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Discussion Starter #1 (Edited)
Came across some E7's from a 95 GT and wondering if they can be bolted onto a 351W? Reason i'm asking is cause I need one of my heads replaced....
i know whats required, as far as the 351 using 1/2 size bolts while 302 use a different size but i'm more concerned about if I would lose power or worse...
 

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i believe the valves are bigger on the 351 heads. i think it depends on the year though.
 

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Contributing Sr Motorhead
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E7TEs have 64 cc chambers, and 1.78/1.46 valves. They were the best flowing factory SBF casting until the advent of the GT40 and GT40Ps. The E7s were used on 5.0 HO GT Mustnags from 87-95, and we know that those were no slouches! E7TEs were also used on pickup/van 5.8L motors from 87-97. Lots of those in junkyards now, and they would already have the bigger headbolt holes.

GT40s were used on 93-95 5.0 Cobras, as well as 1st gen Lighting 5.8L (correct bolt holes again :) ) and 96-97 Explorer 5.0s. Late 97-2000 5.0 Explorers got GT40Ps with their revised sparkplug location and angle. GT40Ps have smaller 58cc chambers. Valve sizing for GT40s are 1.84/1.54. Valve sizing for Ps are 1.84/1.46, but the Ps flow better than the standard GT40s due to port shape.
 

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Discussion Starter #5
ok but can i bolt these up to my 69 351w stock 2v without any other issues? like not having to change the pistons, will it hold up with the 2bbl carb meanwhile? etc...
 

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I am not sure that you can use stock cast iron exhaust manifolds with the modern cylinder heads. It has to do with the angled spark plugs.
 

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E7s will bolt right on once you enlarge the bolt holes. as for compression, since I don't know from your post what year your 351W is, I can't say for sure. '69s (C9OE-B,D) have 60cc chambers, 70-up castings have 69cc chambers. So putting a pair of E7s will lower the compression of a '69 a bit, and will slightly increase compression on a 70-newer.

E7s would also be a good choice with modern unleaded gasolines since the valve seats are hardened. E7s are set up for pedestal rocker arms.

As for exhaust manifolds, anything but the GT40P heads have standard sparkplug location and angle.
 

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Discussion Starter #8
my 351W is a 69 block (69 Cougar)

would there be a significant loss of power since the compression ratio is lowered in my 69? would there be an issue with the valve from the E7's to the 69 351W?
 
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