How many cubic inches do u get from an overbore?

[Bens69PlymouthSatellite]

just curious to ask some of u guys say I have a 440 and bore it .030 over what cubic inch would i end up with?

 

[69HEMICORONETR/TCONV]

about 6,......so you would roughly have a 446, ....When you overbore and buy pistons just to get cubes, ....That's an expensive way to get cubes and you won't get much for you money. ......I bore mine entirely on cylinder wall condition.

 

[moparstuart]

i agree only bore it if you need too

 

[Bens69PlymouthSatellite]

Actually I knew that...

I was just trying to explain to this guy i know that his dad has a 360 engine bored .030 over which would mean he has a 366 and he is consistently telling people his dad has a 6.1 liter engine which is a 372 which would be .060 over,and he keeps telling me im a moron so i figured if i had some more evidence to back up my argument maybe he would get the point,he tells people hes a mechanic when the only thing ive seen him do so far is strip out some cylinder head bolts and 2 of my sockets thank god they were craftsmen!I dont approve of people telling other people they are mechanics and making promises to fix/build cars for them when they dont know how to do **** but memorize a manual and not very well sorry if it seems to be a waste of your time but i want 2 stop this dude in his tracks before he does some serious damage to somones vehicle, thanks.

 

[daredevil]

cylinder bores smaller on a 360. .060 over is a 371 if i did my math correct when i did mine

 

[69HEMICORONETR/TCONV]

cylinder bores smaller on a 360. .060 over is a 371 if i did my math correct when i did mine

That sound about right, ......but just for the record .030 does not automaticaly equal 6 cubic inches on all engines, that's just what it comes up to starting with a 440 or (439.6) to be exact, A .030 would be less than 6 on a smaller engine and a little more on a larger one.

 

[Bens69PlymouthSatellite]

Thanks again!

So in other words theres no way in hell he has a 372,unless he had his engine bored over by some magical machine shop we are all not aware of,thanks alot, this guy is a giant pain in my ***.

 

[69HEMICORONETR/TCONV]

So in other words theres no way in hell he has a 372,unless he had his engine bored over by some magical machine shop we are all not aware of,thanks alot, this guy is a giant pain in my ***.

If he has a 360 block with a .030 overbore and a stock crank, rest assured he does NOT have 372 cubic inches,:no: .........It's Impossible.

Ben, I don't know the Guy you are talking about, but I know his kind, they seem to know everything and really know nothing. :grin:

 

[Meep-Meep]

Yeah, for a rule of thumb I use 6 CI for .030" overbore on a V8.

The formula is simple. It's just area of a circle times the depth. Bore squared X .7854 X stroke X number of cylinders. This is standard to figure out volume for any cylinder. Now tell him to put that in his pipe and smoke it! Unless he's smoking something else then that is the problem!!

 

[85 dually]

I do not have a B body, but sure do appreciate the information on your site. I use it all the time in my 1 ton crawler build. In response to the displacement questions from back in January:
Displacement Calculation for a 360 Engine

cylinder volume = Pi x radius squared x height of cylinder
stroke 3.580 (= height of the cylinder volume calculation)
bore 4.000 (= diameter, so the radius = ½ of that, or 2.000”)
Pi = 3.14159...

cylinder volume = 3.14159 x (2.000x2.000) x 3.58
engine volume = cylinder volume x the number of cylinders (8)
Stock 360 = 359.901 cubic inches
.030 over = 365.299 cubic inches
.040 over = 367.099 cubic inches
.060 over = 370.698 cubic inches

Thanks for the good information you guys post.

 

[Bens69PlymouthSatellite]

is there any mathematic problem or set up that would give this guy a 372? Like a big *** stroke, along with the bore?

 

[morbidgoat]

i dont know but if the motor was stroked 372 sounds like a small stroker kit? maybe hes going around saying its a 6.1 because he wishes he had a modern hemi in it. idk

 

[MarPar]

So in other words theres no way in hell he has a 372,unless he had his engine bored over by some magical machine shop we are all not aware of,thanks alot, this guy is a giant pain in my ***.

Probably a Chevy guy :rolling:

 

[Bens69PlymouthSatellite]

this is also a guy who claims to have engineered the viper and the gen lll hemi,even though he broke my factory air sensor removing it from the airbox,seems to me if he engineered it he may have been able to remove that more strategically,also can you even be a chrysler enginner without a degree??? He does'nt have one.His son is actually on this forum and hes not a bad kid, I kinda would like him to see this thread, even though he will be angry, maybe it will teach him to learn the facts from books rather than repeating second hand misinformation that his dad is leading him to believe.Somtimes people need a wake up call, and im not even a mechanic, im only learning but i can already see through him, and I tell people "Im no mechanic"., I dont just screw some parts together and claim to be an engineer.

 

[RM23M9A]

So, if one has a FACTORY 440 block, with the "A" or .020 overbore, thats close to a 444 c.i.?

 

[33 IMP]

Bore times bore times stroke times number of cylinders, times .7854 (math constant, reduction of pi) so.....
Stock bore 440... 4.32x4.32x3.75x8x.7854 = 439.7 cu.in.
Twenty over 440.....4.34x4.34x3.75x8x.7854 = 443.8 cu.in. so yes, 444.

 

[RJRENTON]

The old cylinder volume calculations apply.
A (area)= 3.14159 X r (cylinder [in inches] RADIUS squared x H (stroke length in inches) X number of cylinders
Keep the units the same....inches, centimeters, or what ever you prefer. If using decimal numbers, go to 3 decimal places. Or go to Google look up volume calcs for a fill in the blanks canned program.
BOB RENTON

 

[Charger Dana]

So, if one has a FACTORY 440 block, with the "A" or .020 overbore, thats close to a 444 c.i.?

10 year old thread, but the math is still the same. It’s not fake news, it’s science. Pi x r^2 x h. Pi Times r-squared times height.

So within rounding, yes.