I'm finishing up a Mark IV BBC using a Jones 224 @ 0.050" 0.330" lobe lift HFT cam. I've read both of Vizard's books where he promotes the LS style beehive for street BBC's with HFT cams. I actually purchased a set of PAC 1218 springs with matching locators and retainers and confirmed fitment on my cylinder heads. Before install I called PAC tech to better understand longevity of these springs in a street application. During the discussion I mentioned I also had a set of Comp Cams 924 dual springs. The PAC tech did not recommend their beehives for this installation. In fact, he suggested I return the PAC beehives and run the Comp 924 duals for my application.
My Comp 924's measured spring rate is 330 lb/in, slightly lower than the advertised 347 lb/in. I want good valvetrain control to 6,000 rpm. Intake valves weigh 133 grams and exhausts are about 125 grams. Mike Jones suggested I set these up with 125-130 Lb seat load, which I did. I have a set of Crower Enduro stainless 1.7 ratio rockers. I recognize these are overkill for this application, but I don't have another use for them. The actual ratio is higher than advertised, providing 0.580" valve lift with checker springs. Open spring load with the Comp 924's will be about 315 lbs.
I understand there have been advances in valve spring tech over the last few decades. I'm curious whether there is a better option than the Comp 924 springs for my application. I'm particularly interested in a little less open spring load for increased longevity. Thanks everyone.
BBC HFT valve spring options
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