how to tell 350 from 455 in 1970 olds

[mahoneybags21]

how can i tell if the cars got the 350 or the 455?

[mahoneybags21]

and is the 1970 350 a big block or only the 455 was a big block

[citcapp]

Here's a couple of ways (others will chime in with more)

Big Block 425 and 455

425 painted red ,455 painted blue, 350 painted gold

letter designation above the number one cylinder A or B or C or D or E or F or G or Ga etc.

number designation above the number one cylinder 5 or 7 etc

Thats for starters

[jensenracing77]

the 350 is a small block. the fastest way to tell a small from a big is to measure the intake manifold. the big block is 14 inches wide and the small block is 12 inches wide. small blocks are 260 330 350 and 403. the big block is 400 425 and 455.

[joe_padavano]

Originally Posted by citcapp

Here's a couple of ways (others will chime in with more)

Big Block 425 and 455

425 painted red ,455 painted blue, 350 painted gold

letter designation above the number one cylinder A or B or C or D or E or F or G or Ga etc.

number designation above the number one cylinder 5 or 7 etc

Thats for starters

Well, paint and cylinder heads can be changed. The only foolproof (and very easy) way to tell is to look at the block casting number. This is located on the small shelf above the water pump, where the oil fill tube goes into the block. Compare that number to these:

http://www.oldsmobilewiki.com/index.php/Category:Blocks

Also be aware that conventional terminology with Olds motors uses small block to refer to the short deck motors and big block to refer to the tall deck motors. Small blocks came in 260, 307, 330, 350, and 403 cu in displacements (including 260 and 350 diesel motors). The big blocks came in 400 (long and short stroke), 425, and 455 cu in displacements.

[jensenracing77]

thanks joe, i forgot the 307. oops

[mahoneybags21]

im goin to look at a 1970 delta 88 and the guy says it has the big block engine so the best way is too look at the casting number?

[mahoneybags21]

or does the vin number tell if the 455 would be in it?

[marcar1993]

Look next to the oil fill tube, if the # is "396021" then it is a 455.
This is where it will be (this is a torn down 68-76 350, location will be the same, also this is the casting # if it's a 350.)

[joe_padavano]

Originally Posted by mahoneybags21

or does the vin number tell if the 455 would be in it?

The engine code was not included in the VIN before the 1972 model year, so no.

[mahoneybags21]

kk the pic helped alot thanks