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Engine bored 30 thousands over

On engine bores, common language is .030 over means +.030 on diameter.

If you’re talking to a general machinist and you hand him a round part and tell him to take 30 thou off, YOU better tell him whether that is “diameter” or “per side”. Better yet give him a sketch with the required finished size.
 
On engine bores, common language is .030 over means +.030 on diameter.

If you’re talking to a general machinist and you hand him a round part and tell him to take 30 thou off, YOU better tell him whether that is “diameter” or “per side”. Better yet give him a sketch with the required finished size.
Oh I dunno.....for years I've just said "I need to go 30 over" and hand over the pistons if they aren't all the same. If they are all the same, I only hand over 1. However I've found that not all machinists measure the same so that's why they get a piston. It's unreal how so many machinists are that way.
 
You caaaan.. but thats usually left for the chevy crowd. " i got a 355!" " i got a 468!" type thing.
It makes my blood boil when someone tells me they have a 383 in they’re cheby. No you don’t you have a 327 or 350 stroker. I can’t even search the internet for 383 without specifying Mopar.
 
That's RC's job. I'm still an apprentice.
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OK I am back


My engine is 60 thousands over so 4.38
Where the frick did .060 come from. March your butt back to your title and your first post and you were talking about a .030+ 440. :mob: :mob: :mob:
 
OK I am back
Just was not sure what what numbers to use
From math class volume is PIE R times R times height

Factory bore of 4.320 and stroke of 3.75

22/7 times 2.16 times 2.16 times 3.75 works out to 54.98 per cylinder times 8 gives 439.89

At 30 thousands over is 4.35

22/7 times 2.175 times 2.175 times 3.75 works out to 55.75 per cylinder times 8 gives 446.03

My engine is 60 thousands over so 4.38

22/7 times 2.19 times 2.19 times 3.75 works out to 56.52 per cylinder times 8 gives 452.20

So what it boild down to is when anyone asks what engine I have I can say a 452 under my hood :)

Thanks for all the replies as I was getting stuck on did 30 thousands over mean they took 30 thousands off the wall to clean it up which would mean both sides or was the bore 30 thousands bigger in total
So what does a .055 over work out to? :mob:
It makes my blood boil when someone tells me they have a 383 in they’re cheby. No you don’t you have a 327 or 350 stroker. I can’t even search the internet for 383 without specifying Mopar.
In addition to the anger.. shouldn't it be 355 stroker?
 
It makes my blood boil when someone tells me they have a 383 in they’re cheby. No you don’t you have a 327 or 350 stroker. I can’t even search the internet for 383 without specifying Mopar.
A 383 is such a good engine they want to be just like their Mopar buddies. Someone says that to me and I ask if it's a Mopar engine. That pisses them right off. :poke: :poke: :rofl:
 
Someone probably already answered this but yes...... .015" per side so pick your side lol :D
But.....what would be the new displacement if the engine had a SQUARE cylinder bore??? That way if one side was scuffed or damaged it could be salvaged. But, I could not find anyone making square pistons.....even hyperutectic alloys........just a curiosity question.......that way calculations would be easier because everyone seems to get confused about using PI or 3.14159......(its a non-repeating decimal number).......????....
BOB RENTON .
 
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