'63 numbers

[Steve D.]

1) I have not found a suffix to the VIN number (RC, RD etc) which I understand is the engine designation. I have looked at the plates under the glove box. Is there something I'm missing?

2) Block casting # is 3858180. The Black Book lists this as 1965, with the comment "limited use". What might "limited use" mean ? Replacement service, perhaps ?

3) Head casting # is 3890462, with A8 7 below the number. Black Book says '67 , 300 and 350 HP. Is there any significant difference between the '63 and '67 heads ?

4) Rear end # is 3871375. I did not find any prefix or suffix. Any info on this ?

[Duke W.]

Re: '63 numbers

There is no engine code in the VIN field on '63s. The engine code is only stamped on the engine ID pad at the RF corner of the block deck. The 180 blocks were cast at Tonawanda and were used due to a foundary shutdown at Flint - not sure if it was a strike or technical problems. Post what's stamped on the engine ID pad, and the Board can tell you more about the block.

Sounds like you no longer have the original block or heads, but the 462's have essentially the same ports as the 461s.

Not sure about the diff part number.

Duke

[Joe L.]

Re: '63 numbers

Steve and Duke-----

3873175 is the casting number for the differential carrier COVER which was of GM PART #3873174. While this cover will SERVICE a 63, I don't think that it was used in PRODUCTION that early. I'll have to check later. However, I do know that the 3873174 was used in PRODUCTION and SERVICE from ABOUT 1965 through 1976.

You should find the casting number for the differential carrier housing on the side of the main case. Also, on the bottom of the main case, just forward of where the cover attaches, you should find a stamped-in production code. As part of this code there will be a 2 alpha character series (e.g. "AB"). That code will help identify what axle ratio that the carrier originally contained and, possibly, allow us to identify what year the carrier was originally used in.

All 63-79 Corvette differential carrier units will interchange throughout those years. The 63-64 pinion flange is different and, although it will work for all 63-70 with manual trans and 63-67 with automatic trans, the flange, itself, is not interchangeable with 65+ pinion gear shafts. Also, 68-79 with auto trans and 71-79 with manual trans use a different pinion flange, but the flange could be changed to the 65-70 manual trans flange and the carrier assembly otherwise used in a 63-64. So, the point is, due to wide interchangeability there's a lot of potential for "swapping" differential carrier units.

[Steve D.]

Re: '63 numbers

Duke and Joe

Thanks. I'll look for more numbers this weekend.

Steve

[Joe C.]

Re: '63 numbers

Steve:

The "180" block is a Tonawanda small block, which was used in limited numbers in '65,and it is CORRECT FOR 1965-66 ONLY. Check your engine stamp pad - it should read Txxxxyy, where T=Tonowanda xxxx=engine build date, and yy=suffix code (engine type).

Your "462" heads are actually better than the correct "461" heads used for 1963.The "461's" that were used in 1963 had 1.40" exhausts and 1.94" intakes as opposed to the 1.50"/2.02" used in later "461" and "462" heads. The spark plug location was moved very slightly closer to the center of the chamber in the "462" head, which is still a closed chambered design, like the "461".

If you want to build a correct engine for your 1963, I have a set of "461's" dated "G93" (July 9, 1963), and "G123" (July 12, 1963). Let me know- "off the boards" if interested.

Hope this helps.

Joe