question is the 53 chevy 6 cylinder 235 and 55-59 chevy V8 265-283 automatic transmission adapter the same?
If you're talking about the cast iron piece that goes between the block and transmission, the answer is no. Totally different bolt patterns on the blocks.
I’m no expert, it’s been a long time since I messed with a Chevy 6 but I’m pretty sure that with the early Powerglide, the transmission is pretty much the same but the “adapter plate” is different. It’s a cast iron plate that bolts to the block and the trans bolts to that plate.
They have different engine plates but only the early cast iron powerglides will bolt up. A newer, 62 327 aluminum PG or most all 63-up transmissions will need an engine plate like one from Buffalo Enterprises in Oregon to put a more modern transmission to your 1953 6 cylinder. If going to an automatic a re-drilled starter ring gear flex plate will also be needed.
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