Questions for new Cutlass Owner

a caddy 425 had 9 bolt valve covers

He's taking about an olds 425. Block numbers are between oil fill neck & intake

The Heads will also have a letter in front of #1 and behind #8. These engines are 40+ years old, who knows what has been done. Some people have converted the 425 to a 455. The 425 has a forged crank and a different looking balancer. Some 425's had a different 45 degree cam bank angle, some the same as 68 and up 39 degree cam bank angle. Pretty sure all 425 had larger .921" lifters with the 39 degree cba, .842" lifters with the 45 cba.

Evan's 85 said:

He's taking about an olds 425. Block numbers are between oil fill neck & intake

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he just mentioned it was advertised a 425 and didn't mention what brand so knowing how to identify the caddy 425 I threw that out there

If it's a 455, the numbers on the block will read 396021F between the water pump and intake.

You could have a 455 block with 425 guts.

Remove spark plug #1 and use a long rod to measure the distance the piston is in the hole when at BDC and TDC.
425 will be 3.975", 455 is 4.25"