Roller Lifters

[Ziegelsteinfaust]

Yesterday I got my low mileage LT1 350 to swap into my truck to get rid of my pre-ignition issues. After I swap in a new cam to lower dynamic compression.

The 383 LT1 in my truck has the AFR hydra-rev kit. For those of you who don't know what it is. It's a package that puts part of the spring pressure on the lifter body. So the plunger does not start to collapse when you hit 5500 rpm roughly. Among a few other things it can do. Rather or not they matter.

Now we have short travel lifters which supposedly with the right set up can go as high as 8000rpm. Definitely higher then the 6500 powerband my new cam will run.

Is there any benefit to the hydra-rev set up vs reduced travel lifters?

Or was it's whole point before we had reduced travel lifters.

[AussieinNC]

The ultra rev kit design has been around since the late 1950's,,,,

It has 2 main functions:

To keep the lifter in contact with the cam to prevent the lifter from floating off the nose of the cam at high rpm's....

and

In the event of a push rod failure, the lifter does not get pounded out of its bore by the cam action.

In most V8 engine designs if a lifter comes out of its bore the engine will lose oil pressure and fail....I have seen it many times.

You can run them on the street without any issues, but would usually get better bang for your buck by getting the right springs and rockers for your engines cam....

If you intend to run 8000 rpm you need a whole lot more than an ultra rev kit....as the old saying goes....

"Speed costs money, how fast do you want to go?"