I'm trying to determine if my car has matching numbers. I own a 1965 Olds Dynamic 88 convertable. Can anyone suggest where I research this subject? A bit confused by what I have seen so far. I noticed a section in Year One's Cutlass catalog, but not sure it applies to Dynamic 88s. Not only would I like to determine how to match the numbers, but I need info on where to look for the numbers on the engine / trans / other parts. Thanks. Larry

First, "matching numbers" is the most mis-used term in the collector car hobby (with the possible exception of "classic"). Starting in 1968, the Feds required a VIN-derivative to be stamped on the engine block and transmission. For Oldsmobile this VIN-derivative was nine characters long and comprised of the first character and last eight characters of the car's VIN. If these numbers match each other and the VIN, then you can be assured that the car has the original engine and trans and this is "numbers matching" (or that the block and trans have been restamped, which is a different problem). Your 65 predates these "VIN-derivatives", so there really aren't any numbers to match.

Having said that, there are other, less definitive things like casting numbers and date codes. A certain year and configuration automobile should have specific parts, so these casting numbers must be correct for that factory build configuration. In addition, major items (block, heads, manifolds) will have cast-in date codes, which should predate the build date of the car by one to three months. As I said, these are not definitive since Olds built thousands of cars in that one to three month period. Having a date code or casting code that is clearly incorrect is proof that the part is not original, but just because it is in the correct range doesn't prove it's original. Finally, on the pre-1968 cars Olds stamped an engine unit number on the front of one of the heads. This number does not match the VIN, but certain characters in the number can provide additional (but again non-definitive) proof of originality. For example, the 65-67 442s carried engine numbers that started with the letter "V". A 442 of that vintage without one of these engine numbers clearly doesn't have the original engine.

Whenever I see a pre-68 Olds that is advertised as "numbers matching", I immediately ask the seller to please point out the numbers that "match". Of course, there aren't any.

Joe,
Great explanation. I have a few numbers from the engine. Maybe you can tell me what they mean? There is a casting stamp on the block with the number 386525A. There is also a 4993 nunber stamped int a machined surface area of the block. One head has the number M064184L stamped on it. Is there anything you can teach me about these numbers? Thanks.

I would like to add slightly to Joe's excellent answer.

First, I would like to suggest that the most overused term in our hobby is "rare"; followed by "classic" and "numbers-matching".

But as to there being no numbers to match prior to 1968, I must respectfully disagree. As Joe points out, a vehicle is produced with certain parts, many of which carry either a casting number or a date code or both. And while, again as pointed out by Joe, it is impossible to prove that a specific part is ORIGINAL to a vehicle; it may be proved that a part is CORRECT as far as production for that vehicle.

Many judging authorities and enthusiasts feel that matching for correctness is important; and some judging authorities feel sufficiently strongly that they publish lists of the various casting numbers, and a suggested date "window".

Many of these judging authorities have "original" classes and "modified" classes. Too many non-matching numbers will cause the vehicle to be judged in the modified classes.

Jon.

Taking the above 1 step further for your specific vehicle:

In 1965 Oldsmobile used 9 DIFFERENT 4-barrel carburetors and 11 different 2-barrel carburetors.

Just looking at the 4-barrel carburetors, the best commercial rebuilders "group" the 9 different 4 barrel carbs into only 2 groups. These they build to their own specification (which is never the same as any original specification). Some of the less expensive commercial rebuilders have only 2 groups of 4-barrels from 1959 to 1965!!! Will a 1959 carburetor work on your 1965? Probably. Will it work as well as a properly calibrated original as calibrated by Rochester to Oldsmobile's specifications? NO WAY. As the commercial rebuilders are aware of this, the identification tags are removed from the carburetors. This is one of the reasons why some of the auto parts store parts are less expensive than if one visits the original factory dealer.

So to summerize, your 1965 would have a carburetor identified by a tag, with a calibration specific to the original engine, transmission, and whether or not the car was equiped with air conditioning. This number is published, and your carburetor is either "numbers matching" or it is incorrect.

How important correctness is would be a decision of the individual.

The same can be said for engine blocks, heads, distributors, generator/alternators, transmissions, differentials, etc., etc., etc.

Jon.

To add more to this topic. Joe is correct about "matching numbers" - I'd also like to add the word "original" to our list of overused words.

On a more serious note, while pre-68 cars do not have a specific matching number, the engine code stamped with the "engine number" can, at least, tell you if the engine was the right one for the car. The Chassis Service Manual usually indicates what this code might be. For example in '65 the codes are:

33400, 33600. 33800 = T
35200 = U
35400 - 38600 = "M" for 2 bbl; "N" for 4 bbl.

Transmissions have a usage code tag attached which does give a manufacturing date, in some cases, and always the usage code. Same for the rear end.

You can contact me off line @ bob.gerometta@wildaboutcars.com and I will provide you with scans of the appropriate pages from the 1965 Chassis Service Manual.

The Chassis Service Manual can be acquired in CD format from Gearhead Cafe - www.gearheadcafe.com.

Bob

"THANKS for saying that" --- First, "matching numbers" is the most mis-used term in the collector car hobby (with the possible exception of "classic").

Have you tried sending your info to the GM Heritage Center.
(gmhc@gm.com) Another thing you might wan't to check out is a web site I found for my 1962 Super 88, I know it's not the year of your car but it has helpful info and site's.
(http://home.comcast.net/~oldsfan/MySite/62oldspage.html)

Luckily my car had come with the Protect-O-Plate witch has helped me know for a fact my car is origanal and has what it came with. So I hope this info can help you.

Hello everyone. This thread was of particular interest and especially timely for me. As a quick background, I have a 64 Buick Riviera (ROA 11550), a 61 Chevrolet Impala 2-dr, and a 66 Ford Thunderbird convertible in various states of restoration. Deciding I wasn't busy enough, I began looking for a 66 Olds Tornado, found a project/fixer upper on ebay, submitted a low ball bid and wound up winning the thing.

The vehicle is presently in Oklahoma City, and coincidently I happened to be there for work this past Thursday and Friday. The plan is to have a local shop get it roadworthy and then return to OKC and drive it to Denver next weekend to put in storage. (I guess part of the adventure was picturing my buddy and me roaring down Oklahoma interstates in a primer colored Toro ala "Fear & Loathing in Oklahoma City")

But I digress. When I looked under the hood yesterday as part of a quick inspection (I had a flight to catch), I began to have doubts about whether that engine belonged to that car. I have a 66 Olds Shop Manual at home, but couldn't remember where or what to look for to verify the engine correctness. I found a few numbers cast into the intake manifold, heads, etc, but the one number I did find and record "389244" was located on the block just above the water pump.

So, until I have a chance to access my shop manuals, any additional info on 1966 Olds Toronado engine codes (so I can tell the shop where to look to help determine correctness) would be appreciated.

thanks in advance
alex bonino

I've answered my own question. A little internet research revealed the following:

"389244" is the engine block code for 66-67 Olds 425 ci engine

Engine block casting number is found at the front of the engine, on the horizontal ledge just above the water pump (which by luck is where I happened to look)

Determined this info at the olds 442 website, which has a wealth of Olds casting number decode info (beyond just the 442) and has not been mentioned yet in this thread:

http://www.442.com/oldsfaq/ofblk.htm#Blocks

hope this info helps others
alex bonino

While your were successful, don't believe everything at that FAQ. That FAQ is simply a compendium of posts from the old Oldsmobile email list server from 10-15 years ago. Some of it is correct, some is not. It has the same problems as Wikipedia, but with less vetting... and I even wrote some of it.