1966 muncie numbers/dates

[Joe T.]

I have an early 66 327/300hp roadster, I've got correct casting numbersand dates on engine, rear end,starter, alternator, radiator. I have correct casting number on transmission(3885010) but I believe it is a replacement trans with date P1202. There is a transmission on EBAY with 3885010 cast number and P0908 date but seller says is is from a 68 vette. My questions are-how important judging wise are the transmission dates and how can you tell if a 3885010 transmission was made in 64,65,66,67 or 68 assuming there is no Vin number and the P0908 code does not have a number a letter for the year and month? I'm not sure as I get ready for judging that I should spend big money on a correctly dated transmission case, thanks Joe

[Joe T.]

Re: 1966 muncie numbers/dates

this vette has build date oct 6,65

[Wayne M.]

Re: 1966 muncie numbers/dates

I have an early 66 327/300hp roadster, I've got correct casting numbersand dates on engine, rear end,starter, alternator, radiator. I have correct casting number on transmission(3885010) but I believe it is a replacement trans with date P1202. There is a transmission on EBAY with 3885010 cast number and P0908 date but seller says is is from a 68 vette. My questions are-how important judging wise are the transmission dates and how can you tell if a 3885010 transmission was made in 64,65,66,67 or 68 assuming there is no Vin number and the P0908 code does not have a number a letter for the year and month? I'm not sure as I get ready for judging that I should spend big money on a correctly dated transmission case, thanks Joe

Joe -- checking that eBay listing, I see it's got a VIN derivative stamped on the maincase driver side rear [looks like (6?)_L_space 1937]. This will cosmetically cancel the credit of having a P0908 assy. date on the other side. Also, has a '429' tail ('64-5 or non-Corvettes, Pontiacs, 66+), so you'd have to swap that. It has a 3950306 sidecover ('69-only) number; (should be 3884685 for '66-68) but it has the bolt-lever attach type rather than stud-lever ('68-up sign) .

Looks like a nice clean unit, but like most eBay muncies, are put together from parts from many original units.

If I'm reading the flight judging manual (for '65) correctly, only the maincase and sidecover casting #s are judged; no VINs, dates or tail house casting #s (yet; maybe in future flight judging, when they can raise the car or slim-down the judges ).

IMO, this is a lot to pay just to get a correct date on a maincase (and we don't even have a good pic of that). Keep looking; there's a lot of 010 cases on eBay; then just transfer your internals.

[Henry S.]

Re: 1966 muncie numbers/dates

Hey Joe, Not looking to hijack your thread but I have a similar question. My December 28, 1966 Roadster is a 1967 327/300 also with a replacement Muncie in it. Case # is 3884685 with 3857584 tailstock. Date code is P0M11B. Patend # 3088336. I'm assuming I would want the same numbers as yours except a late 1966 year date like P7TXX with the "T" being December and XX being the day. Is that true or would case and tailstock number be different also.

Joe, I have been checking Ebay for a couple months and as Wayne mentioned there are several 010 cases out there for sale. Let me know what date you need and I'll keep my eyes open for you. Good luck, Shooter

[Joe T.]

Re: 1966 muncie numbers/dates

thanks, I would need the 3885010 casting number and the code I believe would be P08-- or P09-- where the -- would be the day of the month, so a build date of August or September 65 for an early 66 (Oct,6,65 car build date)

[Wayne M.]

Re: 1966 muncie numbers/dates

... I have a similar question. My December 28, 1966 Roadster is a 1967 327/300 also with a replacement Muncie in it. Case # is 3884685 with 3857584 tailstock. Date code is P0M11B. Patend # 3088336. I'm assuming I would want the same numbers as yours except a late 1966 year date like P7TXX with the "T" being December and XX being the day. Is that true or would case and tailstock number be different also.

Henry -- you'd need the same 010 maincase P7S or T, and 584 tailhousing (which you already have). You say your maincase is # 3884685, but that's the sidecover # for '66-68. Maincase # is top row on passenger side. Now with an assy. date code of P0M11B (Muncie 4-speed, 1970 model year, August 11th, close ratio), is your maincase # 3925660, or 3925661 ? If it's a 660, I'd expect to see P9Mxxy for late '69 model year production due to strikes, etc. within the Chevrolet assembly lines. Maybe it's early 1970 model year for some GM assy facility that started 70MY production in Sept of '69, and was not affected by the strikes. Maybe it was an over-the-counter sale. A lot can be determined by reading the VIN derivative, if one is stamped by the P stamping.

[Henry S.]

Re: 1966 muncie numbers/dates

Henry -- you'd need the same 010 maincase P7S or T, and 584 tailhousing (which you already have). You say your maincase is # 3884685, but that's the sidecover # for '66-68. Maincase # is top row on passenger side. Now with an assy. date code of P0M11B (Muncie 4-speed, 1970 model year, August 11th, close ratio), is your maincase # 3925660, or 3925661 ? If it's a 660, I'd expect to see P9Mxxy for late '69 model year production due to strikes, etc. within the Chevrolet assembly lines. Maybe it's early 1970 model year for some GM assy facility that started 70MY production in Sept of '69, and was not affected by the strikes. Maybe it was an over-the-counter sale. A lot can be determined by reading the VIN derivative, if one is stamped by the P stamping.

Wayne,
Thank you for your help. I don't have the main case written down, I will check it over at the shop tomorrow. I do have a number written in my book that is 3858403 but I have it marked as either the bellhousing or inspection cover. Does that make sense?

Thanks,
Henry

[Wayne M.]

Re: 1966 muncie numbers/dates

.... I do have a number written in my book that is 3858403 but I have it marked as either the bellhousing or inspection cover. Does that make sense? Thanks,
Henry

Henry -- that's the bellhousing, and would be correct for your car.

[Joe T.]

Re: 1966 muncie numbers/dates

how can you tell what year the 3885010 transmission case was cast prior to 1966 which I believe is when the year code was added, i.e. my 3885010 case has P1202 date, could this be 64 or 65?

[Wayne M.]

Re: 1966 muncie numbers/dates

how can you tell what year the 3885010 transmission case was cast prior to 1966 which I believe is when the year code was added, i.e. my 3885010 case has P1202 date, could this be 64 or 65?

Joe -- Your P1202 assembly date on a '010' maincase had to have been stamped on December 2nd 1965, for an early 1966 model year car. If it was for the 1967 model year, they started assembling those '010' maincase transmissions (probably) sometime in early August 1966, using the new assy. code dating system; ie. P7T02.

If a '64 or '65 model year maincase, those were definitely 3851325 maincases. From the start of '64 Muncie 4-speed production (say, Aug to late Dec of 1963 or early Jan '64), they had "Patent Pending" under the 325 part #.

Another visual identifier is the top bolt boss at the middle rear of the maincase. from about Nov / Dec 1964 325 maincases, depending on mould #, this boss became square on the forward end. Prior to that, on the '63-only '704' cases as well as all '64 and early '65 "325"s, this was rounded, just like the bolt boss on the bottom of the maincase.