The top of the engine next to the oil fill cap reads 395558 2 my 70 Supreme. Is there any definitive way to tell if this is 350cu / 310hp engine I think it is. Sure drives like it.
Also, the tag on the front of the engine block has has been removed. Is there another place the serial nos would be printed so if I can tell if this is a replacement or original engine? Starting to doubt it is.
Thanks in advance / any help or direction to publication is greatly appreciated. Al

 

That 395558 is the common 350 casting number....used for many years.

You say that "the tag on the front of the engine block has has been removed". Do you mean the VIN pad below the #1 cylinder ?

The last 6 digits of the number should be the last 6 digits of your VIN.

AFAIK, the only way to tell if your 350 was an original HC 4 bbl, would be documentation as all of the telltale items (pistons, orig intake, etc...) could have been replaced. IF you know its never been apart, you might be able to tell by looking at the piston tops. They should have a very shallow dish.

 

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Well, for starters the Olds 350 HC 310 Hp was STANDARD EQUIPMENT on the 70 Cutlass Supreme. So most likely if you still have the engine the car was born with - it's the real deal. Keep in mind they rated HP differently back in 1970, it was not measured as brake HP.

The tag on the front of the engine? There should only be a stamping pad that the factory would use to identify the engine to the car. Indy has given you a great pic of where to look. The pad actually faces slightly downwards, so you may need to clean it (NOT with sand paper) with degreasing solution to see the markings. It should start out 3(?)0XXXXXX The ? indicates the letter of the plant the car was built. The 0 is the 70 model year, and X's represent the VIN derivative.

Here's an actual picture of a 71 stamping pad so you get the idea.

 

So its a 350. Under the No.1 cylinder there is a stamped No.6. Does this correlate to any particular yr of manufacture? I can investigate the numbers matching aspect next time I am under the car. Thanks, Guys.

 

The #6 is the letter on your head. #6 heads are 1970 350 heads.

 

Ok, you're part way there. That is not a stamping, it's part of the head casting as Dave V V mentioned. Look down below it like in the pic, ok? The stamping pad is NOT all that easy to see because of it's downward angle. If the last 6 numbers on the stamping pad match the last 6 digits on your VIN? It's the original engine to the car.

Thx Dave, I should have mentioned that when I posted the pic; although I did say it was for a 71...I should not have assumed he knew what the casting meant.

 

Here is my engine stamping on my 350. It's a '76 engine, note the "6." The "3" at the begining has been messed up somehow but the picture shows the faint stampings you want to find. WD-40 on a rag will help clean off any gunk on it.



Adam

 

Allen,

I'm guessing he means the tape on the oil fill tube with the two letters that designate what the engine was. Most are long gone. I know they used them in 68, I assume they were still used in 70.

 

Close. It's always brake HP. What you're thinking of is net vs. gross HP. Prior to the 1971 model year, automakers used SAE gross HP, which was flywheel HP measured WITHOUT air cleaner, accessories, or stock exhaust manifolds. Starting with the 1971 model year this was changed to SAE net HP, which was still flywheel HP but with engines tested as installed in the car with accessories, air cleaner, etc. For the 1971 model year only, GM actually published both net and gross numbers, so you can see how much of the reduction was due to emissions and how much was just the difference in test method.

 

Mike, that makes sense. Those codes were used in 72 as well

Thanks Joe, yes that's what I meant. You have a way of making it soooo easy to understand.