I've stumbled upon an old 390, I believe, with the aluminum ID tag on the front of the motor. I've looked all over the forum here, and can't seem to find out how to decode the thing. Can somebody help?

390 68 10
8 F K 343 J

Thanks, Appreciate it,

b62

 

It's a 68 390. Well the tag is anyway. There should be a letter after the 390 which is the plant code. 68 is for 1968 and 10 is the change level. The bottom line is missing some thing. 8 is for again 68. F is the month for June. Then there should be a number which is the production date. K343J is the engine code and change level. There should be a number after the J also. Tags can be removed and replaced so check the bore and stroke to verify the 390 tag on it. I'm not really up to snuff on my tag decoding but this is the basic skinny of things. G.

 

Forgot to mention the block casting number might not do any good here but the casting number off the heads will. FE blocks have generic casting numbers through 68 and after. The heads however can be easily ID'ed. Head casting number is between the center two spark plugs. Date code for the heads is above the casting number under the valve cover area between the center two valve springs. Block date code is below the oil filter adapter on a small angled part of the block. Look for a number/letter/number(s) sequence. This is a good way to see how original everything is. The engine tag is a good sign. The engine might be fairly original if the tag is still there. Or the last owner was good enough to include the tag when rebuilt. G.

 

Thanks G,

Good, I thought that it was incomplete, based on the info that I could obtain. But that is all of the ## on the tag. I didn't think to get the casting ## off of the heads, I just thought that everything I needed was in the tag information.

Thanks nonetheless,

b62