Anyone got these ? I can find the specs for mustangs easily enough but I am curious as to what the 5.0 in the Ex has stock. I want to know this to see what difference 1.7 roller rockers would make to everything.
Thanks !
Thanks !
I was looking at this same question the other day. This is the general consensus from posts in various forums - nothing official, so take it for what it's worth:
Explorer 5.0
0.422 / 0.448 lift (1.6 rockers)
256 / 266 advertised duration
Mustang H.O.
0.444 / 0.444 lift (1.6 rockers)
276 / 266 advertised duration
Mustang Cobra 93
0.479 / 0.479 lift (factory 1.7 rockers)
270 / 270 advertised duration
Forum lore suggests that a good budget combo is the HO cam with 1.7's.
I was talking to FRPP tech awhile back and they said that 1.7's should be OK on a stock Ex engine. Using the above numbers, The HO cam with 1.7's should have slightly less max valve lift than the Explorer exhaust with 1.7's.Also, wouldn't a HO with 1.7's run into valve spring binding on a stock GT40P head ?
I was checking out your thread and thought I would jump in. Just remember more lift does not always mean more hp. I was reading a pony rag a while back and they tested the theory of rr's vs stamped steel in several different formats on a 306 with P heads and a small cam I think it was around .512 at stock lift. Anyways turned out the motor made more power with 1.6's on the intake and 1.7's on the exhaust than it did with 1.6 or 1.7 all the way around. Which does seem to go with the fact that even though the P heads are one of the best stock iron heads from Ford they still fall into the same relm as all Ford heads in that the exhaust port is always the weak link.
No do not use the stock stamped steel I've read too many times were even though they are rated at 1.6 most often they fall short of that mark. I been a long time pony guy before makeing the switch to an X and have found that even aftermarket stamped steel are better than the stock ones. So when you do decided to change out the rockers go with roller on intake and exhaust weather your testing the 1.6-1.7 combo or lineing them up all the way around.