Opinion of LS3 small EPS cam dyno results
#41
#42
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TECH Junkie
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From: Casselberry FL
I sent the graph to Geoff @ EPS and spoke with him about 20 minutes. He honestly doesn't see a problem with the dyno graph given the valve events and said the top end of the graph doesn't indicate weak springs. He isn't a fan of the beehives/conicals either, so that reinforces my plan to switch to BTR's on the next spring change.
#43
I hit 465/446 (SAE corrected) with a stock LS3 and a 227/243 cam a few years back. This was with ARH 1 7/8 long tubes, cats, and an SLP dual dual. MHO, your exhaust could use some opening up (more headers than cat back) but it's not ruining you. Looks like you're getting good advice from Tick, listen to it. For reference, this same car did 345/345 with a bolt on LS1 and the same exhaust on the same dyno.
Beehive springs usually don't fatigue at the same rate as higher pressure dual springs. Since a beehive spring normally has less spring pressure than a comparable OD diameter dual spring, they don't create as much heat. Heat is created via friction from compression of the coils. Heat is what fatigues the coils and causes them to lose spring pressure. How quickly or how slowly that heat dissipates due to the OD diameter of the spring also plays a part as does RPM cycles and lobe design.