The Long and Twisted Tale of a 383

This engine has been a long time in the making. I believe talk of building this engine began around 2002-2003. We had a spare 4 bolt main block out of truck that had massive oil consumption issues due to broken piston rings and bad valve stem seals. Being that it was a 4 bolt main block, we wanted to build something a little more special than a run of the mill 350. We decided a 383 would be a fun engine to build and we began to gather parts. It took almost all of 2004 to get the parts together and have all the machining done. The block was boiled, then painted with Chevy orange on the outside and Glyptal  in the lifter valley.  Glyptal is a paint that is normally used to coat the windings in an electric motor, however engine builders use it to make the oil flow down the lifter valley quicker. A local machine shop bored and honed the cylinders, and line honed the mains.  By December 2004 we had all the parts we needed and were ready to assembly it. We added the heads and a partial valve train around 2006 and it has sat in silence since then. Below are some of the details of the assembly of the short block.

It’s based on a 4 bolt main truck block that was pulled from a 3/4 ton ’86 pick up. The rotating assembly consists of an Eagle 5140 steel crankshaft, Eagle H-beam rods, and Speed  Pro hypereutectic pistons. The Block was bored, honed and painted. The mains were line honed with an ARP main stud kit installed. The bottom end is very stout, and should handle pretty much any cam/head combo we could dream of.

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The bare block with bearing halves installed

The aluminum plate near the rear seal is an adapter that allows you to use a two-piece rear seal crank with a one-piece rear seal block. This saved us a lot of money because one piece forged stroker cranks are very pricey.

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The Eagle rods are very nice, but required a fair amount of work to make sure they clear everything. Like most stroker cranks we had to clearance the block near the oil pan rails. To do this I installed the crank with a set of bearing and one rod. When the rod hit part of the block I remove some of the block material with a die grinder. When ever you are grinding in that area you need to be careful, if you grind too deep you can run into an oil rail and ruin your block. I also had to clearance some of the rods so that it would clear the camshaft. One thing I forgot to do was check the oil pan for clearance.  We bough a real nice Canton road race oil pan off eBay, it has all the stuff you want in a pan, trap doors, scraper, windage tray etc. When we were doing the final assembly of the engine we noticed a scraping sound when rotated the crank. After a bit of head scratching we realized it must be the pan. We took it off and sure enough there we scrape marks from the crank. A few well placed hits with a hammer and the crank spun freely.

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We used file fit rings on the engine. It was a little tedious gapping all the rings, but it will be worth it. Properly gapped rings seal better, reduce blow by, and stop oil consumption.

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The rods had bushed ends, which means the piston pin is floating. The lock you see keeps the pin in place. These aren’t as good spirolocks, but are way easier to put in and they came included with the pistons.

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The completed bottom end, ready for the cam and heads.

We went with vortec heads for this engine as they flow extremely well for their price. A light port and polish job was done to them in addition to port matching them with the intake. The heads were installed with ARP bolts and a steel shim gasket to bump the compression a bit.

This should bring you up to speed on the engine in its current state. The next post will detail some of the trouble we have had with the valve train, namely the cam springs, push rod lengths, and rocker arm clearance.

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