xdc351 said:
In an article I was reading recently from the US they swapped a flat-tappet cam to a nearly identical spec roller cam and shaved 0.3 of their quater mile time and noted much better low-mid range power.
I had to register just so I could add something to this from my personal experiance. That sounds like a bogus article, unless they had a really lousey flat tappet cam.
Here's why I think this; A couple of years back, I sheared the pin in the front of the cam on my solid roller camshaft. Since I was in the midst of a points battle, we fixed it, but put a solid flat tappet cam in instead. The specs were similar. The solid roller was 264/272 duration @ .050, .650/.650 lift, 108 lsa and used .026/.028 lash. The solid flat tappet was 266/277 duration @ .050, .625/.623 lift, 107 lsa, and used .022/.024 lash. With the solid roller the car ran low 6.40's in the 1/8 in the heat of the summer (the last full pass with the roller it ran 6.43.) When I put the solid flat tappet in, I expected it to slow down a bit. First pass with the flat tappet cam, it ran 6.43. The 60' time was the same as was the mph.