Yes, they run them toward the top of the plunger travel to limit how far the lifters can pump up. Really any lifter can be run like that. But dont over do it, because it will limit how far the lifter can adjust for normal valvetrain wear, and the plunger would eventually break the clip. Like I said, 3/4 to 1 turn seems to be the magic amount, and some guys directly measure it.

I've heard of Chevy guys only going 1/4 turn though (although their valvetrain is different)... crazy Chevy guys!

 

From memory of 17 years ago, the only difference in the anti-pumpup lifters I used was a groove cut into the seat for the disc check-valve. This would allow oil to get past much faster.

Every once in a while, I'd startup my 390, and it would rap-rap on a few lifters. But that was only after a few months of sitting. It wouldn't do that every day.

They DID make more noise at idle though. But I have/had double valve springs that were like 200lbs or more range for on-seat pressure. My machinst said to make it bullet proof because I had a Triumph TR7 at the time that I loved to take to 7500RPMs

As I remember, the anti-pumpup lifters were also rated for a much higher valve spring pressure than stock lifters. The stockers were at risk for failing under that much pressure. But I'm not sure on that one.

I would suspect, with the bleed-down being FASTER than a regular lifter, that the internal spring would be HEAVIER to try to counteract the bleed-down.

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Anti-pumpup lifters (as I remember) were intended to keep them from pumping up if you got valve float and then slamming the valve into the piston.

I still have all 16 lifters in my 390 ... if I didn't plan on doing something with it, I'd take a lifter apart and take pics... maybe

 

I need to make a correction on how lifters work. The oil comes in the side, and the plunger is in two parts. That way they only need one check valve.

 

Kurt, how's the low end torque and fuel economy for the 343941 crane cam? How's the 343941 cam for towing?

 

Low end torque is great; You'd think you're driving a stocker. Fuel economy is also good. One trip on the highway I got 17mpg.

Crane also lists the cam for towing, so it'd probably be good there too.

Good all-around cam. Here's what Crane has to say about it:
"GOOD IDLE, DAILY USAGE AND OFF ROAD, TOWING, PERFORMANCE AND FUEL EFFICIENCY, 2600-3000 CRUISE RPM, 8.75 TO 10.75 COMPRESSION RATIO ADVISED. BASIC RPM 2000-5000"

 

The 941 is about the same cam as I had in my 390 - Wolverine Blue Racer, 292/292adv, 230/230@.050", .554/.554" lift. Not exactly, but somewhat close

Advanced 4 degrees, it pulled the 5500lbs '74 highboy around like it was nothing. 2 tons in the bed, still pulled like nothing. Didn't even need 1st (435NP) to move 4000lbs in the bed from a dead stop, and no more than 1500RPMs. w/33" tires and 4.10 gears.

Idle was quite lopey...

Compression was in the 10.5-11 range.

Got 15MPG on a 400 mile trip.

 

Your cam looks a bit more wild than the 941.

941 specs:
Adv. duration: 272/284
.050" duration: 216/228
Lift: .533"/.563"

Idle isn't real lopey, but that depends in a huge way on the amount of initial timing advance. If you set it to the 6-8 degrees they came with stock, then yeah, it'll lope. If you give it what it wants, it'll idle like a stocker. Smooth as glass. There is a technique that works quite well, but I guess it's not PC on this board.

 

PC for whom? No censorship or anything else going on here... post away!

Yeah, it was basically the upper limit for hydraulics...

My only point being even lopey sticks can get great low-end with a 390 stroke...

 

PC for the "purists" who think it should only be set up the way Ford did it.

If I posted it I can guarantee at least 2 members here would jump all over me for it, and may even leave bad rep. So if anyone really wants to hear how to make it idle smooth with a big cam send me a PM.

 

OH NO! Not the big bad "inverted vacuum advance" ?

AHHHGG!!!!!!!

 

What are your thoughts on this Cam?
Edelbrock Performer-Plus Camshaft
Ford FE 352-428
Duration Advertised 272° Intake/282° Exhaust
Duration @ .050'' 194° Intake/204° Exhaust
Lift @ Valve .460'' Intake/.480'' Exhaust
Lift @ Cam .265'' Intake/.280'' Exhaust
Lobe Separation Angle 110°
Intake Centerline 105°
Intake Timing @ .050" Open 8° ATDC
Close 22° ABDC
Exhaust Timing @ .050" Open 37° BBDC
Close 13° BTDC

 

Crap. Compare the duration figures to the 343941 I mentioned above.

 

Almost the same specs as a worn out CJ cam.
270/290, 194/204 @ .050, .481/.490, 46* lap.

 

If you were buying this cam would you include lifters and new springs from Crane also?

 

SurvivThis is a good cam too.

Yes, go with Crane everything (cam, lifter, springs, retainers, etc..) if you this route, that what I did.

Remember more lift more wear.

JMO, I like to keep the lift at above the 0.500 mark and below the 0.560 mark.

I running the Crane 343902 cam/ lifter setup.