Review on 🔧 High-Performance W89409 Valve Spring Compressor for Improved Engine Maintenance by Paul Martindale

This spring compressor works great after modification. The flanges on the ends of the jaws that grip the spring are at a 90 degree angle to the jaws so there is no hard locking under pressure. That means they will slip off as soon as you start compressing the spring. This can only be corrected by curling the lips inward. This requires some strength as the jaws are actually quite strong. Once you do that, they will work just fine. I suppose some valve springs can work without a damper without modification, but you're still better off flexing your jaws.