I installed a 3.27 rear end and recently re-did the cylinder head. That is, I replaced the head because I had stripped the spark plug thread in one cylinder and found, after I had removed the head, that it had been machined below the minimum thickness. Now the car runs much better. When I really want to out-accelerate another vehicle, I put the transmission selector in "2". The acceleration is quite satisfactory, but gloves, sunglasses and everything loose falls down.