What some MAY be missing is the fact that normally ANY of these cast pistons, IF you pay attention to the details, will almost NEVER give you anywhere near the original stock compression ratio. Now mind you the BEST I have EVER measured is 9.75-1 from the factory. This is with the piston in the hole about .040" which is RARE. Most are in the hole about .055", now 9.5-1. Most of the cast replacements are in the hole .065" +. Now about 9.3-1. Add the thicker Fel-Pro composite gaskets at about .039" compressed you lose an additional .77-1 compression. Now your at 8.5-1. I was just told the Best gaskets are about .050" compressed. I think they are advertised as .033" compressed. Unless they have diff. ones available. Now the ratio is even less. Then the con rods are re-conditioned which makes them shorter by .001"-.002" To get back some of this lost static compression ratio there are a variety of things to do. 1st. is decking the block. At an additional cost of course, cutting the heads more to make a smaller combustion chamber, at an additional cost. Now this EXTRA material removal will likely end up with port mis-matching, especially with the intake manifold & water manifold. Now you have the possibility of the outer edge of the pistons domes coming into contact with the head. You need to take off additional material from the edges of the domes & this will lower compression even more. Then you have the additional cost of the original shim steel head gaskets which are becoming more not readily available as time goes on & will become more costly in the future. Then something MANY don't even think about is the squish/quench area. From the factory, normally, they are .055" in the hole & with the shim steel gasket at about .015" compressed the quench/squish area is .070". Our "Nails" seem to run best with about .025"-.050" squish. Ever wonder why one "Nail" ran better than another when they were new. It probably had something to do with the piston sitting in the hole closer to .040" as opposed to .055" as is normally found. When the squish is correct the engine has a better chance of resisting detonation problems. Some times you cannot hear this as it's so slight.
Now after doing all of this to get things as correct as possible, with the cost of the pistons, rings, additional machining operations & the cost of shim gaskets your pretty close to the price of my custom forged pistons, including rings. Then you have the additional insurance that a forged piston has over a cast piston. Plus the additional features that have been designed into this forged piston.
Each set is built to each individual engines specs. Unfortunately I NEED ALL the specs. Once I have all the specs it is about a 2wk. turn-a-round. Single sets cost additional $$$$ so getting five sets done at one time can be a savings.
Tom T.
