Long story short, the new engine has some grunt compared to the old 451. Went to the local track Saturday to put a couple of hits on it and it ran pretty good for not changing the fuel set up from the last motor. First pass went good except with worrying about everything new in the motor, I forgot to turn the air shifter on and the 1-2 shift was late. Then I pulled the 2-3 shift early. With 26* timing it ran good and went 10.16. Next pass with 30* timing in it left extremely smooth and tripped the 60 ft clock with the rear tires with 1.466. Well the ride wasn't over there. As it continued to reach for the sky it was just starting to lay over in the top of first gear it clicked second and went the rest of the way up. By this time it was starting to cruise pretty good and I hear a VERY distinct scrapping sound of the rear valance on the track. The thing had started to drift towards the guard rail and I had to attempt pedaling it down. Well it didn't come down easy, but it wasn't on the guard rail. About a foot and a half between the car and rail. New diaper and my Charlie's pan are now wall hangers. Hind sight being 20/20, I should have tightened the front shocks up all the way and took some more of the travel away up front. Back to the shop. Beep