[bimmer777]

I am not too familiar with the foam strength but I do know if the TMS kit is properly welded in, you will shatter the diff into pieces before the mounts will go. If you have the means, go ahead with the TMS kit.

Alternative would be to beat the sh!t out of you car for the next two weeks so the crack exceeds 2cm and you get a new rear end...and then weld the TMS kit anyway so you will never have to deal with this again!

[IGotId]

Originally Posted by bimmer777

I am not too familiar with the foam strength but I do know if the TMS kit is properly welded in, you will shatter the diff into pieces before the mounts will go. If you have the means, go ahead with the TMS kit.

Alternative would be to beat the sh!t out of you car for the next two weeks so the crack exceeds 2cm and you get a new rear end...and then weld the TMS kit anyway so you will never have to deal with this again!

that's the kind of info i was looking for!

[AzN_m5]

Originally Posted by IGotId

that's the kind of info i was looking for!

Yeah same here...the added foam i was planning might just be overkill.

[playskool1]

Originally Posted by bimmer777

I am not too familiar with the foam strength but I do know if the TMS kit is properly welded in, you will shatter the diff into pieces before the mounts will go. If you have the means, go ahead with the TMS kit.

Alternative would be to beat the sh!t out of you car for the next two weeks so the crack exceeds 2cm and you get a new rear end...and then weld the TMS kit anyway so you will never have to deal with this again!

how would the TMS kit shatter the diff?

[drunk hal]

Originally Posted by playskool1

how would the TMS kit shatter the diff?

he just means that the differential would shred itself before the subframe mounts would rip again

[Mr.G3]

Originally Posted by AzN_m5

Yeah same here...the added foam i was planning might just be overkill.

If you do not have currently any cracks/damage, why wouldn't you just apply the foam, instead of welding the TMS plates- remember the welding will result in rust- since the sections will not be able to be primed in at the welding points (noone will dip your car into prime, as they do during manufacturing).

To my understanding, the foam is supposed to reinforce a non cracked/damaged subframe mount, as a preventative measure, to the extent that you would never need the TMS parts...

[M3Seeto]

Originally Posted by G3_M3_FY04

To my understanding, the foam is supposed to reinforce a non cracked/damaged subframe mount, as a preventative measure, to the extent that you would never need the TMS parts...

Do you have any data to support this ?

Im curious to see how many people had the foam fix from BMW, still beat their car and never experience cracking again.

[Mr.G3]

Originally Posted by M3Seeto

Do you have any data to support this ?

Im curious to see how many people had the foam fix from BMW, still beat their car and never experience cracking again.

The terocore structural foam, FUS-1908,(http://www.rozars.com/PrintProduct.aspx?productId=12109) or equivalent, has been widely used to strengthen frames in race car prep. This method will not work on a damaged mount -even with hairline cracks- as you will need to weld the mounts down the road, it will be a PITA/dangerous (I think welding on foam can create toxic fumes).

That's why I asked him why would he do the welding if he doesnt have any damage as of yet...

I dont have any white paper or reputable scientific report stating it- but I dont think you will ever find any, anyways.

[M3Seeto]

Good explaination and i agree with you.

If you were in my situation, would you still add the TMS kit it ?

Im taking a risk and its irritating me.

I have the foam in place, the crack left as is. I cannot weld the TMS kit on it because of the foam.

However i can epoxy the TMS kit. But what happens if it cracks ? I have to replace the whole floor at my own expense

Like BiMMER777 says, drive the crap oout of it to see if the mounts crack >20mm ? ?

[nrubenstein]

Originally Posted by bimmer777

I am not too familiar with the foam strength but I do know if the TMS kit is properly welded in, you will shatter the diff into pieces before the mounts will go. If you have the means, go ahead with the TMS kit.

Alternative would be to beat the sh!t out of you car for the next two weeks so the crack exceeds 2cm and you get a new rear end...and then weld the TMS kit anyway so you will never have to deal with this again!

Of course the downside of the TMS kit is that it severely compromises the rust proofing of the car. The foam fix is much better from a longevity point of view (especially done as a preventative measure), and it does not prevent you from installing the TMS kit later if you do experience a failure.