Subframe Reinforcement Status Thread

[BlueBimmers]

Planning for this post-COVID-19. Anyone have this done is the greater Wash DC metro area? Fellow enthusiast gave me the name of RRT out of Sterling, VA.

[scubastove]

Planning for this post-COVID-19. Anyone have this done is the greater Wash DC metro area? Fellow enthusiast gave me the name of RRT out of Sterling, VA.

RRT did the subframe reinforcement for my other m3 (currently for sale) with Turner plates, done under previous ownership. It was done in 2015 and has held up so far for ~35k miles

[Nick_P]

I just completed this as well, went with Reddish plates and Turner solid bushings/ mounts, monoball RTABs. After reading from multiple sources about how just the reinforcement plates are not a permanent solution, anyone care to share pros and cons of Vincebar, CMP topside beam kit plus front extension and Mason X-brace? One would be that the Mason bar doesn't extend to the front mount area I guess, any other ideas?

[roverT]

Agreed. Anyone know of any trusted shops/mechanics in Canada (particularly west coast) that has done a CMP subframe reinforcement?

My good friend Josh did mine at his private place. I was probably one of the first, two years ago to get Vincebar and skinz epoxied to the car. We just used welding to fix the cracks in the RACP.




As you can see I had some pretty major problems on both bottom and top sides.

RACP-6018


RACP-6186

But then once we got everything fixed, it was time to install the parts...


RACP-6349


RACP-6376

Once the top parts were installed and Vinceskinz underneath was all epoxied and riveted to the RACP, everything was rust primed and rustproofed and the inside trunk was color matched painted with the plate covering the Vincebar.


RACP-6399


RACP-6408

It's been a couple years now and everything seems fine and I am loving the freedom and peace that I can launch and drift with no guilt.

[wsybert]

New delrin subframe and Rtab bushings are installed. Ready for reassembly. I used seam sealer on all the welds and coated everything with POR 15. Going to do one more coat of POR and start reassembly this weekend.

[Syfon]

I had a thread on M3Forum with a heap of pics etc., but we all know that's gone. Here's a few pics of mine.

[BigDave]

Just did my reinforcement this weekend. Got the underside done yesterday and waiting on new bushings. Once it is back together, I will do the trunck area. This is my second time doing this... first was a 1999 E46 328 I turned into a track car... forgot how my much of a PITA this was.
Mine is a 2003 with 55k. Not a crack or issue when looked it over... now it's good for a long time!

How do you do the trunk area? Are you talking one of those giant bars that takes up half of your trunk space?

[martin.oconnor]

Pulled my subframe at 96k and found no cracks (also examined the interior of the RACP cavities with a boroscope to look for cracks around the mounts). I don't baby the car but it was never tracked and hard launches are not my thing.

Decided to use structural foam on all four mounts (writeups here and here). Nothing fully convinced me that plates were a permanent solution (plenty reports of failures with these) and I have not seen a single report of post foam failure (open to correction there).

[Neil I]

Had the RACP checked by Reddish a few years ago and also had them reinforce it with the structural resin as there were no cracks present. I've recently fitted a brace from PureTech Sweden to add more reinforcement to that area. Also heard of may reports of plates failing. These seem to be only a temporary fix to the cracking issues and just move the problem to the next weakest point in the RACP. Hopefully the brace will provide a permanent fix to the rear mounting points

[Robert's_BMW]

Had the RACP checked by Reddish a few years ago and also had them reinforce it with the structural resin as there were no cracks present. I've recently fitted a brace from PureTech Sweden to add more reinforcement to that area. Also heard of may reports of plates failing. These seem to be only a temporary fix to the cracking issues and just move the problem to the next weakest point in the RACP. Hopefully the brace will provide a permanent fix to the rear mounting points

Are plates and the puretech sweden brace enough? I was thinking of getting this brace but I wasn't sure if this was enough or if I needed to go all the way to a Vincebar kit to resolve the subframe issue. I don't really care about trunk space so a visible brace or hidden VIncebar is fine by me. Any thoughts?

[heinzboehmer]

[QUOTE=Robert's_BMW;n27453]

Had the RACP checked by Reddish a few years ago and also had them reinforce it with the structural resin as there were no cracks present. I've recently fitted a brace from PureTech Sweden to add more reinforcement to that area. Also heard of may reports of plates failing. These seem to be only a temporary fix to the cracking issues and just move the problem to the next weakest point in the RACP. Hopefully the brace will provide a permanent fix to the rear mounting points

Are plates and the puretech sweden brace enough? I was thinking of getting this brace but I wasn't sure if this was enough or if I needed to go all the way to a Vincebar kit to resolve the subframe issue. I don't really care about trunk space so a visible brace or hidden VIncebar is fine by me. Any thoughts?

Doesn't look like the front mounts are addressed from the top, so I would say it's not enough.

[Robert's_BMW]

[QUOTE=heinzboehmer;n27456]

Doesn't look like the front mounts are addressed from the top, so I would say it's not enough.

But you can buy the front gusset cups separate from Vince if I remember correctly. So would the brace and gusset cups be enough?

[heinzboehmer]

But you can buy the front gusset cups separate from Vince if I remember correctly. So would the brace and gusset cups be enough?

Yeah that should be enough. I haven't seen one of those swedish braces in person, but it looks like it's tying into the rear mounts and bracing them against the shock towers, so should be fine.

[AussieE46M3]

Regarding the original post about using epoxy foam, I've had several customs who have had to reinforce their cars with weld in plates and topside reinforcements who had foam injected by BMW back in the day.

The foam adds a bit of anxiety to the job and is highly flammable however, doesn't seem to catch fire unless directly exposed to an ignition source.

I personally would avoid the foam entirely.

[martin.oconnor]

Regarding the original post about using epoxy foam, I've had several customs who have had to reinforce their cars with weld in plates and topside reinforcements who had foam injected by BMW back in the day.

Can you be more precise.

You have personally witnessed post-foam injection subframe failure? With cracks that were larger than the ones that necessitated the injection of foam in the first place? In the same corners where foam was injected? Which corners typically show cracks? Was foam injected into all four corners of these cars or just the left rear as per the BMW TSB?