Hi everyone, I just bought a 72 Challenger that came with a /6 out of the factory and I am trying to find out how to tell if the cars engine is the original.

I have the casting number which is 2806830-3, I am trying to find the vin or engine stamp on the engine but am having trouble trying to find it. I have looked on the internet and am still having problems. I am really new when it comes to knowing locations of stuff on the engine. So if you can help please explain in lament terms. Thanks again. Look forward to the info.

On a slant six you should have a pad of metal below the #1 spark plug where the cylinder head meets the block (the pad is actually an extension of the block deck...it will have some information pertinent to your engine (note if the lock was rebuilt in the past and heavily decked the pad will be blank).

Also near the back of the engine on the passenger side near the pan rail there will be another pad (may need to get some rags and brake clean to read it), this should have the last numbers of the Car's VIN that the engine was assigned).

Good luck on the acquisition ( 1 of 842 6 cylinder production cars in 1972).

-D.Idiot

Thanks for the reply I look around the number 1 spark plug and couldnt find the number, also is there a picture of where the location you are talking about the vin number location on the engine. I am really trying to look but i feel like i am looking in the wrong spot and not seeing it on the passenger back side of the engine. I guess I am more of a visual learner.

Here is the pad below the #1 spark plug hole to ID the engine (this one is from a 1972 John Deere Tractor)...you may need a brush to remove the smutz to read it.

-D.Idiot

Great that helps a lot. So i have to unbolt the top right? Sorry really new to this. I also found a number a few inches right side of the casting number. Number is 04116 u if I remember correctly. What does this number mean?

Other views of the same, should be visible somewhere behind the alternator bracket below the first plug:



Look here for numbers like D.I. shows above, they are exposed with engine still assembled (except as mentioned if deck was milled a lot):

_________________
1966 Coronet Deluxe

_________________
1966 Coronet Deluxe

Found the number. So is this the number that should match my vin number? If so I guess it is not the original unfortunatly. Oh well I will probably keep the slant 6 in since it is kind of rare for an ebody to have one. Kind of cool to me.

Can anyone tell me what the letters mean?

No, spray some cleaner just below the head gasket to the left of the blue oil filter as you are facing the passenger side of the block. The late blocks (70-'s-80's) are marked here.

Good luck,

-D.Idiot

Thanks, I lifted the car and couldn't find any number anywhere around there from underneath. Is there a pic or something that could show location. I know the few on here shows the other one.

hi, does the flat pad below # 6 cylinder have any numbers on it? from your pics it looks about 1.5" x 1.5" and right below # 6 . ron

I found the flat spot and it was blank. Does this make sense? I figured it would have some sort of number on it.

Anybody?

A 71 Challenger should have a "5 freeze plug" block with casting number 2806830-XX on the driver's side.



The gussit behind the water pump will taper, getting bigger at the block.



Basically, these are 68 thru 76 forged crank SL6 blocks.

As most know, all the auto manufacturers started stamping partial VIN numbers onto engines and transmission cases, in the late 1960s (1969 model year) so your engine & trans shauld carry part of the vehicle's VIN number.

For a SL6, that would be on the side of a casting boss, along the lifter gallery, (passenger side) near the rear of the engine block. You will need a mirror to see it when the engine is in the car.
DD

http://www.slantsix.org/articles/dutra- ... blocks.htm