- Joined
- Dec 3, 2010
- Messages
- 644
I have rebuilt my 1970 fastback and installed a PW3 cam The bike has been back on the road for about a month and I've covered about 250 miles. She starts and runs well and the exhaust note is crisp and raspy. Whilst I have only briefly taken the revs up to 5000 as part of my breaking in process, the acceleration is not that impressive. Lots of noise but not much go. I was expecting a marked improvement over the pre strip-down standard. (that was with a broken top ring on each piston and 0.012" wear on the bores and the original std cam) I was meticulous in setting the cam timing to achieve 0.145" lift at TDC as per the instruction sheet and that involved retarding the cam by 5 (crankshaft) degrees over the standard timing marks. With the std timing marks I had 0.165" lift at TDC i.e. cam is opening too early = advanced.
The $50,000 question is, should I advance the cam to standard timing mark settings to try and improve the performance? there is no kick in the pants as you open it up and that seems to echo what one of the UK NOC members says. There must be a good few members with PW3 cams fitted. I would appreciate any feedback on your experiences. The carbs are Jim Schmidt flatslides and are as fitted before the rebuild and were good then, Ignition is Boyer and set to 31degrees BTDC at 5000.
The $50,000 question is, should I advance the cam to standard timing mark settings to try and improve the performance? there is no kick in the pants as you open it up and that seems to echo what one of the UK NOC members says. There must be a good few members with PW3 cams fitted. I would appreciate any feedback on your experiences. The carbs are Jim Schmidt flatslides and are as fitted before the rebuild and were good then, Ignition is Boyer and set to 31degrees BTDC at 5000.