Hello, I am a new member of the forum. I am hoping someone can help me with a burning question about my 1966 Mustang 3-speed, 6-cylinder coupe.

I have visited many sites about build codes. According to these decoders, the engine block and intake manifold in my car appear to be 5 or 6 months newer than the VIN and bill of sale (which I have from the prior owner). Or maybe I am reading the codes wrong?

The car was sold in March 1966. Based on decoder websites I have visited...

1. The fenders were likely made in February 1966. ("2 15 2" and "2 8 3")
2. The steering box was possibly made in January 1966. ("6A25B")

However...

1. The intake manifold shows a code of "6H16". (Is this August '66?)
2. The engine block has two codes. "6G25" (July '66?) and "6J30V" (Sept. '66?). The engine is a 6-cylinder, 200 cid, which matches the VIN. (In other words, this type engine belongs in this car.)

Under the hood the entire car appears to be the same general age, same wear, etc. Could there have been a major problem very early in this car's life (maybe even after just a few months) which required replacing the engine?

I am trying to determine if I have the original engine. Thank you in advance for your help!

 

it is not the original engine.

 

Are you certain? Is there anywhere else I could check to be absolutely sure?

I am wondering if maybe the previous owner blew up the engine less than a year after she owned it and got the whole engine replaced under warranty. That seems unusual.

 

yes . . you can not have an original engine if the engine was built 5 months after the car was sold.


no.


unlikely but possible, but if that is the case, the engine would not be original to the car.
.