ratsmoker-im shure you have seen a car that has oh 200,00 mile son it right? well the oil pressure is not high at this time. take off the pan only replace the mains and rods and run it agian i gaurentee that as soon as u start it the oil pressure will be very high and after it warms up the oil pressure is the same as it was b4 u changed the rods and mains. i have done this before

 

adilts,

If your motor is that old and tired (200k), by all means completly rebuild it, you've got oil sneakin past everything in that mill at that point. When someone has a fairly fresh engine still in good shape though, many, many do change just the cam. All of the hi-perf shops I have dealt with over the years do this type of cam change on a regular basis, but only on a decent engine, not something that has excessive clearances throughout due to being completly wore out, why waste your time at that point tryin to pull some HP out of something shot is like p*****g in the wind. A cam change is one heck of alot cheaper on a healthy engine than yanking a motor and rebuilding it, quicker too!! Pride???Whats up with that one???? No lack of pride here!!!

 

Ya I agree with94f150-408. As long as shes not a high miler and has good oil pressure changing the cam should be no probs.You'll need to remove the intake to get at your lifters and and remove the water pump and timing cover to get at the cam. Cams and lifters need to be replaced as a set. You cannot use old lifters with a new cam or viseversa. Only on a roller camshaft can you use your old lifters as they have no wear pattern. Hope this helps

 

I have never even thought about replacing the cam bearings during a cam install.

Like said above if the cam bearings need to be replaced it is time to rebuild the entire motor.

 

As it is right now, my 351 is making pretty decent power. I think it is around 240-250 HP and about 340 torque. The cam that I've been thinking of getting is the Comp 4x4 cam. the ones that are made for low end power. Does anybody have any idea about how much a cam like that would increase my power. the lift on the one i'm looking at is .456 i believe. I was hoping for upper 300s for torque. does that sound about right. thanks

 

If your running a basicly stock engine with the stock Ford heads and valve size than take a look at the camshafts that Ford offers for the 351. they offer about 7 different grinds, the milder grinds are an upgrade from stock but work well in stock engines. One thing that you must consider with cam selection is your compression ratio. More radical camshafts bleed off compretion as a result of valve overlap( both intake and exhaust valves both being open at the same time for a vew degrees of rotation. Some aftermarket cams actually run 14 degrees of overlap on mild grinds just to get a radical sound at an idol. Not what you want in a truck engine, this only makes the vehicle more cold blooded and less off idol torque.
I think that it's preatty hard to beat the quality of the factory engine parts. What new Ford engine won't outlast a rebuilt? My 89 Ranger has the original clutch. I will replace it with one from the Ford parts counter!

 

Hey buddy i ran an engine on my desktop dyno that i think is basically what you are running. I got the camspecs off of compcams website. I ran a 351 with duals and headers,dual plane intake, 600cfm carb .456lift and a 268 duration and a 110 lobe seperation. Here are the results:

Flywheel Hp- 265@5000rpm peak
Flywheel Torque-352@ 2000 rpm peak

Looks alright to me if your looking for low end torque. Hope this helps.

 

Fisherman, you didn't say what your axel ratio or what tranny your running. I'll bet your F250 has 4.11 axel ratio if so you don't need an extreem low rpm cam.

 

I have a c6 and as far as I know, there are 3.55s in the back. The reason I am thinking of getting one of the low end power cams, is because I dont care about going fast or doing burnouts, I just want low end torque. The kind of stuff I need to pull people out of holes, or puling stumps and other stuff like that. the truck is not bad on power now with the edelbrock intake and carb, plus the headers but i think a cam would realy let it make some good power down low.