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· 64-67 Expert
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Sorry, I missed both the block date and the fact that there was a YH in 1969 as Jim pointed out.

Okay, I might be really loopy tonight, but neither the crank nor the caps are anywhere near being for a 428 Pontiac. They just don't make that big of hammer to beat it in place, and I swear the only thing I've been drinking is coffee. I couldn't find 428 photos so I'll make do with a photo of 3-1/4" 455 crank and caps. The above photos in post #10 look like something for a 4-bannger engine consider the narrow width of the rod journals and the small mains (and thrust is on #3 on that small crank).
View attachment 161138 View attachment 161139
I pointed out in post #3 that it was a '69 360 HP engine. Two bolt main. I had one just like it. Many engines are cast late in the year prior to the model year. Thus, a '68 cast date for a '69 model year car. The crank and caps pictured appear to be Model A or B Ford. It's a 4 banger with not much counterbalance. Could be an old Dodge, etc. too. Or a zillion others. I still have the crank out of my '69 428 and it is available. It'll need work, but it's a factory GM 428 crank. The shipping would likely make it cost prohibitive.
 

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If you haven't already go on Butler's site under the tech tab where they have all kinds of charts for cubic inch combos and compression calculators, motor identification, they have all the rotating assemblies you could imagine. It's fun to dream what you could do but make sure you're sitting down because they ain't cheap but they're probably the best in the land.
 

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66 GTO post coupe
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406 Posts
Discussion Starter · #23 ·
the aftermarket caps are drilled in two bolt blocks all the time.those other holes on your block are for the dowels to locate the caps. two bolts are pretty stout but if you cant find the original caps. the new caps may be the way to go.
Have the shop put in main studs then 2 bolts are good enough that's what Butler did to my 461, it's not like you're going to be spinning it above 6000 rpms...are you?
If you haven't already go on Butler's site under the tech tab where they have all kinds of charts for cubic inch combos and compression calculators, motor identification, they have all the rotating assemblies you could imagine. It's fun to dream what you could do but make sure you're sitting down because they ain't cheap but they're probably the best in the land.
Thanks for the info, I’ll use that crank for a boat anchor, just got done cleaning the block & heads & sprayed it inside and out with mystery oil & trans fluid, looks really good and didn’t see any glaring issues. Two bolts are enough for me so I’ll be looking into everything else soon as well as all the great posts about engines on this great forum !!
 

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Now would be the time to take a rough bore measurement since many of the blocks this old are on their second or third life. Stock bore is 4.120".

If you can, find a shop that will "shake-and-bake" the block for cleaning. This entails the block being heated up to around 450° and then tumbled in steel shot to get it squeaky clean. I use a particular shop just for this cleaning process and magnafluxing, and then use another for the actual machine work. We have a shop locally that has the old fashion hot tank still in business from the 50's and while I admire the effort it took to keep it active with all of our state's EPA insanity, it still doesn't produce the results of baking a block to rid it of paint, grease, and calcium buildup. The crank photo I pictured above was with the old hot tank method and even after an additional hour or so of cleaning after I got it home there is still rust and paint on the block. Here is a photo of a block back from the shake-and-bake but prior to my scrubbing it down. It sat out in someone's back yard for years before I rescued it and had its fair share of rust and gunk.
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Pull out all the gallery plugs if you can or pay the shop to do it before the cleaning process and also have them remove the cam bearings. Unless you have the proper tool, don't hammer them out - very easy to damage the block by chisel gouges. If it passes magnafluxing, then have the shop pull all your main cap dowel pins. Those remaining in your block have been driven down almost flush and need to come out. Shops have a special tool as long as there is enough sticking up to get the tool to bite into the dowel, otherwise they will weld on a bolt to the dowel to get pull out.
 

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66 GTO post coupe
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406 Posts
Discussion Starter · #25 ·
Now would be the time to take a rough bore measurement since many of the blocks this old are on their second or third life. Stock bore is 4.120".

If you can, find a shop that will "shake-and-bake" the block for cleaning. This entails the block being heated up to around 450° and then tumbled in steel shot to get it squeaky clean. I use a particular shop just for this cleaning process and magnafluxing, and then use another for the actual machine work. We have a shop locally that has the old fashion hot tank still in business from the 50's and while I admire the effort it took to keep it active with all of our state's EPA insanity, it still doesn't produce the results of baking a block to rid it of paint, grease, and calcium buildup. The crank photo I pictured above was with the old hot tank method and even after an additional hour or so of cleaning after I got it home there is still rust and paint on the block. Here is a photo of a block back from the shake-and-bake but prior to my scrubbing it down. It sat out in someone's back yard for years before I rescued it and had its fair share of rust and gunk.
View attachment 161145

