Help with Olds 307 Project

Olds 307 and 403

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Oct 4, 2018
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Melville, Saskatchewan
What cfm is the Holley carb? It will probably be way rich as is and the square to spread bore adapter as mentioned. He will need stock replacement pushrods for a 85 to 90 Olds 307 Vin Y. They are different as that motor has the taller roller lifters. Surprised a flat tappet doesn't go flat using the roller lifters.
 

yitzac1990

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Oct 21, 2020
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Huntsville, AL
i have no idea what the CFM of the carb is...

I believe the push rods that i had help finding were about 7.7" long....does this sound right?
 

Olds 307 and 403

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Oct 4, 2018
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Melville, Saskatchewan
Distributor should work fine, be aggressive with the timing. A 600 cfm is plenty big for that 307. The push rods sound right. My regular, no roller cam push rods are just over 8" long. I believe there is about a 1/2" difference between the two.
 

Olds 307 and 403

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Oct 4, 2018
996
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Melville, Saskatchewan
What about the 58070 part number? They seem to be the same, just un-coated...
Yes. Quite often there is something like -1 added to the part number for ceramic, this has an actual different part number.
 

yitzac1990

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Oct 21, 2020
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Huntsville, AL

Olds 307 and 403

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Oct 4, 2018
996
265
63
Melville, Saskatchewan
Yes, that Mr Gasket adapter will work.
 
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