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Aug 17, 2006 | 08:57 AM

#16

mswift

Senior User

Joined: Sep 2004

Posts: 457

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I have a block sittin' in the barn that has these "ribs" on it also. When I tried to find info out about mine, I couldn't get a definet answer, but most likely it was a service block of some sort. Also, if I recall correctly, my block shows no signs of a casting number.

Keep posting what ya find out. Maybe we can get to the bottom of these ribs.....

Aug 19, 2006 | 10:18 AM

#17

FFR428

Needsmorecoffee.

Joined: Oct 2004

Posts: 3,624

Likes: 2

From: CT

Those ribs are on some late 69 and 70's service and production blocks. Some say to reinforce the block and some say to heal up the aging FE molds that were close to the end of production. The blocks date code will tell you the exact date. All the 70's era service blocks I've had also had those ribs on the blocks. Seems some 70's truck blocks also used the ribs. Both DIF and MCC castings. I'd have to say with C1 heads the engine was pieced together. The 63 406 block I had did not have those ribs. Also early blocks (63 and earlier) had the two bolt motor mounts vs the later 4 bolt pattern. On the date code if you see 2 dots under the first number it's a 69 or later 70's casting. Also none of the 70's service blocks i has used a casting number either...just a date code, 352 and mold numbers and DIF foundry logo.

G.

Last edited by FFR428; Aug 19, 2006 at 10:20 AM.