ZPOST
BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read


Go Back   ZPOST > BMW Z4 Technical Talk > Track / Autocross / Dragstrip / Driving Techniques
  TireRack

SUPPORT ZPOST BY DOING YOUR TIRERACK SHOPPING FROM THIS BANNER, THANKS!
Post Reply
 
Thread Tools Search this Thread
      10-27-2012, 04:58 PM   #1
Kgolf31
Brigadier General
Kgolf31's Avatar
39
Rep
3,349
Posts

 
Drives: 2007 Z4MC, 2012 128i
Join Date: Sep 2008
Location: Ohio

iTrader: (3)

4 Point Harness w/out Harness Bar?

Is there any mounting bolts that we can secure a 4-point harness to for Auto-x? A local was showing me his harness mounting bolt in his GT3 that he discovered and I didn't know if there was anything similar.
__________________
12 128i Coupe - Project STX: TCKline l Active Autowerke l APEX l Vorshlag l Dunlop l Hawk l BMW Performance

Appreciate 0
      12-01-2012, 11:43 PM   #2
mfanatic325
///M-fanatic
mfanatic325's Avatar
Taiwan
51
Rep
3,688
Posts

 
Drives: '07 Z4MC, '04 325Ci
Join Date: Oct 2007
Location: Cupertino, CA.

iTrader: (20)

Garage List
Send a message via AIM to mfanatic325
I don't think there's such a mounting point for the Z4s. Maybe the child safety lock points on the passenger side might suffice, but it'd be kinda risky I think. Better to get an actual bar at the very least, if not a half to a full cage.
__________________
VF570 S/C|TIAL BOV|SetRabCooler|Brembo GT 6/4|TE37s|NT05s|3.91 Gearing|TCK D/A|RPi Induction|SS Race Mufflers/X-pipe|JVT Headers|AS SSK|VibraTechnics Mounts|Sparco Pro2000/6pt.Harness|MS FloorMounts|SE Custom Harness Bar|Tekarbon Angels|M-Tech Pedals|OE Strut Bar|RE RSMs|8000K D2S|CDV DEL|CF Roof Wrap|MB Grills|UUC TrannyMounts/ClutchStop|V1 Mount|P3C Gauge
Appreciate 0
      12-02-2012, 09:50 AM   #3
Beedub
Brigadier General
United Kingdom
54
Rep
4,085
Posts

 
Drives: 2007 Z4 M roadster vt2-500
Join Date: Sep 2007
Location: UK

iTrader: (0)

funny.... i was wondering this same thing.... i saw a 1M at my local event and he fitted some bolt down eyelets to the seat mount points and attached them their... im not sure if this is legal or not.
__________________
Pristine Bi-colour Ti /Bsm...z4m roadster Ess vt2-500....Perfection on wheels.
Appreciate 0
      12-02-2012, 03:16 PM   #4
mfanatic325
///M-fanatic
mfanatic325's Avatar
Taiwan
51
Rep
3,688
Posts

 
Drives: '07 Z4MC, '04 325Ci
Join Date: Oct 2007
Location: Cupertino, CA.

iTrader: (20)

Garage List
Send a message via AIM to mfanatic325
Quote:
Originally Posted by Beedub View Post
funny.... i was wondering this same thing.... i saw a 1M at my local event and he fitted some bolt down eyelets to the seat mount points and attached them their... im not sure if this is legal or not.
If we had back seats, we could potentially use the rear seatbelt receptacles as some form of mounting
__________________
VF570 S/C|TIAL BOV|SetRabCooler|Brembo GT 6/4|TE37s|NT05s|3.91 Gearing|TCK D/A|RPi Induction|SS Race Mufflers/X-pipe|JVT Headers|AS SSK|VibraTechnics Mounts|Sparco Pro2000/6pt.Harness|MS FloorMounts|SE Custom Harness Bar|Tekarbon Angels|M-Tech Pedals|OE Strut Bar|RE RSMs|8000K D2S|CDV DEL|CF Roof Wrap|MB Grills|UUC TrannyMounts/ClutchStop|V1 Mount|P3C Gauge
Appreciate 0
      12-02-2012, 03:17 PM   #5
beta
Lieutenant Colonel
28
Rep
1,655
Posts

 
Drives: 2006 M Roadster
Join Date: Mar 2011
Location: CA

iTrader: (2)

From what I understand you should only run a 4-point if you have a cage.

