[lust4speed]

Couple of thoughts. For the dragstrip, I would prefer the turnbuckle because of its ability to prevent engine movement - the less stuff squirming around, the better. On the street, I would go with the chain (or preferably cable) and maintain about a 1/4" slack to prevent transmission of engine vibration to the frame, to the steering shaft, and finally to the steering wheel. This will allow the engine mount to do its job of isolating vibration, and also put a specific limit on engine lift. Only time you want the chain tight is under acceleration. If I felt any vibration at idle or normal cruise, then I would add just a bit more slack.