are all commonly used and easily confused with each other.

Very similar to what Mike suggested above, I currently run -1 degree of camber per side, and 0.20 degree total toe. In inches units thats 0.1" total toe in (0.05" per side). For a slightly higher priority on cornering vs. straight line grip keeping in mind really good tire wear.

[Jkpgt96]

Subbed. Great thread OP!!

[Butters Stoch]

Thanks guys, I truly appreciate it.
This is very informative and over the years, I haven't really seen a thread dedicated to rear suspension setup.

You can have the best parts, but if not properly dialed in, then its a big waste.
Pretty much fully built and just replaced the steering rack. So now is the time to dial it all in and make use of it.

Now that I got the chassis, suspension and steering built up. I can now feel better about going for some more power. I didn't want to be one of those guys that had 800wheel on a stock chassis.
I can safely say (still knocking on wood tho) I have a good 75-100 passes this year without a tow home. Im still working on putting it all together aka launching techniques, and collecting advise from the knowledgeable ones.

In the end, id like to have a reliable 10second street car.
The CES car is a great inspiration.

I will let you guys know how the alignment comes out, hopefully post a pic of the sheet.

Please, guys like me seeking advise for alignment specs, feel free to use this thread. Having Mike respond so quickly was a gift.
Maybe he will do the same for you.

[e36ALPINE]

For best drag traction, you're going to be somewhere near 0* camber, but this will rotate really easily on the street if you like to trail brake or come a little hot into a corner. I'd shoot for somewhere in the -1.0 range to get you a little more corner bite so it doesn't catch you off guard, but still a pretty good contact patch for the straight line.

For drifting I run 0* rear camber, 0.70* total toe in (0.35 each side)

For road racing, -2.5-3.0 rear camber and closer to 0.30* total toe in (0.15 each side). I would split the difference for your uses and go -1.0 camber and just mild toe in for high speed stability.

Also I would find your rear spring rate if you can. Changing that will make a huge difference on forward bite as well.

Mike

Great advice. Mike-are you doing your own alignments? I'm thinking about trying to make my own "alignment setup" so that I can do it myself at home with my lift. Any advice?

[daze450]

http://forums.bimmerforums.com/forum...or-your-E36-M3

Not posting that to be a dick, but if we are talking alignment I figured others with less experience (like myself) could read that also, theres some good basic info in there concerning alignment! just figured if we are compiling some alignment info it was a useful thread

Maybe some will agree with the specs talked about in there and some wont im not trying to say that thread is the correct specs but just some more info for people like me trying to learn a thing or two :P

[Butters Stoch]

http://forums.bimmerforums.com/forum...or-your-E36-M3

Not posting that to be a dick, but if we are talking alignment I figured others with less experience (like myself) could read that also, theres some good info in there concerning alignment! just figured if we are compiling some alignment info it was a useful thread!

Alot of guys with 500+hp/tq need more contact patch and custom alignments for traction. Probably wont find these specs in the E36 section.

[jjjjjjj]

What Mike said is spot on about the tail-happy part... On stock 325i power i went from -3 down to -1 camber and notice that the rear wants to come around with a lot less effort and I'm sure that will be amplified greatly with close to 500whp so I'd be slightly concerned about -.05 and taking corners like you are driving a BMW.

I'm currently at -1 and .020 toe on each side and it's been a great compromise all around (for stock power) with daily driving and a little bit of drifting.


What are your front specs?

[wazzu70]

Doing an alignment yourself is not all that hard. Toe plates, camber gauges, and string are good enough for most people in the pits. The hardest part of toe alignment is making sure its even side to side which is where the string helps out. There are also fancier methods of setting toe, but I figure most here are budget minded.

If you aren't constantly adjusting your setup its probably easier/cheaper to just have the job done on a proper alignment rack.

[Butters Stoch]

Doing an alignment yourself is not all that hard. Toe plates, camber gauges, and string are good enough for most people in the pits. The hardest part of toe alignment is making sure its even side to side which is where the string helps out. There are also fancier methods of setting toe, but I figure most here are budget minded.

If you aren't constantly adjusting your setup its probably easier/cheaper to just have the job done on a proper alignment rack.

