I just had my 355 Gen 1 motor freshened rings, cam, bearings. I was going to do the 20 min 2K rpm break in with open headers.
1) I've had a couple people say no way because if there is something wrong with the motor you won't be able to hear it.
2) With brand new ceramic coat Doug's headers I was thinking they may not discolor as bad with less back-pressure.
Opinions please.
Hooking the exhaust up could cause a week set-back in the schedule.