What's the quickest way to tell if they are a 305, or 350 while the motor is still in the car?

In the old ones , I remember it had to do with what side the alternater was on.....

 

If you are 100% positive that the engine has not been changed from what the factory put in, the quickest way is to look at the 8th character of the VIN.

If you can't be 100% positive that the engine has not been changed from what the factory put in, get the block casting #.

You can look under the valve covers for the head casting #'s if you are 100% sure the shortblock and heads are paired the way the factory did them.

 

ya, I know about engine id. I just want to be able to pop the hood and tell if it's a 350 or 305.

Since these cars are getting older, and lots of them have been thrashed, the VIN tag ain't gonna help.

Kinda hard to get a look at those casting #s from above the car.

Just looking for a shortcut.

 

The casting number IS the shortcut. Hard to get much shorter of a cut than reading a number off the block and looking it up.

 

all right, so now I have the casting number - look it up?

Where?

On this site?

Will it break down into date code, etc?

 

There use to be ways of looking at one. Go by damper size, frezee plugs, alt., etc but being chevy parts can be swapped engine to engine so easy all that is BS.

Only way of knowing is by the block numbers. There's 2 sets of numbers

The sufix code. It's on the pad in front of the pass. side head. It will tell engine plant it was built at, mo. day, year, engine size (cid) what it was installed in, HP (not all will tell), carb it came with, trans installed behind it, etc

Then there's the block casting number. It's on the back, behind driver's side head, on the flange were the trans bolts up at. It will tell year range, size, and if its a 2 or 4 bolt main block.

To look up the codes. There's too good sites. www.mortec.com and www.nastyz28.com (on nastyz28 look on the left and click on numbers decoding)

Because I buy alot of engine cores to rebuild and sell, I printed out ALL the sufix and casting numbers, punched 3 holes in the side of the stacks and put them in a 3 ring binder that stays in my car.

Also you wanna look up the heads too. Just cause its a 76 350, or 64 327 dont mean the heads will always be. (Too easy to swapparts around)

Head casting numbers is on the head, under the valve covers, and inbetween 2 rocker studs. You can decode them on the same 2 sites

 

Thanks Night Rider! that was the answer I was looking for.

You're right, in the old days I would look at the balancer etc to give me quick clue. Thanks again.

 

Those old ways would still work; if you somehow knew that the motor was an entire assembly, untouched, just as it had been put into some car. Unfortunately there are very very few unmolested SBC motors left in the world. You have to identify each piece individually because they all mix and match so well, there's no telling what you could find. As an example, you might find a 63 327 block with an 80s 305 balancer and Vortec heads on it, which would all work fine, probably even run good; but to look at some one of those parts and assume that the engine was that engine.... would be erroneous to say the least.

 

92 Rag.. Your welcome. Glad I could help.

RB83L69.. Your right. Those ways would still work, just not something I would trust.

Like on my own engine....
I have a 71 350 block,
1965 327 heads,
69 327 damper,
aftermarket intake, valve covers, carb, etc.
1976 HEI dist,
1969 dz302 z28 PCV valve.
Late 70's to mid 80's alt. bracket/mounts,
1992 grand am alt.,
1991 ford turus elec fan,
1971 LT1 camaro fuel pump
1973 chevy truck 4 core rad.