I have been told that some blocks are better than others. I have 12 Fe blocks in the shed and would like to know how to identify the better blocks. Any help would be appreciated.
In my opinion, with FE blocks, including 390's, it's not necessarily about "Better", it's about the various characteristics they have. Over the 20 years of FE production there were changes over time and some differences with blocks cast at the different foundries.
The main thing to watch for with any FE block is core shift in the casting, which can leave the cylinders thin and possibly control how much overbore a particular block can take. My first advice for anyone sorting through blocks is to pick up an inexpensive sonic tester from eBay. Check your blocks and that may guide you on some you want to keep. We've had a couple threads about the testers here in the past, here's a link to one:
http://fepower.net/simplemachinesforum/index.php?topic=5449.msg58346#msg58346You will want to familiarize yourself with reading the casting "date" codes, since many of the characteristics varied with when a block was produced. Early blocks tended to have the date code on the side of the block, then it was moved to under the oil filter adapter. After FE production started entering it's second decade of use Ford started adding 2 "dots" under the year digit ( the first digit ) of the date code, but sometimes this tends to muddy reading the date if some of the sand from the core fell out of place.
Early blocks - '58-'64, had the two bolt motor mounts, and the earlier ones didn't have the provision for the alternator bolt. They also were a little different in the area of the thrust washer. This may make some of these blocks better for guys doing restorations on something like a retractable or other early FE powered car, instead of a '65 and later vehicle. Motor mounts can be adapted of course, with some fabrication. One note though, many of the '64-'65 FE blocks have the provisions to add the cross bolted main caps, making them desirable for a performance build.
Starting with the '65 model year Ford went to the 4 bolt motor mount bosses on the FE blocks, making them easier to use in a '65 and up vehicle.
Some FE blocks have what's sometimes termed the "2 finger" main webbing and some have a "3 Finger" webbing. many people like the 3 finger webbing better, although it's important to look at the overall condition of any block, and not just let the main webbing decide if a block is "better". Starting with the '73 model year to the end of production, most 390 FE block casting was moved to Ford's new MCC ( Michigan Casting Center ) foundry, these are commonly seen as "501" or "105" blocks for the number cast into the front of most of the MCC blocks. All the MCC 390 blocks have the 3 finger main webbing, which makes some people desire those blocks, however there have also been reports that the MCC blocks may have more issues with internal oil leaks with cracks in the oil passages, so that's something to watch for. Some people also believe the MCC blocks may have less core shift than the earlier blocks, allowing them to be more safely overbored, but I've seen sonic tests of MCC blocks with lots of core shift, so that's not a sure thing. Which goes back to my first point - you really want to sonic test the blocks, don't assume anything.
All this applies to regular 390 blocks, if you don't know for sure where a block originated from of course you'll want to check and be sure if you have any early 390HP or solid lifter Police blocks, or a 391 FT block. FT blocks have some different characteristics too.
Nothing specifically "Better" about a C6ME or C6ME-A 390 block, I think you'll find a sonic test will prove that. They just have the typical characteristics of the time.
"Ribs" on the outside of block casting being a "Service Block" only applies to 427 & 428 blocks, and not 360 & 390 blocks. The "ribs" were just a characteristic of DIF ( Dearborn Iron Foundry ) cast FE blocks starting in the '72 model year and used for a period of time. Since vehicles that originally came with a 427 or 428 were out of production by that time, those blocks had to come from the Ford service or parts dept. But 390's were still rolling off the assembly line in trucks and we've had plenty of reports of people with trucks that have the original engine and have the ribs. So again the "ribs" are just a characteristic of the time they were produced.
Casting numbers on the side of the block pretty much disappeared from DIF cast FE blocks from around the '69-'72 model years, just a FYI. They re-appeared again with the MCC cast blocks. Again, just a characteristic of the time.
The first couple years of 390 blocks, and the earlier FE's, used a camshaft with a thrust button, then Ford switched to using a thrust plate. The earlier blocks can be modified to use the thrust plate and the later style camshaft. The earlier cams & thrust buttons can be hard to find I believe.
Probably some details I'm forgetting lol,
