Hello and thank you for having me. I recently assembled a 1974 302 non roller block. I installed Edelbrock performer heads with correct springs for a comp cams roller cam 533 lift intake and exhaust. 224 duration intake and exhaust with a 110 LSA. I installed Comp Cams Evolution hyd roller lifters with link bars. Harland Sharp full roller rockers, 1.6 ratio. I have about 40lbs oil pressure when hot. Hardened pushrods. Here’s my problem: I have a lifter noise. Some of the lifters do not stay pumped up, making it very difficult to adjust. I adjusted lifters down 3/4 turns. Did this numerous times but still have noise. ANY help or ideas would be extremely appreciated. Thank you everyone for reading.

 

If your cam uses the Extreme Energy lobes they are inherently noisy/sound like solid lifters.

 

Yes, I can attest to that - both for HFT and roller applications. I had the hydraulic flat-tappet Comp X4262(Extreme '4x4' 262) previously in the 393W stroker in my Crown Vic. noisy. That engine later got upgraded to a XR276, utilizing the factory Ford lifter spider retainer/dogbones/stock roller lifters. It is also a bit noisy. Comp's idea with the 'Extreme' series is to have very fast event ramps that really smack those lifters/valves open quickly, maximizing 'area under the curve' while also maintaining a relatively short duration for better torque and low emissions. It works, but it makes for a noisy valvetrain.

 

All roller motors have a bit of a mechanical sewing machine sound to them that gets more pronounced with more agressive cams. Is that the noise you have or is it a ticking or tapping noise?

 

If you look at the seating velocities it reveals what's going on with those XE profiles. A hydraulic lifter collapses as the valvetrain actuates in the running engine. A hydraulic cam is typically designed with a ramp height of about .006 for this reason and it allows the valvetrain to set down quietly. The amount that the lifters collapse depends on many factors but it generally increases with RPM.

I did a quick comparison between a couple of lobes that I have on file. My DM200 hydraulic flat tappet that was designed for me by Mike Ingram. It runs quietly and it is a design that's about 2 years old, a very quick flat tappet hydraulic that works well and is intended for moderate RPM use. The other is an XE 274 lobe. What this is is a comparison of the calculated seating velocity in inches per second of the valvetrain at 2000rpm using the same rocker ratio on both lobes and if that seating event would happen at various heights in thousandths:

DM200 XE274
2 6.06 1.68
4 7.32 3.78
6 8.33 8
8 9.34 12.22
10 10.42 15.81
12 11.55 18.94

See how the DM200 has a higher velocity at very low lift, under .006 then it is about the same, and then above that the XE profile has a velocity that is much higher. Take these figures and divide by the rocker ratio(1.73 in this case) so .010 is right at .006 cam lift. The XE lobe is about 50% higher velocity. And this is assuming that the lifter only collapses about .006 but what if it collapses a couple of thousandths more in the running engine? Then your seating velocity is even higher. The profile would probably run more quietly if run with a solid lifter set as a tight lash.

 

Sounds like maybe a tapping noise

 

Wow ! Thanks Dave !! So, am I stuck with the noise? I can hear it from across the street.

 

What directs me to the lifters is the immediate bleed down of just SOME of the lifters. I don’t get why the immediate bleed down, or are they pumping up at all.

 

What the XE lobes typically sound like when the engine is running is an engine with moderately noisy solid lifters not a clacking sound. It is certainly possible that you have one or more lifters that are collapsing/not holding any oil. This can happen when something causes the check ball that's in the plunger to not seat. This would be very noisy. What's weird about noises like this is if all of the lifters, pistons etc are making noise it usually doesn't sound too bad. But if there's only one or two making the sound it is very noticeable.