Stiffening the convertible chassis

[Pac1373]

^Why^ if you want coupe stiffness, the easiest and least expensive way to do it is to buy a Coupe. Deleting the ragtop, and filling the back with a half of a cage will negate this being anything other than a tool for a very specific range of weather/driving conditions.


P.S. thread is back from the dead...

[SwiftE30]

So here is my car with H&R sport kit, springs and shocks, before i dropped in an s52 (still working on the turbo build though) I am really unhappy with the ride height and stance. The back sags way too low. i rode in my friends 325i coupe with m52 swap tht had GC coilovers with 500 front and 625 rear. My plan is to go with 550 front and 675 rear.



I know that an s52 turbo vert is going to flex like none other, soo My question for all of you is, has anyone thought of eliminating the ragtop and welding in some triangle brackets and connect the rear shock mounts to stiffen up the rear? if it were possible i would prefer to do this and eliminate the ragtop all together.

Also, i was thinking that welding in a half cage without the main loop going above seatbelt harness, or somewhere around there, so you cant see it from a side view, might be a good idea. This would really stiffen up the back for sure.

Any input is greatly appreciated! Thanks.

[Alpina]

I have a S38B38 and the subframe is lowered by 20mm

i hope it will fit

[CorvallisBMW]

To avoid the inherent issues mentioned with the homemade "butt-brace" why dont you put inside the car under the rear seat attached to the head of the rear subframe bolt?

Not possible, the whole rear unibody section of the convertible is very different than the coupes/sedans. There is no access to the subframe from inside the car on a convertible.

[3bvert]

To avoid the inherent issues mentioned with the homemade "butt-brace" why dont you put inside the car under the rear seat attached to the head of the rear subframe bolt?

I wqas wondering that too

[bimmer_E30]

it's easy, if you want to stiffen a vert e30, just sell it lol.

[redmist]

To avoid the inherent issues mentioned with the homemade "butt-brace" why dont you put inside the car under the rear seat attached to the head of the rear subframe bolt?

[ejnight]

Trying to install the crossbrace right now and the holes on the brace don't line up to the ones on my vert.

The bolt holes are smaller than the diameter of the bolts but I think that is due to the powercoating taking up space.

edit: It seems as the PS rack holes are closer together on a vert than it is on a hardtop. We drilled out the holes a but in order to bolt the crossbrace on.

I think I will open the holes a tad. I may have the tolerance a little tight.

[MC Hammered]

Trying to install the crossbrace right now and the holes on the brace don't line up to the ones on my vert.

The bolt holes are smaller than the diameter of the bolts but I think that is due to the powercoating taking up space.

edit: It seems as the PS rack holes are closer together on a vert than it is on a hardtop. We drilled out the holes a but in order to bolt the crossbrace on.

[ejnight]

Can you describe where the spacers go?

Car -> skidplate -> spacers -> crossbrace?

Or is it obvious when I try to bolt them together?

first install the skid plate. if done remove the PS rack bolts remove the CA bolts. Hold the brace in place slide spacers between skid plate and brace install new longer bolts though the cross brace, spacer and skid plate. then the CA bolts. Leave it all loose until all bolts are started they tighten and you are done.

Can you give a price for the skid plate & your x brace? I took it that the pic of your X brace was $249 - add the skid plate to it & the package price is ? What would shipping be to 92630 (So Ca).

Thanks - they look very nice

$399 + $35 for shipping of both units.

[bimmer_E30]

will get one asap.

[MC Hammered]

skidplate and brace combo is $399 + shipping

[cactusjacks1]

Can you give a price for the skid plate & your x brace? I took it that the pic of your X brace was $249 - add the skid plate to it & the package price is ? What would shipping be to 92630 (So Ca).

Thanks - they look very nice

[MC Hammered]

Can you describe where the spacers go?

Car -> skidplate -> spacers -> crossbrace?

Or is it obvious when I try to bolt them together?

[ejnight]

Actually I do have your skid plate and that is why I'm happy your made the cross brace.

So how does that change the install?

you will only use two spacers.