![]() ![]() The T legged stands are generally considered too weak. The U shaped stand is rated to 1250lbs - the minimum for working on an IH. Notice the engine stand's legs are a "U" shape, not the typical "T" shape. The biggest speed benefit was that I now knew how long I needed to use the grinding stones before I moved on to the 40-grit cartridges. I should also mention that it took an entire month of evenings to get the first head ported! I spent only 2 weeks doing the second head - it wasn't as nicely done, but adequate. I could have put forth additional effort to clean up the valve pocket area and to work a little at unshrouding the valves, but this is my first porting job, and I was leery of making anything worse than it was originally. I then proceeded to remove a little material - primarily cleaning up the chamber and removing the high spots, and then worked my way to the 80-grit, the 120-grit, and then the polishing attachments until the chambers were rather bright. ![]() I then moved to the combustion chambers, and installed the rustiest pair of valves from my spare set of heads. Once the worst was taken care of, I moved on to the 80-grit, then 120grit, and then the final polishing "flap wheels." I then moved on to the 40-grit and then 80-grit "cartridge rolls" and worked to smooth the entire exhaust port area - specifically where the humps had been removed. I used the large grinding stone to completely remove the "humps" from the exhaust ports. My heads were not drilled for the air-injection tubes, but "smog" heads would be. My engine wasn't a "smog" motor when it first started life in 1977, and it's not about to become one, either. These are specifically to accomodate air-injection for smog engines. IH heads have a large hump protruding from the top of the head in the middle of the exhaust ports. I concentrated my efforts on the exhaust ports. I used the porting kit from Standard Abrasives in my 1/4" air powered die-grinder. I have plans to replace it with a larger unit, but those plans won't happen until after this engine is done. My air compressor is a bit under powered for the job (an old industrial 1HP compressor I bought for $100). While everything was being balanced, I continued to port and port and port the heads. The 392 connecting rods are assembled to the hypereutectic. The bill was $25 to resurface the flywheel, $175 to balance the reciprocating assembly, and another $32 to install the pistons to the rods. Within a week, I was $232 poorer, with a pile of balanced engine parts. I dropped the pistons, rings, rods, crank, harmonic balancer, and flywheel off at the second machinist with instructions to balance the assembly, and to resurface the flywheel. I finished part 1 with, "The next installment - porting the heads myself, painting the new engine, fitting the various pieces together, and machining the intake for my new induction system." ![]()
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