I have the 3000 on the turbo and the 700 on my carbed, stock compression 72. I had to get new 8mm plug wires on the turbo. I had spark arcing everywhere on the old wire set. I called Crane to talk about the 72. He said that unless it is a high cpmpression/performance engine then go with the PS60 and the 700. I have not started the 72 up yet so I guess I'll find out soon!