which cam shaft

[FE Specialties]

Roller cams seem to be frought with much controversy and misguided rumors. All late model V8s are running hyd roller cams today. Why? They are far more reliable and make more torque and horsepower with the same specs as a flat tappet cam. Thats why the majors have all gone to them.
All roller cams, whether they are hydraulic or solid, are splash oiled. There is no orifice on a hyd roller that oils the roller, they are splash oiled too. The variable that determines reliabillity is spring pressure. Depending on how radical the grind, determines how much spring pressure you will need to run.
I highly recommend roller cams in all applications. All you have to do is grind the cam to your application, and the reliabillity will follow.
In a FE street Cobra, I would grind something on the lines of .605 gross lift, 282 advertised duration, 246 .050 duration on a 110 lob separation. You would need about 140 closed pressure, and 390 open pressure to run this cam up to 6800 rpm. Peak HP would be about 6200, so you really would be shifting at about 6300 so you would never get to redline.
This cam will make about 35 more HP and 55 more ft/lbs of torque than the same flat tappet cam, and with this low of spring pressure, you are not going to destroy the rollers. The reason for the rumor of roller cams lifters going bad is that guys were putting full race rollers in their street cars with over .700 inch lift with #600 of open pressure. This wont last over a couple of thousand miles if that. But a street roller with a lot less open pressure will last as long if not longer than a flat tappet cam due to the friction reduction from the roller lifter.
It's time to get modern in the Cobra world. The 30 year old way of building motors is over., Step up to the new tecnology that's available today. To many people build motors for Cobras like we were still in the 70's.
Tom