DAVID SLUDER

I have been looking to purchase a 1969 vert, how can you tell if its a factory Big block or not, is there a number stamped on the car?

BBCorv70

Engine codes weren't included in the VIN until 1972.

First check would be the partial VIN on the stamp pad, should match the car. A tank sheet if available would list the big block as an installed option. Other clues are the tachometer, redline is different for big block, caps instead of U bolts fastening the half shafts to the differential. Rear sway bar, larger radiator, and a big block hood. The tank sheet and/or an original invoice, maybe a POP, are the best indicators of authenticity.

Easy Mike

Original factory documentation with the car. Ask the seller what type of documentation is with the car. Look over the paperwork when you see the car.

Since the big block was an options package, any or all of the package could have been installed by a previous owner.

joewill

in the absence of any documentation, there is no way to confirm. even with documentation, it could be faked. there are about 30 characteristics that differentiate small block cars and big block cars, all can be purchased in the after market.
the more of these 30 you have, then the more faith I would have that the car is what the owner thinks it is.

there is high motivation to fake 69 big block cars, and a good percentage of them are faked.

unless you are really into the numbers game and know what you are doing, then the best advice is to buy the best condition car car for the money and save the numbers game for your next car.

I played the numbers game in ignorance years ago and it caused me grief. Since then I have decided not to play the numbers game even though I know the game much much greater.

DAVID SLUDER

Wow what great information, thanks everybody for the input so far, I have found numerous cars that I like but have a small blocks in them, NOM is not an issue to me so maybe I can buy the car I like and install A BIGBLOCK.

Faster Rat

You got it! Another infamous fork in the road...do I take the "original" path or do I take the "modified" path. I just wish I had the money to do both, because they are equally valid. Just a question of money.

C6DuffMan

Some other items were a rear sway bar and heavy duty caps on the half shafts U joints, not U straps. Of course, these could be swapped in as well.

7T1vette

If you are not paying a premium price for a "guaranteed, numbers matching, completely factory-built and fully documented all-original car", who cares if it is factory installed or not. Just make sure the installation is done well and that it operates and performs as it should.