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Jack, I've been shopping the parts for my engine upgrade and wonder if you can help me with a few questions.
1. I've located the M-6250-A331 cam. Should the lifters also be Ford. They come in OEM replacement (M-6500-B303) or anti pump-up versions (M-6500-B301)which require an adjustable valve train. What is the correct application for me, and what is the function of "anti pump-up" lifters?

2. It does not appear that the Ford Performance catalog list valve springs and retainers for the 351C, 4V heads. If this is the case, I assume aftermarket parts are appropriate. Is it more important to get the springs and retainers from the same company where I will purchase the one-piece stainless steel valves?

3. Ford also produces roller rockers (M-6564-CS51). Catalog says they are for "canted cylinder heads with non-adjustable valve train. Does not require guide plates, hardened push rods, or pedestal machining." I'm guessing this refers to the 4V heads on my car. Any opinion on these? I guess I can have an adjustable valve train if I choose.

4. I've still not been able to locate the Crane conversion kit to which you refer in an earlier post. Can you supply a part number? I'm assuming this part will work with the Ford roller rockers.

5. I've identified the push rods (Ford # M-6565-M342 and the guide plates (M-6566--D302 for 5/16" rod diameter). I'm assuming these will work with the other parts I've identified and with the Crane conversion kit.

Jack, I understand these questions must be tedious for you and I apologize for my lack of experience in this are. Thanks in advance for your help. I've asked you many questions and you've never led me astray before. Thank goodness for that.

Joel
Original Post
Q# 1) - this is the cam I run myself. It's a good street unit and will only cost about 2 mpg of gas mileage while having noticibly more power than stock. Any new hydraulic lifter will work, but.... Isky 'Superlifters' for instance are 0.060" shorter than stock so if you use Boss 351 pushrods (0.050" longer than stock), they balence each other nicely. Fastbleed lifters from Rhodes or Crane make passing smog easier if thats a concern. Do not use a lifter galley oil restrictor if you run fast-bleed lifters- they need more oil than stock, not less..
2)- Any spring set that more-or-less matches stock specs will be fine. The main thing is to not get locomotive-sized racing springs for a mostly-stock engine. Aluminum heads require seat pressures of 140 lbs max but can use higher rated springs at lift.
3)- This is Fords's version of Crane Cams' adapter kit (or it may BE Cranes kit) for an adjustable valvetrain without machining to Boss or HO specs. It will work fine as long as you follow directions perfectly. What sometimes happens is, the rocker hold-down bolts are smaller than 'normal' rocker studs so they need Lock-Tite on utterly clean theeads to hold, which a lot of people don't bother with. Guess what? The bolts unscrew themselves....
4)- I don't have it- you'll have to phone Crane Cams in FL, I guess. The adapter kits work with any lifters including stock ones.
5)- All this stuff will bolt together nicely, but it can pay off to check the geometry of the system before final torquing down. Assemble the valves (at least one intake & exhaust on each head) with one very light spring each -maybe from a hardware store; Crane sells a 'check-set' cheaply to make checking easier. Bolt a head on with the cam & two lifters; no plugs or any other components needed, and slowly rotate the crank with a ratchet, in the correct direction. While rotating, very carefully watch the action of the roller on the rocker arm: it should start slightly to the outside of the valve stem centerline, and at peak lift, be slightly to the outside of the stem centerline. I have to climb up on the engine with a strong light to see well enough. If not, your geometry is sub-optimum and you get to play around with little shims under the rocker stands to make it so. If its really bad, you might need shorter or longer pushrods or lifters. Depending on who worked on the heads, ground the valves & surfaced the head(s) etc, each head may be different in what it needs- on some engines, each VALVE is different! This is one reason why pro engine builders spend up to 14 days assembling a blue-printed engine.
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