This should probably be in the newbies section but I figured there's more traffic here, so..
I put my car up on the hoist for a look around and found this big red brace that seems to tie the diff to the back of the transmission. It's cracked through at the back (a little hard to see). Is this a factory brace that's been painted a funky colour? or is it an aftermarket thing? I did an image search for "fd3s diff brace" but didn't come up with anything that looked like it. I guess I will weld it up where it sits. Trying not to think about what else might have been damaged by whatever was strong enough to crack this brace!

 

This is the power plant frame. In general a red power plant frame means it could potentially be a reinforced mazdaspeed unit or someone painted it red

 

thanks for that. I just googled "mazdaspeed power plant frame" and confirmed that I've got the little placard up there too, so it's a genuine unit... didn't stop it cracking though haha!

 

AFAIK, the genuine difference/benefit between those and the standard PPF was never really established.

 

That looks like fatigue cracking. Crack could have been started/caused by wheel hop - notorious for causing differential and other damage on FD's. Search for threads on wheel hop.

 

Thickness of the stampings, best verified by weighing the PPF

 

Weight is the enemy of Mazdaspeed.

Their other option (besides thickness) would have been a more expensive material specification.

Like chromoly steel versus mild steel when building a rollcage.

 

the Mazdaspeed catalog says its "Hot Rolled Steel Plate"

 

You can have that welded or find a used one in the forum's marketplace.

 

already zapped it up thanks everyone

 

Time to get hold of an FSM. PPF is pretty central to the FD

 

from the catalog,

 

I offer $25 just for the plaque.