So is there any way to tell if an engine has been replaced if the block is from the proper year? How much does it matter if it's been replaced as long as the block is from the proper year?
Some people are full blown anal retentive purists and "original" means everything.
For others, a small block Chevy would be the propellant of choice. I think most
T guys would prefer an original engine, but "close enough" will suffice and getting
out and driving is most important.
If the engine number does not match the title then it has been replaced or it has the wrong title. (or other paper work required by your state) If your block has a cast date, and that date is after the title date, it's been replaced. If the car is pre starter/generator and it is a later block, it's been replaced. If your car is before introduction of the 26/27 engine and it has a 26/27 block it's been replaced. If it's a 26/27 car and the engine number does not match the number on the frame, it's been replaced. etc
As long as numbers match the paper work, some will not care, some will not care even if the numbers don't match till they try to get a title for it out of state.
So if you have an '18 coupe and a block with a number corresponding to an '18 production date, the only way to tell if it is original or not is by paperwork, which can be changed?
But sometimes there were running changes during the model year, so some cars, especially during certain years, can be pinpointed as being made early or late in the model year. For them it would be preferable to have an engine within some certain months - if you're into car show judging as MTFCI does.
Look in McCalleys book. It has day by day engine numbers. If you block doesn't match the information for the year of your car, then it the wrong engine, and even if it for the correct year, there is no guarantee it's the block that came with the car originally.
Another way (if you have it) is the body number. Mine has a 1920 date body number and a 1920 engine but title does not match engine number... soooo
The rules state all changes made by anyone at any time under any
circumstances will be documented using Form B129-a of the Uniform
Code and placed in the permanent vehicle file.
Clearly, the answer here is to check the permanent vehicle file. Duh !
You can't always tell by the engine number either. It has been the practice for some to grind off the number and stamp in the number on the title. Other after market blocks came with no number and the original number was stamped on them. Look for other signs such as casting numbers etc.
It all boils down to how 'pure' you want to be. I'm not a show guy so an engine that fell into the 1920 T range if I was building another 1920 T or replacing an engine in a complete 1920 Touring would be OK for me.
There are endless variables on what makes a 'pure' T so I'll let those guys chase that rabbit which they probably will never catch. Good luck.
I have never seen a body number list. The body number by 1920 does not tell you any thing more then how many of that body was built by the Co that made the body and there were several Co making bodies. If there is a body number list please where can it be found?
Here is the info on body numbers and dates for the Beaudett bodied Ts:
I do not see a list, some subjective information inferring the the "B" bodies might fall into a range and where to look for the body numbers. I am not saying you do not have a 1920 body, just do not see the information in that or other links provide as to where a number might fall into a given range for a given year.
Engine blocks actually changed quite a lot over the years. The only variation during car production that lasted more than two years, was the late 1922 through '25 block. Most changes had a cross-over time of several months that both the earlier and later variation would be used. The casting molds would generally be used until they wore out or broke, but changes would be made in the mold patterns.
I don't know all the changes off the top of my head, and have never seen a good reference listing more than a few of them.
Early blocks, changed a lot! From 1908 until mid 1912, the location of the serial number changed at least three times. The first 2500 engine blocks were so completely different that they cannot even be really considered to be the same engine. Before 1911, the main bearings were done differently, the strength, reinforcement, and thickness of the bearing webs are different. Several pattern markings, numbers and vent locations are all different. There are even a remnant or two of the earlier blocks still showing.
By mid 1912, the serial number location was set, and most other major layouts were similar to what would follow. Early engines were open valve, no covers, no chambers. By the end of 1911, the valve springs were enclosed in two small chambers by two small covers.
Mid '13, the rear of the block had the water jacket enlarged, eliminating a step at the back of the block. By late '13, the two indexing blocks inside the crankcase were made smaller, square instead of rounded. I have seen several late '13 blocks that had one of each earlier and later indexing blocks inside. At about the same time, the so-called "freeze plugs" were changed from threaded to pressed in style. All through those years, the location and size of the casting dates also changed a few times (casting dates were used to track casting problems in the factory).
Late in 1915, the serial number embossment was enlarged to accommodate the million or more size number. Something I find interesting here, is that I have seen several large number pads with 9XX,XXX numbers on them, and more than a few earlier small pads with million plus numbers that appear to be factory. The change was made, but both patterns used for several months.
Later, in 1916, the shape of the number pad changed again. The '17s number pad is quite different than the earlier '16s. In 1918, the casting date method changed from in line, multiple changeable dies, to a single circle with a date code.
The next big change, was for the generator added early in 1919. The entire right front corner of the block had to be altered to accommodate the upgrade.
Late (I think?) in 1921, a move was made to alter the valve chamber from two small ones, into a single large chamber (cheaper to manufacture). The crossover during which both earlier two chamber and later single chamber were both used was unusually long. I wish I had taken taken notes on this over the years. I believe I have seen very late '21s with the later style, and early '23s with the earlier two chambers. In this same time frame, the Ford script was eliminated on the outside of the crankcase, and casting dates were also dropped. I don't know just when, but there was yet another change in the shape of the serial number boss (must have changed that thing eight times in ten years!).
For about three years, now, the block didn't change a lot. Then late in calendar '25, for the '26 models, the back of the block got an obvious change in order to attach the hogshead to the rear of the block, and improve the rigidity of the engine. Model T production use of this variant was less than two years (until the end of model T production in June of '27). However, after production blocks continued to be manufactured as replacements until 1941. I don't know when the last one was cast? It could have been a few years earlier. But they probably continued using the molds and patterns from years earlier, making them the longest running unchanged engine blocks for the model T!
And, for whatever it is worth? My 1919 Boat-tail has a '25 engine block. And I don't care.
Drive carefully, and enjoy, W2