My catalog shows the 60405 is a fast rate hyd cam in the Voodoo series.
Again, looking in the catalog........I’m seeing they show the non-premium valve spring to be a 73195, which is the same spring as the Comp 995.
This is a 402lb/in spring designed for the short installed height of the stock head.
Now you added 1.6 rockers to the mix, which requires increased spring load to achieve the same rpm that those springs would reach with a 1.5RR.
You need more spring than what’s recommended to compensate for the higher rocker ratio.
There is no mystery that the current springs, which are set up with less load than the recommended spring, and have a lower rate as well, aren’t allowing the motor to reach a very high rpm before the valvetrain becomes unhappy and the motor lays down.
100lbs on the seat isn’t going to get it done with that cam and that RR.
I’ve been testing motors on the dyno since 1990......... I see this **** play out all the time.
Put in the bigger springs, then iiwii.
If you need more....... swap to a solid.
Mild-Mannered 440 Mauler - Dyno Test - Mopar Muscle Magazine
