There's a guy in my neighborhood who is the x-pipe king. He actually introduced me to my mechanic and he's going to put the exhaust in my Imperial if the engine is ever done. He has an all-steel '64 Olds 442 that ran a 9.50@xxxxxxx There was an article in Hot Rod about him and his exhaust shop in June '01. http://members.aol.com/xforcefast/hotrod-june2001.htm Pertinent facts: open headers 430 hp@xxxx 384 ft-lbs full dual exhaust 412 hp@xxxx 371 ft-lbs h-crossover 419 hp@xxxx 378 ft-lbs x-pipe: 428 hp@xxxx 391 ft-lbs Plus the crossover pipe generally quiets the exhaust down a little too. The only drawback is that they get in the way if you have to drop the driveshaft or to work on the trans depending on where you place it. Rob _________________________________________________________________ Scope out the new MSN Plus Internet Software — optimizes dial-up to the max! http://join.msn.com/?pgmarket=en-us&page=byoa/plus&ST=1