Engine designation

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Slappy

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Dont want to sound stupid but I need to know. What does LA, R/b ect. mean? I have all small blocks and I noticed when I was looking up parts it listed LA engine. How do I know what I have?
 
LA - 273, 318, 340, 360

B 361, 383, 400 except for odball 350 in the 50's

RB 413, 426 wedge, 440 except for oddball 383 RB in 50's

the B stands for B motor and RB stands for Raised B motor, it has a taller deck height.
 
While looking for parts keep in mind that the magnum blocks are different from the LA blocks and a lot of stuff won't interchange.
 
I do have a motor that I am not sure is a magnum. Is there an easy way to tell?
 
List them fishman, the non-interchangable parts.

Slappy, where are the motor mounts or is it a roller motor. (Some LA engines are a roller motors)
The numbers on the block would tell you after looking them up.
 
This Motor is currently in my Dart. It is apparently havng a head gasket issue. I am going to have to order new gaskets. This is when I saw the designations. I am going to get dressed and try to locate the numbers. Are the numbers on both sides of the block? Where can I look these up at? Would the gaskets be the same for a roller motor? Thanks Tod
 
OH! It's complete and running!?!?!

How many bolts on the valve cover?

5 = LA
10 = Magnum

intake bolts attach up and down = Magnum
intake bolts attach the intake to the head at head face angle or on an angle = LA
 
Heres a clear clean shot of a typical "LA"

100_1065.JPG
 
With that said I know it is not a magnum. Wow 10 bolts! Thats alot for a valve cover. How can I tell if it is a roller motor without looking inside? Tod
 
Pull out a pushrod. If it's short, it's a roller.

But your doing a head gasket, that will require you to pull the intake, unless your really good. Once you have the intake off, the valley will have a spider holding the roller lifters inplace.

You need to get "LA" gaskets because they have an extra hole for oil flow that the Magnum engines do not.
Intake to head gaskets also differ.
 
Thanks. I will post the repair once it is complete. This site is fantastic for help.
 
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