Fred's 2375 Rebuild Thread Options

[friethmiller]

[A softball question for the Ninja and/or others]

This is the cam card that came with my 2357 engine, which was originally built by Rimco/Fat (long block) a few years ago. Can someone explain why with an intake/exhaust of 448, the lift was only set to 327 degrees? I'm about to rebuild my motor and a lot of focus will be directed at piston "deck clearance" and the valve train geometry that wasn't set correctly. Thanks.

[technicalninja]

It's probably showing actual lift of the lobe.

I believe the rockers are 1.3 ratio so multiply by that.

0.327 at the lobe becomes 0.4251 in total lift. Still seems low...

Trying to use a cam card to determine P to V clearance is an exercise in futility IMO.

The clay on the top of the pistons is DEFINITELY something you HAVE to do EVEN if the calculations show clearance!
(IMG:style_emoticons/default/ninja.gif)

What import cam cards seldom show is degrees at ".050"

In my book that number is the best method to compare cams at.

You don't get much actual airflow below .050 lift and the starting/closing ramps can make the cam look bigger than it actually is.

Sadly, that cam has identical lobes for both (exhaust should be more IMO) and it's not asymmetric...

Modern cams have a fast open ramp and a slow closing ramp (helps control valve bounce bigtime). The lobe looks "lumpy" on one side.

I don't like that cam for that motor unless you have heads that don't exist from what I've seen. (have to be HIGH flow on exh side).