Okay – so you have already determined that 14093638 is a 350 2/4 bolt main and flat or roller cam. The V0202USA adds more clarification, i.e., made in Flint on the second day of February and the USA tells us that it was originally a 165 horsepower engine destined for a 1983 truck. It is not a Vortec engine.

That was its original configuration when it was built on the line in Flint in 1983 – in the 28 ensuing years, any number of modifications could have been made. Bear in mind that blocks with that casting number all have the cast-in provisions for GM’s roller setup however; GM only performs the additional machining on some to install roller cams. The rest do not receive additional machining and received flat tappet cams. Same for the two versus four bolt caps and the only sure way is to open the engine up. Again, in 28 years, a lot could have been done to this engine and that’s probably why numbers don’t line up.

Typically trucks of this vintage received a flat tappet and for the ¾ ton and heavier chassis 4-bolt mains - just a guess based on taking a few of them apart.

You asked if GM “ever” put roller rockers in roller cam engines - well “ever” is a long time, but I have not seen roller tip rockers stock. I’ve seen a ton of PRW aftermarket types where people have replaced the stockers with 1.5 or 1.6 roller tips, but never stock.

That said – I have seen some strange things come out of GM – like high performance, steel crank with a 350 part number in a 305 engine, dual spring big valve heads on otherwise tame engines, high strength “pink” rods on a stock engine, etc. What occasionally happens toward the end of a production run is a shortage of the exact “stock” part and the factory boys on the line will “upgrade to the next highest assembly”. The 305 and 350 both have a 3.48 stroke but the 350 forged steel crank was not intended for the “lowly” 305, yet it will work just fine and no one will be the wiser until the day the engine is opened up and a trained eye catches something that doesn’t look quite right. It’s possible that your truck motor started as a roller cam short block and got drafted to fill a temporary shortage on the truck line as the “upgrade to the next higher assembly” which could explain the mismatch of internals from the factory.

Tell us what you want to do with this engine. Share your “dream machine” plans and let us become engaged with your project. We’d like to help and this site represents the best hot rod minds to be found anywhere. As for the rub – please don’t use bold, capital letters – no one here is trying to offend or patronize, but bear in mind – we can’t “see” what you’re talking about and pictures help a lot. The gentleman you flamed has a lot of experience and you’ll notice over ten thousand posts here. He knows his stuff and we’re just “getting to know you...”

Regards,
Glenn