[street rodder 1937]

Hey Guys My son has a 1966 cuda with a 273.We are thinking about putting a early 318 in it. Will it fit? And bolt up. Somebody told me that the left side of the block by the frist two plugs there is a rounded out spot so the steering box will fit. Does the 318 have that also. Thanks Randy

[killerformula]

blocks are all the same. 273/318/340/360. I don't know about a round spot at the front, I've rebuilt a mopar before and didn't notice anything different about the front. Whatever this guy is talking about is not part of the block. If I were you, I'd dump a 360 in it, just a suggestion, but as long as your increasing cubes, why not go as far as you can?! 360's are great motors, and of course, the most powerful and best performing of the smallblock mopar motors.

Good luck, sounds like a great father-son project. Make sure to take pics for us at HR.

K

[30desoto]

streetrodder 1937

As killer formula said the blocks are all the same, no inditation in the old wide block that I know of and yes it will bolt up and work.
I myself think the old 318 wide blocks were good engines and have one in my 30 desoto, just depends on how much power you may need or want.
30dee

[poncho62]

When you are saying 318, you are not talking pre 68 are you?. Those wide blocks were different. After 68, the 318s were the same block as the 273, 340, 360.

They did change a bit in the water pump area in the early 80s, (I believe)

[DirtyJavelin]

The Poly (old) 318 is not like the other 318 engine. On 340 and 360 the left engine mount is different but not that big of a deal. The 318 and 340 have the same oil pan the 360's is a little different because of the end seal.
Unless your specific on a plan I personally would go with a 360. Even though the 340 is a little better then the 360 they are harder to find and more expensive.
But if you really want to use the 318 there is alot of things you can do with it all depending on what you want. It is a good engine just as any other Mopar engine.

[killerformula]

Originally posted by DirtyJavelin
The Poly (old) 318 is not like the other 318 engine. On 340 and 360 the left engine mount is different but not that big of a deal. The 318 and 340 have the same oil pan the 360's is a little different because of the end seal.
Unless your specific on a plan I personally would go with a 360. Even though the 340 is a little better then the 360 they are harder to find and more expensive.
But if you really want to use the 318 there is alot of things you can do with it all depending on what you want. It is a good engine just as any other Mopar engine.

common misnomer man. a 340 and 360 built with the same parts: the 360 would run circles around it. Only reason the motor got a bad rap and not much chance to perform the way it could have was because of the emissions era!

K

[DirtyJavelin]

340 engine has a 3.31 stroke the 360 has a 3.58 stroke.
If you find a T/A or have a R3 block they will have thicker main bearing support which you can machine for 4 bolt mains.

[killerformula]

Originally posted by DirtyJavelin
340 engine has a 3.31 stroke the 360 has a 3.58 stroke.
If you find a T/A or have a R3 block they will have thicker main bearing support which you can machine for 4 bolt mains.

.... ok, but the 360 will still always be faster.

K

[Goldduster360]

You might want to make sure the exhaust manifolds will bolt up to the poly engine too. Those engines are quite a bit heavier than an A-engine too. A-engines were designed with compact cars in mind that is why they were lighter. Your 273 with the right parts would probably be cheaper to build than the poly and would run circles around it.

I would still go with a 360