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Discussion Starter #1
Okay, so I am pleading ignorance, and I am needing help figuring out just what I need to do to go forward. I had the 1989 SC engine block bored .030", decked the block, milled heads, valve job, new cam bearings, and had them assemble .030" pistons on the rods. The mains were .010" as were the connecting rod journals, according to my paperwork. That was back in 2009. Well a lot has happened since then. My T-bird body was beyond saving, so the engine sat in my pole barn. My wife really loved the car, and I lost her to cancer in 2012. I kept the engine with the intention of an engine swap into a Mustang convertible I already had.

Fast forward to now. I started getting ready for the engine swap and decided to disassemble it and check everything out, especially the connecting rod bolts. Well I got busy and decided I would have the crank checked to make sure everything was good. I took the engine shortblock to a local engine builder and he finally called me after 2 months. He said that the mains were not all the same size, the rear was .020" and the rest were .010" undersize. So without questioning him further I said, "do what you have to do to fix it and order me new bearings (see above -my original machine shop said they were all .010")." He had trouble finding me bearings, I think because Ford did not recommend machining the rear journal (we all know why, eg. the NA cast crank vs forged SC crank). So I ended up buying a new crank. He also said the pistons pins did not require clips, so he removed those too and put them in a zip lock bag. I don't remember back in 2009, but the pistons clips came in the parts kit, I am pretty sure. The pistons are nothing special, just OEM 8.2:1, .030" oversized.

So, what I need to know is, do the OEM pistons need the clips on the Piston pins? I'm going out to my pole barn today to do some work and I'll take pics. Any pics or advise would be appreciated.

I believe they are a sealed power Hypereutectic Pistons by searching the number stamped into the top of the piston. As I said, the engine builder removed the C clips, they are in a nice little ziplock bag.

:unsure:
 

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The one main bearing being .010" smaller was done by Ford to prevent accidentally installing the NA crank in the SC. The previous machine shop probably cut all the bearings .010" under what they were, which left the rear-most bearing .020" smaller than the original size of the front 3. The new machine shop is obviously not familiar with SCs, and so he didn't know that, but if you got a new crank, then that issue should be resolved. As for the wrist pin clips, 89-93 SCs used pressed in wrist pins, which don't require the clips. 94/95 SCs used full floating wrist pins, which do require the clips. If your engine was rebuilt with 94/95 rods, or if the previous machine shop bored out the small end of the rod and bushed it for the full floating type, then it will need the clips. It is simple to tell. If the wrist pin can move in the rod end, then you need the clips. If it doesn't, then you don't need them.
 
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I found another issue. I was planning on buttoning up the camshaft and installing the lifters and timing gears/chain today. I used assembly lube on the camshaft, and everything went well. However, when I put the thrust plate on and torqued it to 10ft lbs. I noticed that the camshaft was binding between 270- 360 degrees when I turned it. I didn't install lifters so that wasn't the problem. I did notice that the gap between the Camshaft and the thrust plate was not equidistant. I loosened the thrust plate and it turned again without binding. I've included some pics of the thrust plate that looks to be buggered up in some spots. That still doesn't solve the problem of the non concentric gap. Suggestions? Could the original machine shop bought the wrong camshaft? The number on the back of the camshaft is 2790 B and is stamped with MAP. I'll check for the concentricity of the camshaft later. I am really doubting that's the problem.
 

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