How much HP/torque can the SST transmission in an Evo X MR take? I have heard that you shouldn't go over 350 torque on the MR, but on You Tube I seen a 500HP MR and they couldn't break the transmission.

 

Keep in mind that torque and HP are two different things, HP is a function of torque. Its possible to make 500whp and keep torque at a maximum of 350.

HP = Torque x RPM / 5252.

 

I've been making 385 ft lbs for several thousand miles now, plenty of folks making more than that w/the SST. Overall it seems to be a fairly durable unit. I do change the fluid and filter at regular intervals though. Car has 36K miles and SST seems to still be as solid as the day the car was purchased. (by the way ... NEVER launched but 1st gear limiter removed). Some hold up, some don't...i've been fortunate so far.

 

http://www.youtube.com/watch?v=QzbzaoFhp9U

The MR transmission is much stronger than originally feared.

 

I believe Gertag has listed there's a limitation somewhere in the 330-350 ft-lb neighborhood. I would not consider adding mods that push it over 350 without installing better clutch packs and cooling / deeper pan.