Hydraulic Roller Lifters-Lifter Bore
 

In regards to hydraulic roller lifters is it required to enlarge the oil passages in the lifter bore or are there dependable roller lifters designed to work without pulling a rotating assembly down to enlarge the oil holes?

For reference this is a combo street/road race application 468. Certainly not a race engine at under 600 hp but a hydraulic roller lifter will be stressed in this form of racing.

Thanks for the help; If the only way the lifter will live is with more oil; I’ll rethink converting to a hydraulic roller.

IMO a nitrated SFT cam is the most reliable street/strip set up for our Pontiacs. Since the Crane hydraulic rollers are NLA we have not found a reliable hydraulic roller lifter for a Pontiac. Just a bunch of expensive sad stories.

Truth!!!!!

Crower Coolface Solid Lifters

Crower Coolface solid lifters feature a small-diameter .024 in. metering port that is precision-machined in the face of the lifter. They will provide longer camshaft and lifter life with no loss of oil pressure. These lifters are designed to eliminate lobe and lifter wear caused by inadequate lubrication at the cam and lifter surface. With today's high-rpm, high rocker arm ratio and high spring pressures, cam and lifter failure is at an all-time high.


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I went this route on my personal build for the same reason. The thought of Chinese needle bearings improperly hardened, flying around in my new engine was keeping me up at night! Saving over a grand between cam and lifters doesn't hurt either. If you only need 500-550 HP, I don't see the need for roller lifters. Use good oil with lots of ZZDP though of course.

x2 for me. If broken in properly, it's hard to beat the old school ruggedness and simplicity of solid flat tappet. That's what my road race project is getting.

Eric

Is this done after the purchase of the cam?

https://www.youtube.com/watch?v=-Ej8cQ2w2xI


Comp Cams 1-111-1 LABOR CHARGE- TO NITRIDE CAMSHAFT


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No, normally the cam is rough ground, Nitrided then finished.

Anyone cryoing cam and lifters?

In regards to solid flat tappet cams and the Crower Coolface solid lifters, are we now at the point where once adjusted properly the solid lifters don't need to be checked for lash on a regular basis? If so, does this require some combination of a lifter brace or shaft style system? I understand the benefits power wise of a SFT cam but want a set and forget setup. Running a hydraulic cam and Rhodes lifters (although a bit noisy) was just that.

Paul Carter will Cryo a camshaft for $145. In the past he has done valvesprings for me.

http://www.cartercryo.com/index.html


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The lifter bore bracing is a roller lifter deal......


'Roller Pressure Angle'

The direction of the applied force lifting a roller lifter is at an angle and not directly along the axis of the lifter. The more aggressive the profile, the greater the pressure angle. Beyond the limit at about 33 degrees, reliability drops dramatically. This side thrust distorts the lifter body and leads to hydraulic collapse. These side loads are not seen with a flat-tappet-style lifter hence the problem is not an issue. The bigger the roller and cam base circle, the less the roller side loading

On a Pontiac application you will often see it touted that a lifter bore brace is typically not necessary until the duration at 0.200" valve lift approaches or is over 200 degrees duration. But even if their roller cams don't follow that guideline many go ahead and install them anyway as insurance

Of interest.... years ago Jim Butler included a list of solid roller cams offered in his catalog (they were Comp Hi-Tech .420 rollers), and with that listing of cams he mentioned specific lobes that he stated "should not be aggressive enough to break lifter bores". Those lobes were from 252 at .050 (169 at .200) thru the top lobe with 282 at .050 (195 at .200).


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You are not going to need a lifter bore brace for any sft cam. I run quality SS roller rockers and a stud girdle with a solid roller cam and my lash does not change. The stud girdle keeps everything tight beyond what just the set screws in the poly locks can do.
IMO if you do the same with a sft cam you will be fine. The Crower SS rockers have a larger bearing than any aluminum RR so they will last longer.
You could buy a shaft system and be golden but expect to pay 1800+$.
"Coolface" lifters ? Well, cars have been running fine without them forever, just need the right oil. Maybe the fancy Crower sft lifters in a road race/endurance deal is of some use. But IMO for a typical nice street engine, no.
The spring pressures for a under 600 HP engine are no big deal. If you want the Coolface lifters its just a few more bucks.
The only problem I have ever had is when I used new lifters on a used cam.

I posted this a few days ago on YB. There are a number of factors which can change pressure angle for the same lobe profile.

Stan

So just how is spring pressure related to HP?

Stan

Not sure about Camshafts and the correct order to Nitride them, Paul, BUT I HAVE HAD OVER 15 CRANKSHAFTS NITRIDED BY MOLDEX AFTER THEY WERE MACHINED. Joe (and Whitey when he was alive) said Nitriding was the last step. I believe them.
Never had a failure of the crank yet.

Tom V.

"Always run enough seat pressure to control the valve action as it returns to the seat. Heavier valves require more seat pressure. Strong, lightweight valves require less seat pressure. When in doubt, run slightly more seat pressure . . . not less."

Crane Cams


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I agree Tom. The Nitrided cams we get from Crower were finished ground and shipped in with their crankshafts to be done. When we order them from Competition Cams and the place that grinds our "house" cams they told me their process is to rough grind, Nitride then finish grind. Also Comp charges for "custom grind" when you Nitride one of their "catalog" cams.

Btw it took some convincing to get Crower to Nitride their cams. They also charged considerably more than the other two places.

Tom, who do you use for this process?

I have been considering either Nitride or Cryo... Just for convo purposes, any benifit to having both processes performed besides cost?

SPEED SAFE, NICK