E92 cage design

awe92s65 · 07-30-2015, 11:22 PM

Hello everyone. So after messing with my rear suspension for a month now and spring rates still arnt what I'm looking for I've decided to it will be easier and safer to do a coilover in the rear. Because of the motion ratio issue with the inboard spring I feel like I'm adding unneeded stress to the subframe. I've contacted gmg about installing a cage and they have been very responsive and easy to work with. The price was also very fair, but I'm not sure about how I feel about the design of the cage. Im also not local to them so thats kind of a pain. I was wondering if anyone has some photos of the m3 gt4 cage. That car utilizes rear coilovers so I wanted to see what the factory designed for it. I also would like to mount the rear subframe directly to it for that magical throttle response and durability. Let me know if anyone has any recommendations/photos. I'm in Seattle and was hoping to get a plan and just have my local welder fab it up but for a perfect cage I'm willing to travel.

Scrippy · 07-31-2015, 12:37 PM

I hope you get what you need. I'm very interested to see the factory design also. Please post pics when you get your beast caged!

surlynkid · 08-01-2015, 08:57 AM

You need to reinforce upper perch for rear coil overs. The stock perch is not designed for that load.

awe92s65 · 08-03-2015, 04:21 PM

Quote:

Originally Posted by surlynkid

You need to reinforce upper perch for rear coil overs. The stock perch is not designed for that load.

Yep, that's why i'm looking for cage designs. i was hoping someone had photos of the gt4 trunk interior. the gt4 is based on the factory body and wanted to see what bmw came up with.

awe92s65 · 08-03-2015, 10:09 PM

Found some photos for anyone looking to do the same.

dwennerberg · 08-03-2015, 11:13 PM

I got some cars I can send you pics of. Send me your email

italyix · 08-04-2015, 11:00 AM

I have been looking for a solution to this as well, since my Nitrons R3 can be converted to a rear true coil over, but I wanted a trunk cage only to reinforce the perches. In a side note, VAC Motorsport runs my same setup with a rear coil over without reinforcement, at least that's what they told me over the phone when I bought the suspension. Granted they own a shop, so if anything ever went wrong, they could fix it.

surlynkid · 08-04-2015, 09:01 PM

I would have expected better looking welds if that is a GT4. I would also want nascar door bars on my side in case of a side hit.

awe92s65 · 08-06-2015, 10:58 AM

Quote:

Originally Posted by surlynkid

I would have expected better looking welds if that is a GT4. I would also want nascar door bars on my side in case of a side hit.

I would have thought the welds would be cleaner as well. The photos were pulled from auto sports (the German magazine) site. They cite it as being an actual GT4. I tried contacting one of the members on here with one but never got a response. Anyone else know some with one to confirm. About the nasa style cage. I'm running the oem doors which have impact beams so it's not a huge deal. A lot of guys running the nasa door bars are rocking carbon/fiberglass doors.

EAZ7 · 09-25-2015, 07:08 PM

Well your fabricator be removing your carbon roof for this job?

