| Message |
4*, you take out the advance and add additional retard, until it stops making more power. The reason I suggested he get adjustable intakes was his lack of VTC, so he could "mimic" at least part of the benefits of the VTCs. I forgot how much advance the VTCs create when engaged. What I found interesting is, in a couple hour discussion with Clark and Mike Smith at JWT (who have been designing and producing cams for a variety of racing organizations for some time now), it isn't the retarding of the exhaust cams that gives our cars so much better performance. But it's the overlap that it produces that helps spool the turbos and make more top end power. It's opposite of what was once thought to be the case (which is why JWT designed their exhaust cams with 4* of advance built in). As an aside, SZ says they see less benefit retarding stock cams, than high performance ones (even taking the 4* advance out of the equation). However, I had a stock cammed Z tuned by them, and Greg retarded one side 8*, and the other 4*, until I stopped picking up area under the curve. Engines just vary from one to another and need to have the cams adjusted on a dyno, to ensure max benefit.
|
 |