Pull out all the gallery plugs if you can or pay the shop to do it before the cleaning process and also have them remove the cam bearings. Unless you have the proper tool, don't hammer them out - very easy to damage the block by chisel gouges. If it passes magnafluxing, then have the shop pull all your main cap dowel pins. Those remaining in your block have been driven down almost flush and need to come out. Shops have a special tool as long as there is enough sticking up to get the tool to bite into the dowel, otherwise they will weld on a bolt to the dowel to get pull out.
Great information, I’ve never heard of the shake n bake before but I’m going to look into it around here, everybody I knew “hot tanked “ them but I’m talking about back in the day. Your block looks great like new ! Hopefully this one hasn’t been punched out too many times, I’ll get a measurement before anything else, how big is too far gone? Thanks!
 

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Great information, I’ve never heard of the shake n bake before but I’m going to look into it around here, everybody I knew “hot tanked “ them but I’m talking about back in the day. Your block looks great like new ! Hopefully this one hasn’t been punched out too many times, I’ll get a measurement before anything else, how big is too far gone? Thanks!
To me, looking at the tops of the cylinders, it looks like it has never been punched out. Looks like a virgin std. bore block to me. I always try to go as little as possible oversize. .020" or .030". .060" oversize for this era of Pontiac block is about the limit. I like the idea of someone long after I'm gone being able to rebuild my engines again and enjoy them in the future decades from now. And not do an LS swap. LOL...
 

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66 GTO post coupe
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Discussion Starter · #27 ·
To me, looking at the tops of the cylinders, it looks like it has never been punched out. Looks like a virgin std. bore block to me. I always try to go as little as possible oversize. .020" or .030". .060" oversize for this era of Pontiac block is about the limit. I like the idea of someone long after I'm gone being able to rebuild my engines again and enjoy them in the future decades from now. And not do an LS swap. LOL...
I pulled out the old dial caliper and took a couple measurements, looks like 4.13 ish, so probably pretty good still, and the caliper may read a fraction much as when it’s closed it reads + 1 tick, let me know what you think, also got a old edelbrock pontiac torker # 2720 intake, what do you think of the combination 69 428, 69 #46 heads & this intake ? My intention: old man with cool ass GTO, cruising around town, sounding awesome doing the very occasional burnout, no racing but I do like it when the passenger has to “try” to reach the grab bar!!
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I'm no expert but I don't think that's the best choice of an intake for what your intentions are...going to hurt the low end. I think that manifold is rated for 3000- 7000rpms without checking and is pretty tall so hood clearance could be a problem depending on the air cleaner. I'm running a Performer RPM with a 1/2" phenolic spacer on my 461. Just my thoughts.
 

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66 GTO post coupe
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Discussion Starter · #29 ·
I'm no expert but I don't think that's the best choice of an intake for what your intentions are...going to hurt the low end. I think that manifold is rated for 3000- 7000rpms without checking and is pretty tall so hood clearance could be a problem depending on the air cleaner. I'm running a Performer RPM with a 1/2" phenolic spacer on my 461. Just my thoughts.
Thanks for the reply, I have my stock 66 4 bbl & tripower so I’m good on intakes, that edelbrock was just part of the pile of stuff
 

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I think the block is worth the effort of a hot tank and mag. If nothing serious is revealed, I'd build it! Mine was born a 4-bolt main. I've let this sit for a while as I'm trying
to finish up on other priorities, but I am going to use #96 D ports and a factory aluminum 2-piece intake on this build. Good luck on your build and keep us updated!
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1964 GTO, Tri-power, 4 speed, manual brakes & steering, black ext. red int., dog dish caps, T.I. ign
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And it’s a 1968 428 block # 9792968
& #46 heads, if I build it would 4 bolt mains be necessary or even possible on this block? Here’s a pic of the area, there are holes with short studs, can they tap those holes for bolts ? View attachment 161140
Your block number is the same as my 428-9792968 which is at the machine shop in progress. The engine code on mine is XF. Mine has the 4 bolt main caps, so I assume you can adapt to the 4 bolt main set up. I don't know what the criteria was for 4 bolt vs 2 bolt?
 

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Discussion Starter · #32 ·
Your block number is the same as my 428-9792968 which is at the machine shop in progress. The engine code on mine is XF. Mine has the 4 bolt main caps, so I assume you can adapt to the 4 bolt main set up. I don't know what the criteria was for 4 bolt vs 2 bolt?
Mine is YH and is a 2 bolt main, for my basic plan of a mild build most advice I’m getting is to leave it as is unless you’re going for 500+ hp & 6000 rpm or more. Just gonna be a street engine. 👍
 
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