07-30-2015, 11:22 PM	#1
awe92s65 Enlisted Member 6 Rep 36 Posts Drives: AW E92 M3 Join Date: Apr 2015 Location: Seattle iTrader: (0)	E92 cage design Hello everyone. So after messing with my rear suspension for a month now and spring rates still arnt what I'm looking for I've decided to it will be easier and safer to do a coilover in the rear. Because of the motion ratio issue with the inboard spring I feel like I'm adding unneeded stress to the subframe. I've contacted gmg about installing a cage and they have been very responsive and easy to work with. The price was also very fair, but I'm not sure about how I feel about the design of the cage. Im also not local to them so thats kind of a pain. I was wondering if anyone has some photos of the m3 gt4 cage. That car utilizes rear coilovers so I wanted to see what the factory designed for it. I also would like to mount the rear subframe directly to it for that magical throttle response and durability. Let me know if anyone has any recommendations/photos. I'm in Seattle and was hoping to get a plan and just have my local welder fab it up but for a perfect cage I'm willing to travel.
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07-31-2015, 12:37 PM	#2
Scrippy Lord Scrip 1823 Rep 3,018 Posts Drives: 2011 M3 Coupe Join Date: Jan 2012 Location: LA,Ca iTrader: (0) Garage List [0.00] 2007 BMW 335i [0.00]	I hope you get what you need. I'm very interested to see the factory design also. Please post pics when you get your beast caged! __________________
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08-01-2015, 08:57 AM	#3
surlynkid Major 115 Rep 1,470 Posts Drives: 2013 E92 M3 Join Date: Apr 2012 Location: League City, TX iTrader: (1) Garage List 2010 Porsche GT3 [0.00] 1988 Toyota 4Runner [0.00] 1995 Toyota T-100 4x4 [0.00] 2013 BMW M3 [0.00]	You need to reinforce upper perch for rear coil overs. The stock perch is not designed for that load. __________________ Stoptech 380mm/355mm \| PFC08 / Pagid RS-29 \| Akrapovic EVO - CF tips \| Benvo Tune \| MS UDP \| AA air filter \| MCS 2-way with 700/1000lb springs \| Solid bushings and adjustable links \| RD front swaybar \| Apex EC-7 18x10 square 275/35-18 NT01 \| Turner Race Studs \| GT4 Brake Cooling \| GT4 Power Steering Cooling \| Alekshop Oil Cooler \| Performance Steering Wheel \| \| CF Spoiler \| Varis System 1 Full CF Diffuser \| Extended Paddle Shifters \| Schroth Quick Fit Pro \| Turner Steering Rack Stops \| Vorshlag Camber Plates
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08-03-2015, 10:09 PM	#5
awe92s65 Enlisted Member 6 Rep 36 Posts Drives: AW E92 M3 Join Date: Apr 2015 Location: Seattle iTrader: (0)	Found some photos for anyone looking to do the same. Attached Images Last edited by awe92s65; 08-06-2015 at 10:51 AM..
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08-03-2015, 11:13 PM	#6
dwennerberg Private 0 Rep 71 Posts Drives: e46 m3 Join Date: Mar 2014 Location: OC iTrader: (0)	I got some cars I can send you pics of. Send me your email
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08-04-2015, 11:00 AM	#7
italyix Captain 141 Rep 980 Posts Drives: '08 E90 M3 Join Date: Dec 2011 Location: Bay Area iTrader: (5)	I have been looking for a solution to this as well, since my Nitrons R3 can be converted to a rear true coil over, but I wanted a trunk cage only to reinforce the perches. In a side note, VAC Motorsport runs my same setup with a rear coil over without reinforcement, at least that's what they told me over the phone when I bought the suspension. Granted they own a shop, so if anything ever went wrong, they could fix it. __________________ Mods: too many the list wont fit in the sig page. PM me Tesla Referral code: http://ts.la/juliana77782
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08-04-2015, 09:01 PM	#8
surlynkid Major 115 Rep 1,470 Posts Drives: 2013 E92 M3 Join Date: Apr 2012 Location: League City, TX iTrader: (1) Garage List 2010 Porsche GT3 [0.00] 1988 Toyota 4Runner [0.00] 1995 Toyota T-100 4x4 [0.00] 2013 BMW M3 [0.00]	I would have expected better looking welds if that is a GT4. I would also want nascar door bars on my side in case of a side hit. __________________ Stoptech 380mm/355mm \| PFC08 / Pagid RS-29 \| Akrapovic EVO - CF tips \| Benvo Tune \| MS UDP \| AA air filter \| MCS 2-way with 700/1000lb springs \| Solid bushings and adjustable links \| RD front swaybar \| Apex EC-7 18x10 square 275/35-18 NT01 \| Turner Race Studs \| GT4 Brake Cooling \| GT4 Power Steering Cooling \| Alekshop Oil Cooler \| Performance Steering Wheel \| \| CF Spoiler \| Varis System 1 Full CF Diffuser \| Extended Paddle Shifters \| Schroth Quick Fit Pro \| Turner Steering Rack Stops \| Vorshlag Camber Plates
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09-25-2015, 07:08 PM	#10
EAZ7 New Member 2 Rep 28 Posts Drives: M3 Join Date: Nov 2014 Location: UK iTrader: (0)	Well your fabricator be removing your carbon roof for this job?
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