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Dual Valve Springs

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Our Trick Flow heads came partially assembled with dual valve springs. While we like this arrangement, we decided to change it for fear that we might get into valve bounce at higher rpm. "Valve bounce" is an adverse condition where the valve does not stay seated, due to the combined effects of the valve's own inertia and spring resonance during the valve closure phase. Valve bounce can effectively reduce the closing force, allowing valves to reopen partially, which is highly undesirable. Trick Flow claims the springs supplied with our heads would handle upwards of 6,500 rpm. However, we plan to spin our engine to 7,000 rpm on occasion when we hit the nitrous in mud and sand, so to ensure our valvetrain would survive the abuse, we swapped in a set of lightweight Beehive springs from Comp Cams (PN 26986-16). If you consider how fast a valve spring and its retainer move at high rpm, you can appreciate why shaving off an ounce here or there can really affect things. This shot shows the two different types of valve springs, side by side. Notice the smaller dimension of the top portion of the Comp Cams spring on the left. This tapered or "Beehive" design allows for less spring mass and it uses smaller and lighter-weight retainers. The end result is less weight. We weighed each arrangement and found the Beehive design to weigh 50.6 grams less than the traditional Trick Flow dual-style springs. A lighter-weight valvetrain will allow the engine to rev up more quickly, giving it that snappy off-idle throttle response everybody likes.