photos and text by: Michael Scano
We Put the MS Racing Components VVT Unlocker to the Test
JTM Motorsports’ quest for more power from their 2015 C7 Corvette shop car lead them to develop a custom camshaft package for the GM Gen V LT1 engine family. The goal from the onset was to retain the benefits of Variable-Valve Timing (VVT) Technology.
Upgrading to a high-performance VVT camshaft or developing a custom VVT camshaft profile with increased duration/lift piston to valve (PTV) clearances becomes an issue, especially with the exhaust valve when the camshaft is fully in the retarded (counter clock wise) position. The high performance aftermarket currently only offers VVT cam phaser limiter kits. However, actual PTV clearance measurements are not known using these limiter kits and PTV can’t be measured since the cam gear phaser is locked without engine oil pressure.
VVT cam gear phases are computer controlled using pressurized engine oil. Without oil pressure, the VVT cam gear phaser is locked advanced making PTV clearance measurements in the full camshaft retard position impossible.
That is where MS Racing Components comes into the picture with their patent pending VVT Unlocker line of tools. The MS Racing Components VVT Unlocker allows for quick and easy unlocking of the VVT cam gear phaser without damage. With the cam phaser gear unlocked, it can be rotated counter clockwise (cam retarded) so PTV can be measured and verified.
JTM Motorsports was able to measure and verify the PTV clearances of their custom camshaft package using the MS Racing Components VVT Unlocker. Customers who purchase the custom camshaft package have a piece of mind that sufficient PTV clearances have been maintained while retaining the benefits of VVT Technology.
Rick Seitz is the owner and founder of GMEFI Magazine, and has a true love and passion for all vehicles. When he isn’t tuning, testing, or competing with the brand’s current crop of project vehicles, he’s busy tinkering and planning the next modifications for his own cars.