I am getting a strong strong vibration/shutter when accelarate between 1500- 400 rpm. I recently had new tires put on the front and moved the old to rear 9 (about 60%). The car was alligned about a yera ago. I am thinking either the half shafts/CV joints or motor/tranny mounts. Any thoughts or advise would be appreciated!

 

So this vibration is only related to the engine speed or is it related to the vehicle speed? If it's related to the engine speed, I'd say check your motor mounts. If anything internal is causing it, you'd hear horrible noises from the engine. I've heard people with this issue have spotted destroyed motor mounts on their TSX.

 

are the directional tires?

In my opinion it is normal for hondas/acuras to cup the rear and they take some time to even out on the front, especially if it was a long over due rotation.

The rotation for FWD usually goes like this.