Thread: 305 and 350's

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Goodmorning! Noticed there are alot of pretty smart people here. Just wanted to ask a question that is probably older than the hills.What is the best way to tell the difference between a 305 and 350 Chev small block? I have heard many different slants on this and looking for the truth. I've heard to look at the timing chain cover etc. but still kind of confused. Can anyone help? Thanks.

I usually look for the position of timing pointer as it related to the ballancer... The 305 will be at the 12 o'clock position while the 350's marker will be around the 2 o'clock position if you were looking directly at the front of the engine...

Hope that helps...

Dave Brisco

Thanks Dave. I heard of this but wasn't sure. This is my first time on this site...I just found it... I'm sure I'll be back for more reading and maybe even a question or two. Thanks again.

serco... Glad to have you here... Check back often and ask all the questions you like... We are always happy to help if we can...

Dave Brisco

Thanks, Streets. Any info I can get is better than none at all. This is all great stuff. Thanks.

There are countless things you can look at that "might" tell you what a block was. But with the hundreds of variations that were produced- Not to mention the years and years where people worked on them and replaced things(usually wront) - Its almost impossible to visually glance at a block and know what it is.

The only 100% correct way, that works everytime, to determine what a block is- is to write down & Look up the casting numbers

http://www.mortec.com <--has all the decoding stuff for SB & BB chevy blocks & heads. There are also several books available that list these casting numbers, i prefer mortecs site because i'm a cheapskate.

SB chevy block Casting numbers will be visible on a little shelf at the back of the drivers side of the block - You will probably have to clean some crud off to read it if it is installed in a car-

There are also application numbers & code stamped onto a small pad on the front of the engine on the passenger side- right below the head. You may have to move the alternator to read that one- If the block has been rebuilt, this pad could have been machined smooth, and the stampings may no longer be visible.

When you look at those numbers, there may be several years and displacements that use a given casting number. That is where the front pad's code comes in- that will give you the application as well as the block type- Try to get both numbers and that should tell you for sure what the block is and what it came out of.

-Ben

Ben. Just got home from a trip into the States. Thanks for the information. I will use it wisely. Thanks again.