A hydraulic roller FE turning 7500 rpm....

[Whodeeny]

Originally Posted by blykins

High rpm FE's have never been a problem. High rpm hydraulic roller FE's have been the bottleneck.

Lots of my customers want a little more rpms without having to run a flat tappet cam or the risk of a solid roller. Now we have options.

I took it to 7500 simply because I wanted to prove my rocker arm design. It went there very easily with only 200 lbs seat pressure and 500 lbs open.

We turn 8500-9000 rpms with <400 lbs seat pressure and 1200 lbs open pressure on my BBF pulling truck engines.....with almost 2.5" valves. The right cam lobe makes all the difference.

What are the risks of a solid roller?

[blykins]

Originally Posted by Whodeeny

What are the risks of a solid roller?

The lifters have needle bearings or bushings in them. Solid cams have lash, which means that the lifter is not always in contact with the cam lobe. Couple that with much higher spring pressures than normal (usually around 600-700 lbs) and you have a lifter that is constantly being beat up. The lifters have a short life span and if you don't keep up with it, you can end up with scattered parts inside your engine and a ruined camshaft.

[Whodeeny]

Originally Posted by blykins

The lifters have needle bearings or bushings in them. Solid cams have lash, which means that the lifter is not always in contact with the cam lobe. Couple that with much higher spring pressures than normal (usually around 600-700 lbs) and you have a lifter that is constantly being beat up. The lifters have a short life span and if you don't keep up with it, you can end up with scattered parts inside your engine and a ruined camshaft.

Brent - What would the expected life span (in miles driven) be for mechanical roller cam lifters for an engine driven on the street? Thanks.

[blykins]

Depends on the lifters, but generally anywhere between 3500-10000 miles.

[Whodeeny]

Originally Posted by blykins

Depends on the lifters, but generally anywhere between 3500-10000 miles.

In your opinion who makes the best mechanical roller lifters, the ones that might run 10,000 miles?