Piston Ring Squaring Tool, 4.000 to 4.230 Bores

Squares your piston rings in the cylinder bore for file fit measurements. Fast and easy way to ensure your rings are square in the bore before measuring. More precise and easier to use than using a piston to square your rings in the bore. Dual sided tool made from 6061-T6 anodized aluminum for long service life. Suitable for bore diameters from 4.000” to 4.230” depending on side of tool used. Piston ring tool can be used with cylinder head studs installed. Proper Ring Gap Is Critical to Engine Performance; Our Ring Squaring Tool Makes the Job Easy Building an engine, no matter if it is a low-buck cruiser or a high-end race engine, ensuring your piston ring gap is measured and adjusted for the performance expectations of that engine is vital. Piston ring end gap must be measured in the cylinder bore of the engine the rings are being installed into. It has been common in the past for many an engine builder to simply grab a piston and use it to push the piston ring down into the bore. While this may have worked, there is little to guarantee that the piston ring is truly square in the bore for a precise piston ring end gap measurement. Like any job, using the proper tool to get the job done will save time and provide more accurate results. This is why a piston ring squaring tool should be a part of your engine building tools collection. Our piston ring squaring tool is made from durable 6061-T6 aluminum and is anodized for good looks and lasting protection. We designed our piston ring tool to work with a cylinder bore of 4.000” diameter up to 4.230” diameter by providing two different bore sizes in one tool. Simply flip the tool over to use applicable fitment for your engine block. For smaller bore engines, such as the popular LS, we offer a piston ring tool sized to work with 3.736” to 3.810” cylinder bores. The piston ring squaring tool provides the user the ability to seat the piston ring tool quickly and easily to the block surface to position the piston ring in the cylinder’s bore. The open center of the piston ring tool allows the user to reach into the bore and pull the piston ring up against the piston ring squaring tool, confirming that the ring is indeed square in the bore for measuring with a feeler gauge. The outer diameter of the piston ring squaring tool allows for use on blocks with head studs in place/installed as well, saving you further time of having to remove your studs to check and set piston ring end gap. Note that this piston ring tool is only designed for squaring your piston rings in the cylinder bore and is not a piston ring compressor. We offer piston ring compressors in six different size ranges to safely compress your piston rings and aid in installing your piston and rod assemblies.