Author Topic: 302 heads  (Read 8891 times)

bob69

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302 heads
« on: December 22, 2005, 04:55:32 PM »
the heads on my motor ( 302 ) are in bad shape a couple of cracks on each one, the shop says there to far gone, I can get a set of 482s double hump heads and put 202 valves in them. my ? is since there not orginal is there a better way to go. Thanks Bob

JohnZ

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Re: 302 heads
« Reply #1 on: December 22, 2005, 05:49:51 PM »
482 heads came with 1.72/1.5 valves and small ports and it would be a waste to put bigger valves in them due to the port restrictions. 462 heads came with both 1.94/1.5 and 2.02/1.6 valves (just as 186's did), but if you take a 462 or 186 head with 1.94's and open them up to take 2.02's and don't also make the unshrouding cut in the chamber wall adjacent to the intake valve, they'll flow less than they did with the 1.94's. Photo below of the factory unshrouding cut with factory 2.02 valves.

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bob69

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Re: 302 heads
« Reply #2 on: January 08, 2006, 04:47:51 AM »
John i was at the shop the other day and took a look at the 482 heads, and put my 202 valves in them and they fit nice and high.( I doin't think they ever had a valve job ) I then checked the port size with water it came to 174. Is it possable that these are stock 202 heads. Or is there a way to fool me. Thanks Bob

JohnZ

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Re: 302 heads
« Reply #3 on: January 08, 2006, 08:19:38 PM »
None of my references show a production application for 3714482 heads, which leads me to believe they're service-only castings; all I show on them is '62-'67 327 usage with 1.72" intakes and 1.5" exhausts with no bolt holes, and those early heads with small valves usually had the small ports as well.
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bob69

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Re: 302 heads
« Reply #4 on: January 08, 2006, 11:34:31 PM »
Thanks John , I know they have the bolt holes and think the date code is 67. I'm starting to think that I might have miss read 482 for 462  Thanks Bob