Engine Rocking??

[ScottyCBoy@aol.com]

Got a problem, at max boost (1.8 Bar) and good traction the engine in my 5ktq
moves back far enough for the exhaust pipe to hit the "mystery bar" underneath
the driver's and passenger's foot well.  I just replaced the rear trans
mounts, the engine mounts are in good shape, the muffler hangers are all good
and exhaust is stock.. 
What could be the problem???  This didn't happen until I replaced the mounts,
they were stock units...  I noticed the the front mount (under the IC) isn't
adjustable, unlike the 4kq's, is there anyway to modify it as to limit engine
rock??  Any help will be greatly appreciated..

Thanks,
Scott