|
Remember as well that using a wider LSA and not advancing the ICL back will give you a very late IVC which kills DCR. DCR = TQ. Also, the more OL you have the larger the cam will act extending it's usable rpm band. So if I use small lobes, keep it advanced, maximize OL for it's size the more DCR you keep and the wider power band you can get. It will also have more driving tq and more power under the curve. In the end, you have to look at the weight of the vehicle, gearing, converter size for A8 or trans gearing for M6's, flow characteristics of the head with an IM attached, exhaust with headers, intended use of the vehicle and a bunch of other stuff to get it right.
The LT head has much larger runners than the LS3 but has smaller valves. Now valve angle and runner length effect the efficiency of the runner size. So don't get all caught up on cross section and runner size. But what you need to realize is that if you don't flow the head with the IM/TB attached and an exhaust tube then you don't really know the flow percentages to spec a cam with. Just flowing the head makes you think you need a wide duration split. But once you put the IM/EX on there the numbers change greatly. This requires a much tighter duration split. You also have to take the entire lift curve of the intake and exhaust into consideration. C/D comes into this equation also. But I digress.
|