Hydraulic roller lifters to solid flat tappets?

[tirod]

Cam profiles are ground with enough ramp up no lifter has issues with the slack. Pushrods against the rocker arm don't either.

Pick a cam for it's profile and intent, non hydraulic have some rev advantages because of the lighter tappet weight. Rollers are limited in the rpm ceiling because of it, but make up with being able to accelerate better in the initial ramp up, where a flat tappet may be slightly restricted to prevent the edge digging in. Conversely, roller tappets may have to endure more side loading.

As for zinc, read the spec, even the latest grade SN oil has some, and the API does still test with flat tappet motors because they are still in service. Nissan and Hyundai even dropped their roller lifters for a nitrided flat tappet. API has to rate the oil for flat tappet use because makers haven't quit using them.

It's all part of the zinc mythology on the net, which is vastly uninformed. Just read the spec and you will know more than 95% of the posters worldwide. Zinc was reduced - not eliminated.

[xb-60]

Thanks gentlemen. I'm convinced. Solid rollers.
Cheers,
Glen

[xb-60]

....if there's any difference in "music" level and "quality" between solid flat-tapper lifters and solid roller lifters? A subjective observation, I know, but it's an important consideration.
Cheers,
Glen

[DAVID GAGNARD]

Can't say about solid flat tappet lifters,but on my solid roller lifter engine in my race car with open exahust,I can certainly hear the "music" from the upper valve trane and it is properly adjusted!!!!!!

David

[patrickt]

Originally Posted by xb-60

....if there's any difference in "music" level and "quality" between solid flat-tapper lifters and solid roller lifters? A subjective observation, I know, but it's an important consideration.
Cheers,
Glen

They sound pretty much the same... on an FE, at least.