Otherwise in a roll-over the 4 point will keep you upright into to the collapsing roof/windshield. The hack went into it a bit here.
__________________
Appreciate 0
      12-02-2012, 03:26 PM   #6
Beedub
Brigadier General
United Kingdom
54
Rep
4,085
Posts

 
Drives: 2007 Z4 M roadster vt2-500
Join Date: Sep 2007
Location: UK

iTrader: (0)

Quote:
Originally Posted by mfanatic325 View Post
If we had back seats, we could potentially use the rear seatbelt receptacles as some form of mounting

no no no.... his bolted straight down to the floor, they looped over the tops of the seats and was bolted down to where the runners are bolted to the floor..... like i say, i have no idea if this is sufficient in terms of safety.
__________________
Pristine Bi-colour Ti /Bsm...z4m roadster Ess vt2-500....Perfection on wheels.
Appreciate 0
      12-02-2012, 03:38 PM   #7
Kgolf31
Brigadier General
Kgolf31's Avatar
39
Rep
3,349
Posts

 
Drives: 2007 Z4MC, 2012 128i
Join Date: Sep 2008
Location: Ohio

iTrader: (3)

Quote:
Originally Posted by Beedub View Post
no no no.... his bolted straight down to the floor, they looped over the tops of the seats and was bolted down to where the runners are bolted to the floor..... like i say, i have no idea if this is sufficient in terms of safety.
Yea, that's a no-go.

You need to maintain a certain angle in relation to the seat for the straps behind the seats
__________________
12 128i Coupe - Project STX: TCKline l Active Autowerke l APEX l Vorshlag l Dunlop l Hawk l BMW Performance

Appreciate 0
      12-03-2012, 12:57 AM   #8
mfanatic325
///M-fanatic
mfanatic325's Avatar
Taiwan
51
Rep
3,688
Posts

 
Drives: '07 Z4MC, '04 325Ci
Join Date: Oct 2007
Location: Cupertino, CA.

iTrader: (20)

Garage List
Send a message via AIM to mfanatic325
Quote:
Originally Posted by Kgolf31 View Post
Yea, that's a no-go.

You need to maintain a certain angle in relation to the seat for the straps behind the seats
Yup, the two shoulder straps cannot pull downwards on you.
__________________
VF570 S/C|TIAL BOV|SetRabCooler|Brembo GT 6/4|TE37s|NT05s|3.91 Gearing|TCK D/A|RPi Induction|SS Race Mufflers/X-pipe|JVT Headers|AS SSK|VibraTechnics Mounts|Sparco Pro2000/6pt.Harness|MS FloorMounts|SE Custom Harness Bar|Tekarbon Angels|M-Tech Pedals|OE Strut Bar|RE RSMs|8000K D2S|CDV DEL|CF Roof Wrap|MB Grills|UUC TrannyMounts/ClutchStop|V1 Mount|P3C Gauge
Appreciate 0
      12-03-2012, 04:36 AM   #9
007MCoupe
Major
007MCoupe's Avatar
19
Rep
1,462
Posts

 
Drives: on the wrong side of the road
Join Date: Jun 2010
Location: Livin' life

iTrader: (4)

Garage List
2007 Z4 M Coupe  [0.00]
how much does a harness bar typically cost? a half cage?
__________________
GoMiniGo///VB3///75mm wheel studs///Stubby///Aero bumper///GC front ARB///Pin pulled & Turner Camber Shims///Superflex FCAB///Powerflex RTAB///RE shock mounts///ECS 2-pc front rotors///Akebono pads///CSL headers///DKF catless Section 1///AKG Engine & Trans Mounts///SS brake lines///RPI scoop
Appreciate 0
      12-03-2012, 11:21 AM   #10
Kgolf31
Brigadier General
Kgolf31's Avatar
39
Rep
3,349
Posts

 
Drives: 2007 Z4MC, 2012 128i
Join Date: Sep 2008
Location: Ohio

iTrader: (3)

The main reason I asked this, is that I need to maintain class rules for SCCA Solo.
__________________
12 128i Coupe - Project STX: TCKline l Active Autowerke l APEX l Vorshlag l Dunlop l Hawk l BMW Performance

Appreciate 0
      12-03-2012, 01:13 PM   #11
mfanatic325
///M-fanatic
mfanatic325's Avatar
Taiwan
51
Rep
3,688
Posts

 
Drives: '07 Z4MC, '04 325Ci
Join Date: Oct 2007
Location: Cupertino, CA.

iTrader: (20)

Garage List
Send a message via AIM to mfanatic325
Quote:
Originally Posted by 007MCoupe View Post
how much does a harness bar typically cost? a half cage?
For a custom harness bar only, you're looking at upwards of $350 for materials and labor. If you want a half cage, that'll probably bump up to $500. And for full cage, depending on bolt in or weld in, I wouldn't be surprised if it went all the way up to $1,500 or more; as there's lots of labor involved.
__________________
VF570 S/C|TIAL BOV|SetRabCooler|Brembo GT 6/4|TE37s|NT05s|3.91 Gearing|TCK D/A|RPi Induction|SS Race Mufflers/X-pipe|JVT Headers|AS SSK|VibraTechnics Mounts|Sparco Pro2000/6pt.Harness|MS FloorMounts|SE Custom Harness Bar|Tekarbon Angels|M-Tech Pedals|OE Strut Bar|RE RSMs|8000K D2S|CDV DEL|CF Roof Wrap|MB Grills|UUC TrannyMounts/ClutchStop|V1 Mount|P3C Gauge
Appreciate 0
      12-04-2012, 04:26 AM   #12
SmartBastard
Stupid as shit
SmartBastard's Avatar
Austria
8
Rep
364
Posts

