First cover is dated March 1970. The timing tab only goes to 8 degrees. This cover has no date code. It reads to 12 degrees. This red cover is an NOS unit dated Oct. 1973. It reads to 12 degrees. Also note the added support rib to the oil pump.
I think the NOS one I used on my last build was like that & had the washer for the dist. hold down. I was under the impression that it was actually a V6 cover but could be mistaken.
COOL, Thanks Steve this is good to know. Thanks for the information. No one seems to look at the 350 engine all that often so its really good to see this.
I have a '73 350 engine in my car with '73 heads. The timing marks go to 12 like the one Steve has pictured. But it doesn't have the support rib by the oil pump. Of course I don't know for sure if it's the original cover to the engine, but likely is. Looks like the second one he shows. Maybe an earlier '73 cover?
You need to find the casting date clock. They seem to be placed randomly. The second cover I pictured did not have one. I thought it might be aftermarket but thought all aftermarket had the bolt on timing tabs.
I have 2 NOS covers (much to my pleasant surprise I think - Thought one was a 455). Neither have a date cast or the gusset. One (1396917) goes to 15° & the other (1396912) to 8°. I'll check on the used ones.
I bought one @ the Nationals a couple years ago and I must've had two when I did my last 350 build - I definitely used one on that engine. I have 2 350's to build eventually and thought I needed one more cover - Both are are basket cases but both engines were supposedly rebuilt before I got the cars so the covers on them may or not be ok. I certainly don't trust either without tearing them down plus I'm sure they're more or less stock rebuilds and that isn't going to fly.
The NOS one I pictured with the 8° (Part #1396912) has that same casting # on a raised boss but casting numbers and part numbers often don't coincide.
Ok, so where would the other number be? The number I posted is in the same spot as the one you show a picture of, above the crank shaft hole. I'm mostly adding what I have just to get more info out there in case it helps decipher parts and year.
I don't know what exactly this timing cover came off of originally but it came on one of the 300's that I bought. Timing marks to 15°.