I've been reseaching camshafts to put in my 400 build. I want to now if anyone can tell me the pros and cons of a split duration cam, where the exhaust duration is longer than intake. I'm more concerned about torque than hp, I just guessed that split was for hp, while the matching held more pressure in the combustion for longer making torque. But like my wife always tell me, I'm prob wrong. Could someone fill me in?
P.s. I'm looking at .050+/-, thanks in advance

 

one of the tricks is getting the most flow out of a flawed port wether it be a restricted intake or exhaust. fords are know for their restricted exhaust ports. so this is one of the ways to tweak the cam on exhaust with some duration or lift to stay open a little longer to compensate for a restricted port. maybe opening changing the exhaust valve timeing to help build cylinder pressure or blow down a cylinder to cheat compression or create compression. valve opens at a certain degree and depending on where it opens depends on how much compression it makes and application with drag racing or towing. their are so many ways to go about this question and not totally answer you question. hope I could help. I use www.mpgheads.com and tim meyer for my ford projects. mpg cuts my heads and scott is very good at what he does, no regrets with scott.

 

used to run a 268 comp cam high energy and it was a great cam. wouldn't run anything bigger for towing mileage in mild application. stay below 268 duration and should be good to go. just a ballpark answer hope I could help.