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Discussion Starter #1
I've got a '65 got that i don't know much about it's motor life or work done on it. It's a 389 with head code 092 and 3x2 intake #9778818 . From what I've found on the interweb so far is that the intake is for a '65 and the heads most likely for a '66. Is this combo ok a far as port matching etc.? While i'm at it, the engine has tall aftermarket valve covers on it, and the originals were included and both show indentation rocker "hits" at the top inside the cover. Don't know for sure but I don't think it has roller rockers. I assume that's why the tall covers were put on but I would like to go back original. It's been suggested to use thicker gaskets which may be a cure, but I'd like to know the cause if possible. The inside of the valve cover pic shows the dents. Any and all input on both Q's would be welcome. Thanks. P.S. Where does the stock ignition coil mount?? Mine is just kinda not in an original location I'm sure.
 

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I've got a '65 got that i don't know much about it's motor life or work done on it. It's a 389 with head code 092 and 3x2 intake #9778818 . From what I've found on the interweb so far is that the intake is for a '65 and the heads most likely for a '66. Is this combo ok a far as port matching etc.? While i'm at it, the engine has tall aftermarket valve covers on it, and the originals were included and both show indentation rocker "hits" at the top inside the cover. Don't know for sure but I don't think it has roller rockers. I assume that's why the tall covers were put on but I would like to go back original. It's been suggested to use thicker gaskets which may be a cure, but I'd like to know the cause if possible. The inside of the valve cover pic shows the dents. Any and all input on both Q's would be welcome. Thanks. P.S. Where does the stock ignition coil mount?? Mine is just kinda not in an original location I'm sure.

Intake ports are all the same design from 1965 and up. If in doubt, quick way to ID is the front 2 intake bolt holes. The '64 and earlier are diagonal. Later tripower/heads are opposite. See pics.

Rockers hitting the valve cover - Roller rocker design, much thicker profile. And, higher lift cam may have been installed to aggrevate the problem. They make valve cover spacers that would be the solution versus thicker gaskets which may not be tall enough for what you need. They come in different heights. https://www.medicemfg.com/products_get.php?c=Valve Cover Spacers - Pontiac

Coil appears to be attached to the back of the passenger side head. See photo.
 

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PontiacJim. Thanks for your reply. Guess i'll have to crack it open and see what the valve train is, but if stock, color me puzzled as to why the dinging occurred to begin with. I think i have the right manifold-head set up based on the #'s and photos. The coil thing is creating an issue. I see now where the bracket would bolt to the back of the passenger head. I bought what was touted as the correct bracket for '64-'67, which I now find is not correct for a '65 (and probably a '64). The curvature is too small to surround the coil and then bolt as designed. Why it would be proper for a '66-'67 is unclear to me. Surely the coils used for those years are the same size as previous ones. I now see that there is a used one with coil that states it is specific for a '65, but don't want to pay almost $50 for a bracket. Where there's a will there's a way. Bracket modification is the next step. Thanks again!
 

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PontiacJim. Thanks for your reply. Guess i'll have to crack it open and see what the valve train is, but if stock, color me puzzled as to why the dinging occurred to begin with. I think i have the right manifold-head set up based on the #'s and photos. The coil thing is creating an issue. I see now where the bracket would bolt to the back of the passenger head. I bought what was touted as the correct bracket for '64-'67, which I now find is not correct for a '65 (and probably a '64). The curvature is too small to surround the coil and then bolt as designed. Why it would be proper for a '66-'67 is unclear to me. Surely the coils used for those years are the same size as previous ones. I now see that there is a used one with coil that states it is specific for a '65, but don't want to pay almost $50 for a bracket. Where there's a will there's a way. Bracket modification is the next step. Thanks again!

Not sure if yours is this type, but doesn't it have a long machine screw with nut on the end? Coils are all basically the same. It's either a poor repop or you might see if you can get a longer machine screw, or even possibly use a longer piece of threaded rod cut to size and nut each end.

If your rockers are stock, then someone may have at some point installed roller rockers. Damage was done once it was fired up. That's why people opt for the taller valve covers.
 

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Discussion Starter #5
About the coil bracket. Having to bolt the bracket to the back of the head without the coil squeezes it to a point that the coil won't fit in when bolted. Tried to bolt it on with the coil installed appears to be near impossible as the two ends aren't compressed together and trying to push them together with a bolt that won't bottom out and get it started while trying to hold on to the entire assembly while hanging upside down like a bat at the back of the head is challenging to say the least. But again, thanks for all your input!
 

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About the coil bracket. Having to bolt the bracket to the back of the head without the coil squeezes it to a point that the coil won't fit in when bolted. Tried to bolt it on with the coil installed appears to be near impossible as the two ends aren't compressed together and trying to push them together with a bolt that won't bottom out and get it started while trying to hold on to the entire assembly while hanging upside down like a bat at the back of the head is challenging to say the least. But again, thanks for all your input!

OK, I see. Sometimes I use a nut/bolt to draw the 2 together and you might be able to then use a pair of vice grips to "contour" the bracket around the coil. Ship it to me and I'll get it to work - BFH, Torches, Welder, .........LOL. Just keep working at it.
 

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The 092 heads are 1966 'Big Car' heads that have 1/4 point less compression than the GTO 093 heads. The 092's are about 69cc combustion chamber vs 64cc of the 093's. They have the same valves and port sizes as the 093's. A good friend is running a '66 'big car' 389 with 092 heads, dished pistons, and a 268 XE cam in his '65 GTO and it is a screamer. The tripower will work excellently with your 092 heads. You could look in a cylinder with a borescope to determine if it has dished pistons installed. If they are flat tops, be prepared to run 95-100 octane fuel.
 

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Discussion Starter #8
Thanks for the reply geeteeohguy. I knew that the block was a '65 or '66 according to the block code of YC, which I knew wasn't original as the goat was built as a 4 speed, and later finding the block casting #9778789 and the build date casting which appears to be F106 narrowing it down to 1966. So, '66 block and heads (big car) and 3x2 intake from a '65. Thanks again!
 
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