In January of 2005 a group of people who regularly visit the Ford 385 Series Big Block Forum www.460ford.com got together to gather some much needed information about the blocks used during the production life of these engines. People who attended the event brought along production blocks from their own personal collections and those blocks were subjected to a variety of tests. They were weighed, foundry markings, casting production dates and casting numbers were recorded and finally they were each subjected to a through ultra sonic check of each bore in 12 positions to determine and map cylinder wall thickness. At the Block Summit Charlie Evans took some time to give a seminar on Big Block Ford cylinder heads covering not only their intended applications but also the finer points of modifing them needless to say it was both informative and entertaining. Jay Cornell and the rest of the folks from IDT also made the trip down from Michigan bringing along with them some samples of their product and some of their sand mold patterns for everyone to see. Jay used them to explain the casting process to everyone and what it takes to make a block from scratch. After hearing about the whole process I found it completely amazing that a manufacturer such as the Ford Motor Company could make blocks not by the tens or hundreds but by the thousands and millions.
What everyone hoped to find was a particular series of blocks that could be utilized for large overbores without fear of producing a block with overly thin cylinder walls. It is common to bore these engines .080 oversize to a finished bore diameter of 4.440 inches. Some builders have even bored as far as .140 oversize for a 4.500 finished bore diameter. These bore sizes along with a stroke of 4.500 inches make engines of 557 and 572 cubic inch displacement, all from a regular production block casting.
The day of the event 35 blocks were put to the test. The big block Ford had a production life from 1968 till 1996 and it was used in nearly all Ford fullsize cars and trucks during that time. Block castings from every era were present, C8VE-A,C9VE-A,DOVE-A,D1VE-A2A, D1VE-A2B, and D9TE blocks were tested. There were several Cobra Jet and Super Cobra Jet blocks with four bolt main caps and even one Boss 429 block in the mix. Blocks bearing marks from these 3 foundrys were all present at the block summit. The foundry marking is on the block at the top rear near the oil pressure tap boss. The marking that looks like CCP is the Cleveland Foundry, DIF is the Dearborn Foundry and finally MCC is Michigan otherwise known as the Flatrock Foundry. From what could be determined from the block summit data what that blocks were originally cast at Dearborn Iron Foundry at least until the D1VE and later castings when production was moved to Flatrock. Blocks were produced at Flatrock until the introduction of the D9TE block for 1979 when production was moved to Cleveland Cast Products till the end of production. What is interesting is how each foundry used unique tooling to produce the blocks each of which having unique and often special features. For instance, the DOVE-A blocks produced in the Dearborn foundry are the only ones cast with extra thick main webbing to allow for the factory instalation of 4 bolt main caps. Not all of the DOVE-A blocks have 4 bolt mains but they all have the provision for them. The D9TE blocks are cast with a cylinder wall that's .250 longer than other production blocks and this is an interesting feature. It's not known why the factory changed this but it is certainly a plus if long strokes are being run, giving the piston more support at BDC. (4.500 stroke 6.700 rod combinations work fine in all production blocks) SVO blocks also have this feature. Not to be left out, the D1VE blocks from the Michigan/Flatrock foundry are the most numerous and they were used in 429 and 460 production from about 1971till 1978.
Other production block features are: C8VE,C9VE and DOVE blocks all have a narrow pan rail. D1VE blocks can have a narrow pan rail but only in the AA version. AB or A2B blocks have a wider or unreleaved pan rail as do all D9TE blocks. Some DOVE-A blocks are cast with a large "A" on a square boss at the front of the block. Many of those particular blocks are also cast using Boss 429 bulkheads front and rear. This bulkhead has slightly more material under the front main cap than the regular bulkhead. Not all "Boss 9 bulkhead" DOVE-A's have the large "A". The rear bulkhead appears to be identical to other blocks with the exception of additional bosses near the rear cam bearing bore. In the actual Boss 429 block this additional material was used to accomidate the Boss 429's unique oiling system and also a bolt on cover instead of a drive in plug for the rear of the camshaft. None of the DOVE-A blocks are tapped or machined any different than regular production blocks in this area.
All of the blocks were weighed and while there were differences there seemed to be no real rhyme or reason to the variance
Ultra sonic thickness testing was what was hoped to reveal
any secrets making some of the blocks, one particular casting
more desirable than the others. After testing over 30 blocks,
none were found to be universally superior in the area of cylinder
wall thickness. Some were thicker and some were thinner than others
but no particular casting number, date code or foundry could be
deemed the best for large overbores and or cylinder wall thickness.
All of the data was carefully recorded and is presented here:
Watch
out, this file is about 1.8MB
When reading the data sheets the information is arranged as listed except that the cylinders were measured at 4 places around the bore but at 3 instead of 2 different depths. So, the first number listed at each position is at 1 inch depth. Then the number after the "/" is the reading from 2" down etc.
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