650 Lift Pac 1905 Dual Valve Spring Kit Including Collets, Retainers, Seats and Seals Suitable for LS1, LS2, LS3 & L98 V8 Holden Commodore & HSV VT-VF Models. PAC racing valve springs employ cutting edge technology in material advancements and processing resulting in superior race track results and reliability. This particular set of dual 1905 valve springs is truly the tip of the spear. 650 valve lift (with 1.7 rocker ratio), you need look no further for the toughest valve springs on the market. This custom kit includes all of the ancillaries required to handle whatever you can throw at it, including 16 valve springs (8 outer and 8 inner), 16 steel valve spring seats, 16 valve stem seals and 32 steel collets. As such this valve spring set is built to withstand the rigors of drag and circuit racing applications, not to mention serious street performance. At Tuff Car Parts we recommend dual valve springs rather than single valve springs for the majority of camshaft upgrades. What is the difference, and why do we recommend duals? A single spring kit is one spring that supports the valve on its own whereas a dual kit has the outer spring as well as a smaller spring inside. The reason we recommend dual spring kits is because in the highly unlikely event of one of the dual valve springs failing, the other spring (typically the inner spring) will still be in tact to hold the valve up and prevent it from dropping into the engine, potentially saving a costly engine rebuild. A single valve spring does not have this second spring to fall back on. So will the PAC 1905 suit my needs? The answer would be a resounding yes if you; 1. Have a camshaft grind greater than. 625 lift at the valve, noting that the 1905 spring copes with up to. 650 lift camshafts 2. The vehicle will be used in burn outs, drift or other situations whereby the engine will hit or sit on the rev limiter on a regular basis 3. The stiffer PAC 1905 dual valve springs help prevent both valve float and valve bounce. Valve float is an adverse condition which can occur at high engine speeds when the valve does not properly follow the closure phase of the cam lobe. This reduces engine efficiency and performance, and represents a significant risk of severe engine damage due to valve spring damage or pistons contacting the valves. They also negate valve bounce which is a related condition where the valve does not stay seated due to the combined effects of the valve’s inertia and resonance of metallic valve springs that reduce the closing force, and allow the valve to re-open partially. Description: LS Dual Spring. Lift Max (in) 0.650. Install Load (LB): 160. Install Height (in): 1.800. Open Load (LB): 425. Open Height (in): 1.125. Coil Bind Max (in): 1.020. Collateral damage is not covered by PAC Racing Springs, and as such cannot be covered by Tuff Car Parts. The item “VE VF Holden Commodore & HSV V8 LS2 L98 LS3 Pac 650 1905 Dual Valve Spring Kit” is in sale since Sunday, October 13, 2019. This item is in the category “Vehicle Parts & Accessories\Car & Truck Parts\Engines, Components\Valves & Parts”. The seller is “tuffcarparts” and is located in Moorabbin, VIC. This item can be shipped to Australia, North, South, or Latin America, all countries in Europe, all countries in continental Asia, New Zealand.
- Manufacturer Part Number: Does Not Apply
- Brand: Pac Racing
- Type: Dual Valve Spring