I have an old Hunter rack. But stopped doing alignments years ago.
Still use the rack, but as a spare lift. Alignments only run me $39 @ my buddy's shop. But I do know some old timers that string the car off. With todays technology, alignments are very precise and wouldn't do any string alignments unless it was a beater. Pay the $60 or whatever most shops charge IMO

[Inicent Child]

+1 to what mike suggested. I am running around 1 degree negative camber and .15 toe in on each side at the rear. Car saw a huge improvement you can power out while boosting out of corners in 3rd and it was very balanced. For a street car I would recommend front toe as close to 0 maybe just a slight bit toe in to aid stability when braking and about -1.8-2 camber, rear usually has 1 degree less camber and .15 toe in. Tire wear is minimal that way.

[beeasy]

Very good information is this thread on a very much over looked subject in my opinion.

What works well for me in the rear which I find to be balanced with similar driving style.

.5 degree camber
.5 degree total toe in

[ZimDoc]

It seems you found the spec's you want but down the road if you want to try more or less of something here's a short run down of the basics.

More toe in the rear will make the car stable at high speeds but will wear tires faster and will have poor turn in.
Less toe or zero toe in the rear can make the car feel like its "floating" at high speeds and can wiggle under hard braking and turning

Camber due to our suspension design can even go to zero degrees because under compression we gain a little bit of camber.

Toe is what wears tires, camber moves the contact patch that the toe will effect the tires the most. I run -3.5 to -4 degree's of camber in the front of my track car with zero toe and have no problems with excessive tire wear when driving to and from events.

I'd rock what Mike or Beeasy said.

[Butters Stoch]

Well, went in for alignment. Here is the funny part. ....
Over the winter I pulled the rear of the car completely out. Right down to the sheetmetal. I coated the underside with POR-15, replaced all bushings, sandblasted everything and also coated with POR-15. I eyeballed the rear as I assembled.
Here is where I was @ .
LR camber .6*
LR toe .13
RR camber .5*
RR toe .15

[BadBoostedBmwM3]

Well, went in for alignment. Here is the funny part. .... Over the winter I pulled the rear of the car completely out. Right down to the sheetmetal. I coated the underside with POR-15, replaced all bushings, sandblasted everything and also coated with POR-15. I eyeballed the rear as I assembled. Here is where I was @ . LR camber .6* LR toe .13 RR camber .5* RR toe .15

Umm, your eyes are pretty good. Those specs should have proven, by now, to have upmost traction from your tires.

[Butters Stoch]

Umm, your eyes are pretty good. Those specs should have proven, by now, to have upmost traction from your tires.

I got no wear, but I don't run expensive tires on the street. So I blame the tires for traction loss. I only lose traction in 3rd if its below 60*. But @ the strip I use pretty good tires. I still wanted it checked. I knew the rear was close, I pulled the car out in april and the rear never wondered. But after changing the steering rack, I figured now is the time to get some advise for specs.

[m3mods]

Sub'd

[Robocop]

I tell people my car is faster when it's hot.
The hotter the day the faster my car is.

Why? Traction
I went from ultra cambered out lowered e30 to 1* camber
didn't make a ton of difference compared to driving at night vs day.
e30s get crazy camber when lowered btw.

[e36ALPINE]

So I realized before I went to the track that my wheel to fender measurements go as follows.
Front wheel center to Fender 13"
Back wheel center to fender 12"
Compared to stock ratio (from what I could find which wasn't much and I'm talking ratio not actual measurements) It seems like my rear should come up about an inch. Does this sound right? Can you guys take some measurements. I'm just trying to decide if raising the rear will help my 60' times or not. Also will raising an inch or so screw up my rear alignment enought to be bad?

[e36ALPINE]

So I just strung my car (string and jackstands) I would say that it is as close to zero toe front and rear as you can get. I literally couldn't really measure how far off the one rear tire is (slightly toed in maybe a 1/16th at most?) without my caliper. I was really hoping this string meathod would be my easy answer to being able to change my suspension setup to try and get my 1/4 mile times down without spending $80 everytime I tweak something. Or I can just tweak away and know if it's as close as it is now it's probably fine.