I dont know what is heavy or light. The guy that built my heads looked at cranes catalog so thats what he used. When I was looking at the estimate while doing the heads I saw the $256 springs. I asked him why. He said thats what crane recommended for marine duty. Is this going to ruin my motor?

You should have about 350lb at full open.

Id be calling crane first thing in the morning and demanding a new proper set of springs be sent asap. And be sure to explain the misinformation you were given, whether over the phone, or their catalog misprints. Even in my catalog, their spring upgrade part #, doesnt come up anywhere, as if it doesnt exist, and your catalog, they are showing the hydraulic roller 99896 spring that they recommend on their hyd ROLLER cams.

I know it sucks, but better catching it now before damage is done. Not only is it too much spring from a lifter standpoint, its too much for a typical cast core. That spring is better suited to a billet steel cam core

X 3.

Ruh roh shaggy.

Did you by chance fire up these engines already ? Hope not.

Very good chance the cam will be junk with those springs, and probably collapse your typical hydraulic flat tappet plungers.

The std 99893 spring, would have 130 seat, and about 320ish open, which is about right on for a bbc hyd flat tappet perf cam. While they may offer a better quality spring for marine, the pressures are the pressures

Good catch you two.

This is why people are buying outboards and pontoons.

The engine has not been fired yet. It was bolted on the dyno today. Maybe the shop it is at will have a set of springs that will work. Then we could just swap them there.

Sorry dude. You still have your old valve springs from the 420 setup?

No they were shot.