 
Drives: '08 M Coupe
Join Date: Jan 2011
Location: Vienna, Austria

iTrader: (0)

Hmm I newer looked into this so spare me some slack if this is a retarded idea, but couldn't you just get a rear strut bar and mount the harness there? Or is the rear strut bar not strong enough for that?

Can't find any Z4M rear strut bar, but what I mean is smth like this:
Appreciate 0
      12-04-2012, 05:01 AM   #13
mfanatic325
///M-fanatic
mfanatic325's Avatar
Taiwan
51
Rep
3,688
Posts

 
Drives: '07 Z4MC, '04 325Ci
Join Date: Oct 2007
Location: Cupertino, CA.

iTrader: (20)

Garage List
Send a message via AIM to mfanatic325
I suppose that might actually suffice as a shoulder strap bar. However, one would need to strip out everything behind the seats in order to get at the bar. Also, there's still the issue of the angle of the shoulder straps to where it's actually wrapped around/mounted. But interesting thought process there. I've never thought of using a rear strut bar for such a purpose
__________________
VF570 S/C|TIAL BOV|SetRabCooler|Brembo GT 6/4|TE37s|NT05s|3.91 Gearing|TCK D/A|RPi Induction|SS Race Mufflers/X-pipe|JVT Headers|AS SSK|VibraTechnics Mounts|Sparco Pro2000/6pt.Harness|MS FloorMounts|SE Custom Harness Bar|Tekarbon Angels|M-Tech Pedals|OE Strut Bar|RE RSMs|8000K D2S|CDV DEL|CF Roof Wrap|MB Grills|UUC TrannyMounts/ClutchStop|V1 Mount|P3C Gauge
Appreciate 0
      12-04-2012, 11:54 AM   #14
AUTOX08MC
Enlisted Member
AUTOX08MC's Avatar
0
Rep
37
Posts

 
Drives: 08 Z4m Coupe
Join Date: May 2011
Location: Indianapolis

iTrader: (0)

I believe a full roll cage, or partial roll cage/bar is permitted in any class of SCCA autocross.
__________________
08 Z4 MC, Arctic White, GC Suspension 650/800, GC Swaybars (med/soft), Remus Cans, SS Lines, BMW Strut Brace, TC Cline RTAB, RPI Scoop, Stock Wheels w/ Dunlop Star Specs 245/275, Autocross Wheels: Apex 18x9.5 18x10 all w/285/30 A6 Hoosiers, Fabspeed Headers, Evolve Tune, Aluminum Adjustable Rear Camber Arms
Appreciate 0
      12-04-2012, 01:15 PM   #15
Kgolf31
Brigadier General
Kgolf31's Avatar
39
Rep
3,349
Posts

 
Drives: 2007 Z4MC, 2012 128i
Join Date: Sep 2008
Location: Ohio

iTrader: (3)

Quote:
Originally Posted by AUTOX08MC View Post
I believe a full roll cage, or partial roll cage/bar is permitted in any class of SCCA autocross.
I will have to check, but I'm almost positive not.

You increase the stiffness of the chassis.
__________________
12 128i Coupe - Project STX: TCKline l Active Autowerke l APEX l Vorshlag l Dunlop l Hawk l BMW Performance

Appreciate 0
      12-04-2012, 01:49 PM   #16
AUTOX08MC
Enlisted Member
AUTOX08MC's Avatar
0
Rep
37
Posts

 
Drives: 08 Z4m Coupe
Join Date: May 2011
Location: Indianapolis

iTrader: (0)

From the rulebook:
3.3.2 Roll Bars
Roll bars or roll cages are strongly recommended in all cars.
__________________
08 Z4 MC, Arctic White, GC Suspension 650/800, GC Swaybars (med/soft), Remus Cans, SS Lines, BMW Strut Brace, TC Cline RTAB, RPI Scoop, Stock Wheels w/ Dunlop Star Specs 245/275, Autocross Wheels: Apex 18x9.5 18x10 all w/285/30 A6 Hoosiers, Fabspeed Headers, Evolve Tune, Aluminum Adjustable Rear Camber Arms
Appreciate 0
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
Forum Jump


All times are GMT -5. The time now is 03:02 PM.




zpost
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
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