BMW 1 Series Coupe Forum / 1 Series Convertible Forum (1M / tii / 135i / 128i / Coupe / Cabrio / Hatchback) (BMW E82 E88 128i 130i 135i)
 





 

Post Reply
 
Thread Tools Search this Thread
      05-26-2017, 04:26 PM   #1
Luftmeister
Office Linebacker
United_States
33
Rep
133
Posts

Drives: 135i
Join Date: Aug 2014
Location: United States

iTrader: (0)

Improved but modest upgrades.

I do a few autocross events per year, and a couple of HPDE events.

I like what was in this thread:

http://www.1addicts.com/forums/showthread.php?t=819476


I'll add I have 245 RE-071R on DForce 9" 41mm wheels. 5mm spacer because rubber was contacting strut under hard cornering. Square setup.

It rubs. A little. Fender. Over hard bumps.

I like that build because it's modest and looks like it would save a lot of drivability.

I got a set of the Dinan Camber plates. (Swapped for a set of brake pads from my M3 which I couldn't use.) I like the idea of these because I can always go to a much better camber plate.

We won't discuss the fact that under-steer is on the window sticker as a FIO.

So they should give me at least SOME neg camber and help alleviate the rub.

I'd like to do it stepped in this order. Thoughts and advice? Thanks!

-Code out the nanny
-Dinan front camber plates
-Bilstein B12 suspension and M3 rear subframe bushings.
-E93 M3 sway bars front and rear
-Wavetrac 3.08 LSD

Thanks,
Appreciate 0
      05-26-2017, 05:53 PM   #2
1and1
Loves me some MHD!
1and1's Avatar
United_States
1846
Rep
1,709
Posts

Drives: faster than he should...
Join Date: Jul 2016
Location: Tally, FL

iTrader: (2)

Garage List
'09 135i  [10.00]
Replying to
1) get subscribed & follow your progress
2) compliment & endorse your "under-steer is on the window sticker as a FIO" comment


Have you thought about using the M3 control arms as another method of addressing understeer?
__________________
1and1
135i - E82.N54 2009 BSM - MHD / xHP / DCI, PR CP & 7.5" Race IC / N55 mid & Borla
. . WL RSFI, Koni, Eibach & Dinan CP's, M3 CA's / EBC Red's & Firehawk 500's
X1 - E84.N20 2013 MGM - JB4 - The Wife's, now with new turbo & ewg
Appreciate 0
      05-26-2017, 06:48 PM   #3
bNks334
Major
bNks334's Avatar
427
Rep
957
Posts

Drives: '11 135i (N55)
Join Date: May 2014
Location: New York

iTrader: (1)

Nothing on that list will help with understeer.

What mods people recommend will depend entirely on what class you want to stay in for autocross..
Appreciate 0
      05-30-2017, 08:47 AM   #4
Luftmeister
Office Linebacker
United_States
33
Rep
133
Posts

Drives: 135i
Join Date: Aug 2014
Location: United States

iTrader: (0)

Quote:
Originally Posted by bNks334 View Post
Nothing on that list will help with understeer.

What mods people recommend will depend entirely on what class you want to stay in for autocross..
Well, in your experience and opinion what would?

Better rubber already has, and every car I've owned getting better negative camber, lowering and suspension bits has as well.

Not concerned so much about Autox as just improving over all handling for HPDE. Thanks!
Appreciate 0
      05-30-2017, 09:41 AM   #5
lowside67
First Lieutenant
219
Rep
361
Posts

Drives: 2011 BMW 128i
Join Date: Apr 2015
Location: Vancouver, Canada

iTrader: (0)

Quote:
Originally Posted by bNks334 View Post
Nothing on that list will help with understeer.
The camber plates definitely will help with understeer. Getting some camber under the car (ideally 3+ degrees) is critical, and while the Dinan plates won't provide that much, it's a step in the right direction.

However, I would also say that if this is actually going to be a tracked car or a somewhat serious attempt to improve the car, you should skip the Dinan plates and go to real camber plates. The extra adjustability and maximum camber attainable is worthwhile.

Mark
__________________
Appreciate 1
      05-30-2017, 12:29 PM   #6
bbnks2
Colonel
1207
Rep
2,025
Posts

Drives: 135i N55
Join Date: Jan 2017
Location: NY

iTrader: (0)

Quote:
Originally Posted by Luftmeister View Post
Well, in your experience and opinion what would?

Better rubber already has, and every car I've owned getting better negative camber, lowering and suspension bits has as well.

Not concerned so much about Autox as just improving over all handling for HPDE. Thanks!
Sorry I was referring to your "to do" list. A square setup is for sure #1. Camber helps a bit, but not as much as people are claiming unless you actually have the car setup to make use of it. Adjustable camber plates are great for this reason, you can adjust your alignment over time as your mods, overall grip, and driving ability progress.

The other mods aren't going to help under-steer, specifically. Most people I've seen argue an lsd will promote under-steer a bit since rear traction will be improved. That is until you hit the limit of course where power over-steer will quickly take over when both rear wheels break traction at the same time.

I am actually starting to think the e-diff plays a big role in promoting under-steer. Application of the rear brakes mid turn seems to cause the car to either run wider or shift weight causing the front tires to loose traction before the rear. Once my track pads are hot (PFC-08), the car feel like it bucks through a turn if I turn too sharply spinning the rear tires a bit. I can't wait to get a mechanical LSD, but I may code out the e-diff and run an open diff in the mean time. Plenty of fast autocross cars run open diffs.

Mclaren founded the concept of usign the brakes to steer the car in F1, and from an interview I found stated: "You need a very progressive brake material that has a flat friction/temperature curve, so that it doesn’t grab. Some other teams used material with higher peak friction but more temperature sensitivity. A driver would have more trouble regulating the brake-steer on that material.” which seems to be exactly the type of problem that seems to be upsetting the cars balance mid-turn... a square tire setup, greater later g's than BMW programmed for, different brake bias, different pad material, it all effects e-diffs functionality along with how DSC is programed if you run with that on too (I don't).

Last edited by bbnks2; 05-30-2017 at 12:37 PM..
Appreciate 1
      06-03-2017, 06:01 PM   #7
jvb6806
Private First Class
United_States
30
Rep
160
Posts

Drives: 2010 128i
Join Date: Jul 2011
Location: Chicago

iTrader: (0)

Garage List
2010 BMW 128i  [10.00]
I also went the... we'll say frugal... route of B12's and camber plates but I honestly wish I had just saved up bought the right stuff the 1st time. I autoXed and PDXed the b12's with over -3* camber but the car didn't start to rotate with that setup until I had a 20mm rear bar and subframe inserts to induce oversteer. I was also running an e93 M3 front bar that didn't help the cause.

The B12 kit was fun on the street but severely lacking on track. The dampers were great for what they are but the springs were just way to soft for what I was trying to do.

If you are running SCCA be careful with the street touring rules in regards to camber plates and swapping the lower control arms. It is a one or the other thing. I am running the TCKline camber plates with offset delrin bushings in my lower control arms to get to -3.2*. I was able to get close to -3.5* on the b12's because you can shove the strut top under the hole in body. That doesn't work with top adjusters.

If I had to do it all over again I would have started my build with a call to TC Kline... shortly followed by a call to diffsonline.
__________________
Appreciate 1
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 10:47 PM.




1addicts
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST