Help cam problem in a 440
HHMMM. The edlebrock springs are a little stiffer than 911s, so they might well be enough. You cant use max lift as a factor when choosing springs. At least not if you want the cam to perform right. That being said..I see a few things..First, setting preload is not a matter of turns. It's a distance spec. Due to machining and tolerances, in many cases, the preload amount for each lifter will require different amounts of truning. You want between .020 and .030" preload on each lifter. DIfferent rocker arms, old millers on the block and/or head deck surfaces, valve job work..All can change that "X number of turns after 0". And stock style lifters can compress slightly just by the weight of the pushrod and arm on them if they are new and full of nothing but air. Preload should be set with the intake valley open, and a wire feeler gage should be inserted under the retaining clip on the lifter to verify the right amount. Once things are hot and the air is bled out, using the "turn method" should work. Also, I find aluminum heads will cool so fast, that I now do one head, then warm the engine up some more, and do the 2nd. I get better results. I also see you used std 10-40 oil. That's a big no-no now. You ned to use either deisel rated oil (like the Rotella everybody likes) or performance oils that will have the zink in them. Also, you should be adding a can of GM engine oil supplement to the crank case before firing. The 305 is a fairly decent size hydraulic. I'm guess the oil is what did it in. Comp now has the break in procedures in the boxes and it mentions Rotella.
As far as a cam choice..a true 10.1:1 with aluminum heads? If the car has manifolds, a split pattern will help. If the car has headers, then single is fine too. If the heads were not as good as Edelbrocks, split pattern can help make up for the imbalance. Same deal extending out to the manifolding or headers. I'd probably have spec'd a milder cam tho. One of my favorites is a Crane H302-2. It's a hydraulic, idles well, and makes very good torque and midrange, while stil being able to spin to 6500. Comp 1st choice would be the XE275HL.