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440 Pistons in 383

zsn0w

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Hi all,
I found a good deal on a 1967 383 block close by, but it's already bored .030 over and the cylinders are pitted a bit and probably will need another .030. Do you think the block could handle another hundredth over that to get it to 4.32, and would I then be able to use standard bore 440 pistons in it? Or should I just forget about it since it's already so bored out. The only other 383 block I can find close by for a good price right now is $50 more, surface rusty pretty much everywhere, but standard bore (and it's a further drive, which does play into it a bit more with gas prices today).
Thanks,
Zack
 
The only way to know how much overbore the block can handle is have it sonic thickness tested. are you sure it would take .030 more to clean it up? if so i would probably pass and wait for a better block.
 
Not sure how much further away the other block is but I'd rather get that one - if a 0.030 overbore can clean it up.
 
It can be done. Use a 440 low compression piston.
A 72 year model low compression piston will be almost at zero deck height.
But as said before not all blocks can go that far and I would have the cylinders checked for
thickness.
 
upload_2022-3-31_8-46-7.jpeg

This is the only picture of the bores that was posted on the one that is already 30 over, by the way. I sent messages to both asking for some more details.

What do you guys think the odds are that any given 383 block can handle 70 over? Don't need anything super specific just wondering if I'm looking more at 50/50 chance it works or more like a 1 in 10. I might be able to get that one for $100 so it could be worth trying. The main advantage is that I will probably already be going through where that block is for another trip, so it wouldn't really cost me any extra gas.
 
Just went .60 over on my 67 383 with no issues found( still in assembly). Piston at deck height and with heads ordered, CR is estimate at 10.4
 
upload_2022-3-31_8-55-11.jpeg

This is the only picture of the rusty standard bore one that was on the listing. Pretty hard to tell what’s going on with it since the one bore looks like it was cleaned up and seems like it could be okay? Asked for more info on that because it’s just too hard for me to tell if it’s all surface rust or worse.
 
I built a 400 using 440 pistons. Be prepared for a balancing bill as the 440 pistons are substantially heavier.
 
Found mine on E bay. 400 for the block stock bore. Plus, shipping. Troy Michigan. Too Fl. Went 20 over to clean it up. Built an A/C car and rather have less bore so the motor would not run hot in traffic with A/C running. My builder put Half dome piston's in to bring my compression ratio up. Could do that with the 906 head's due to the dome in them. Fly cut valve reliefs. Very happy with how it turned out. That old rusted up block would be a pass for me. Like was stated a better one is out there. The 383 does not have a lot meat between the oil and water jacket's to the cylinder wall's. Good luck on the hunt and know if you look more there is a motor out their. Blue
 
View attachment 1262697
This is the only picture of the rusty standard bore one that was on the listing. Pretty hard to tell what’s going on with it since the one bore looks like it was cleaned up and seems like it could be okay? Asked for more info on that because it’s just too hard for me to tell if it’s all surface rust or worse.
Just remember, every machined surface should be re-machined. That's pretty rusty.
 
Last edited:
The rusty block is scrap. re-machining all the required surfaces would cost a ton, probably nearly $3,000.
 
Hi all,
I found a good deal on a 1967 383 block close by, but it's already bored .030 over and the cylinders are pitted a bit and probably will need another .030. Do you think the block could handle another hundredth over that to get it to 4.32, and would I then be able to use standard bore 440 pistons in it? Or should I just forget about it since it's already so bored out. The only other 383 block I can find close by for a good price right now is $50 more, surface rusty pretty much everywhere, but standard bore (and it's a further drive, which does play into it a bit more with gas prices today).
Thanks,
Zack

From what I heard over the years, the '67-70 383 blocks can usually take .060 with no problem. Sonic testing will tell you how good it will be. It would be a better plan to get custom pistons than chance a heavy standard bore 440 with questionable deck height results.
 
I have one that needed to .060. Had it sonic tested. Builder said there was enough wall thickness
 
The first block looks like it will hone to 0.040", but without seeing ALL of the cylinders, it is hard to speculate. The second, rusty block could be fine too and possibly clean up at 0.020" or 0.030", but again hard to tell in just a pic. Here is a 440 that started out the same way, and I: strip, wash, and glass bead to completely clean the block to evaluate. I have already align hone the mains, and after a rinse, it will go to the mill to square, then bore. If you are worried bout the lifter bores, nothing that a ball hone can't clean up.

IMG_0098.jpg IMG_0099.jpg
 
It almost looks like that block was hot tanked and then left out to rust. There doesn't seem to be any paint on it at all.
 
It sounds like the op is trying to save money... That usually doesn't work out. Save on pistons by using some used stuff that doesn't fit and spend on the balance, as well as the regular machine work and end up with a motor that is disappointing. I would say to spend on a good 440 or 383 block, and build it right, and you will be happier in the end, with all of the work and trouble that you will go through. There is nothing wrong with using used parts, as long as they are in good shape and fit correctly... trust in all those engineers at Chrysler corp. back in the day... there is reasons why they didn't do things like boring over .060... etc. Just my opinion. ( I get tempted to try stuff like that all the time, but usually talk myself out of it because it winds up being a "can of worms")
 
If this is the basis of a performance build, be aware that 440 pistons & pins are veeeeeeery heavy, about 1100 gms.
 
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