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GT 40P head conversion

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shierh View Drop Down
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    Posted: February-20-2019 at 5:57pm
Im still considering the change. My engine is stock other than 30 over from rebuild. Stock pistons etc.
Engine is basic 1980's 351w.

Im not changing anything but heads at this time.   Any issues?
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phatsat67 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote phatsat67 Quote  Post ReplyReply Direct Link To This Post Posted: February-20-2019 at 5:59pm
No issues, you will just be leaving some power on the table if you don't swap an intake.

Heads need to be drilled to 351 size bolts if they haven't already. Most likely should measure lifter preload as it could change some swapping head styles.
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rosconole View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rosconole Quote  Post ReplyReply Direct Link To This Post Posted: February-20-2019 at 6:59pm
Yes Performer intake some roller rockers would be nice. alot of times people selling heads and rockers together if you look around. Also always need to check pushrod length.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Orlando76 Quote  Post ReplyReply Direct Link To This Post Posted: February-20-2019 at 7:00pm
I used Clearwater Cylinder. Think they got them sent to the Tangerine Estate the next day, already drilled and waved the core charge because he knew my GT40’s were most likely cracked plus the marine use.
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shierh View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote shierh Quote  Post ReplyReply Direct Link To This Post Posted: February-21-2019 at 2:22pm
Will do intake at a later date.
Why would push rods be an issue?
Shop is already aware of the bolt hole size so should be fine.
Lifter pre load? isnt that for gm engines? (0 lash then 3/4 turn beyond)
Believe ford is torque it down and that's it.   
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Gary S View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Gary S Quote  Post ReplyReply Direct Link To This Post Posted: February-21-2019 at 2:33pm
Pushrods should not be an issue but no one should bolt up an engine without checking any and all clearances. If block has been decked or heads cut, clearances over original will be changed. Lifter preload applies to all hydraulic push rod engines.
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halfnelly View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote halfnelly Quote  Post ReplyReply Direct Link To This Post Posted: February-21-2019 at 2:47pm
On pedestal mount non-adjustable rockers, the preload is adjusted with shims:

https://www.summitracing.com/parts/fms-m-6529-a302
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rosconole Quote  Post ReplyReply Direct Link To This Post Posted: March-03-2019 at 6:46pm
I just bought another set of GT40 3 bar heads ;)
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