Wondering if anyone knows what the block I found down the street might be? It has only one cast number in the rear of the block that says "66-427", the bore is 4.05 and there are 8-10 vertical ribs about 5 inches long cast on both outer sides. The guy who has this block also has 7 or 8 more blocks that have no casting numbers whatsoever (other than 66-427) that have 4.13 bores. Could these be some type of service blocks? I about fell over when he said "come look at these 428's" when he opened the doors to his storage shed. There was also a few C6ME-A's with 4.13 bores too! Any insight would be appreciated, as I'm about to chunk the old tired 360 out of the '76.

Chuck

 

Sounds like a herd of 390 and 428 service blocks. They have no casting numbers and do have the ribs you speak of. The 4.05 bore blocks are 390 and the 4.13 428 if standard bore. The date codes are under the oil filter adapter pad. Look for a number/letter/number(s) sequence. 70's service blocks have two dots under the first number. C6ME-A was a 390 and 428 casting number. But with the 4.13 bore most likely a 428 block. You can knock out the freeze plugs and check the wall core thickness with drill bits. A 13/64" drill bit shank will fit snug between the 428 walls. A 17/64" bit shank between the 390 walls. The 66-427 was common to lots of blocks and in most cases does not designate a 427 block. It was just part of the mold that was used for the sideoilers and also used on other block castings as well. Sounds like you should be talkin to that guy for a few blocks. Get the 428 blocks!!!!!!! G.

 

The ribs on the outside and no casting # (like C6ME-A) would be service blocks.
See If he'll part with a 4.13 bore (428) block. The 4.05s were for 360, 390 & 410 cid.
AL.

 

Just got a 66-427 casted on block numbers from a 71 CS, complete truck for $50 with C-6. The block went to the junkyard free.

Carl....=o&o>....

 

There was only one block with the vertical ribs, the 4.05 bore. I figured this one was a 390 service block after looking it up in Christs' book. All the other 4.13 blocks without casting numbers had smooth sides except for two drilled and tapped holes at the #2 & #4 main caps on one side only. All but two of the 4.13 blocks had paint stick writing on them that said they needed 3 or more sleeves. Those blocks had noticable grooves at the tops of the cylinders, but the 4.05 cylinder walls were smooth as could be with signs of carbon on the top 1/4". I don't know much about the cost of sleeving a block, but I was qouted a price of $500.00 each, as is, for any of these blocks. This fellow also has what he says is a 428CJ standard crank with rods he'll let me have for $900.00. Do you guys think that the 390 block with the 428 crank is worth that much to build a 410??? Or should I go for the 428 build? Beemer, where was you when I was looking for a free block? :-)

 

Bad tease sorry. The previous owner kicked a rod because he failed smog, it punched the block and broke a main web. What I have is a 23,000 mile 428 with 7 good rods, 428 crank thats 10/10 mint condition, standard 428 heads, aluminum intake, spare C-6, sold the 3.73 rear. The drive shafts in my truck now, 3" front diameter, my (68) was 2" and I twisted it with the 410. I got the disc brakes for future swap. The truck (71) had 87,000 original miles. It was a gross polluter with the 428 and had to be removed from the road. For $50 I got alot of spare parts. Now if I can find a 427 top oiler block? Another future project.

Carl....=o&o>....

 

$900 is a little steep for a CJ crank and rods even if they are std. CJ cranks are $200-500 and a good set of C7 CJ rods used go for $100+ if that. Sleeves here in CT are $100 a hole complete.The stick writing you mention is this the "A or C" on the back of the block?And the two holes drilled and tapped are how the block was attached to the "J bar" when being assembled. How much is he asking for the blocks? G.

 

FFR the "paint stick" is writing from a machine shop that checked all the bores of all these blocks and they determined that some of the bores on most of the 4.13 blocks need sleeves. The man wants $500.00 per block. There is some type of crude "stick" letter cast on all of these blocks right above the "66-427" casting. The letter is "C". does this mean anything special? What do ya'll think? Which way should I go to have a reliable engine for a everyday driver that might need to do some 5-6,000 lb. towing every so often?
Chuck

 

The "C" designates a CJ or cobra jet block. The "A" is the std passenger car block. If you can get a good "C" block for $500 than can accept the next bore size it a pretty good deal. .060 is about the max you would want to go on a 428. Some will push it to .080 with no ill effects so it really depends on the casting and core shift though. Check out this site for more info on the block. www.428cobrajet.org click on component ID then blocks. It shows the difference between the "C and A" blocks. G.

 

Thank you. That is a great, informative site. I am now starting to lean towards building a new 428. I'm going to get a block off this fellow tomorrow, and I'm going to call DSC in the morning to see if he has everything for the rotating ***'y in stock (prices are a lot better than my local guy). Shouldn't be too hard to break my $4,000 motor budget in the next 24 hours. Thanks again.

 

Glad to help and good luck. Dennis at DSC is great to work with and his prices are very good also. G.