Author Topic: What's my displacement? Help!  (Read 1698 times)

Offline Bearcuda

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What's my displacement? Help!
« on: May 01, 2007 - 05:39:48 AM »
Alright you motor gurus, help me out here. I'm trying to determine what my 440s displacement is since it had a .040 over bore. According to the 1969 specs, the 440 had three slightly different bore and strokes:
1969 Cu. In. 340 383 440 Bore (in.) 4.04 4.25 4.32 Stroke (in.) 3.31 3.38 3.75 Compression 10.50:1 10.00:1 10.10:1 Induction 1x4 bbl. 1x4 bbl. 1x4 bbl. Horsepower/RPM 275/5000 330/4400 375/4600 Torque (lbs.-ft.)/RPM 340/3200 425/3400 480/3200
I know the formula is (bore area x stroke)x # of cylinders right? If the bore is one of those above numbers, what is the bore area? What's my cid?
1973 Cuda 440
1971 Javelin SST




Offline matt63

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Re: What's my displacement? Help!
« Reply #1 on: May 01, 2007 - 08:04:33 AM »
The 440 only had one bore and stroke.  I believe the stroke is 3.75 and the bore is 4.32.  Boring an engine to increase displacement gives a negligible increase in displacement as hp is lost due to thinner cylinder walls.
Matt in Edmonton

'68 Valiant
'73 Cuda 340 4 speed (408) SOLD

Offline moper

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Re: What's my displacement? Help!
« Reply #2 on: May 01, 2007 - 08:36:08 AM »
4.325 bore, 3.75 stroke. with a .040 overbore, actual displacement will increase to 448 cubic inches. .030 over is 446, .060 over is 451

Offline Bearcuda

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Re: What's my displacement? Help!
« Reply #3 on: May 02, 2007 - 06:18:47 AM »
Hmmm, could it be .40 instead or is that way too much? What's the deal with those multiple numbers I got for mopar 340/440 for 1969?
1973 Cuda 440
1971 Javelin SST

Offline matt63

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Re: What's my displacement? Help!
« Reply #4 on: May 02, 2007 - 07:50:38 AM »
Those multiple numbers are for the 3 engines listed in sequence ie the 4.04 is for the 340 and the 4.25 is for the 383 and the 4.32 is for the 440.
Matt in Edmonton

'68 Valiant
'73 Cuda 340 4 speed (408) SOLD

Offline Bearcuda

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Re: What's my displacement? Help!
« Reply #5 on: May 02, 2007 - 10:50:27 PM »
Those multiple numbers are for the 3 engines listed in sequence ie the 4.04 is for the 340 and the 4.25 is for the 383 and the 4.32 is for the 440.

Oh yeah, duh. :banghead:
1973 Cuda 440
1971 Javelin SST

Offline PlumCraZRT

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Re: What's my displacement? Help!
« Reply #6 on: May 04, 2007 - 12:18:01 AM »
mmmmm.... Mopar.... *drool*

Offline black71

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Re: What's my displacement? Help!
« Reply #7 on: May 04, 2007 - 03:06:52 PM »
.785 x bore x bore x stroke x # cylinders
.785 x 4.36 x 4.36 x 3.75 x 8 = 447.676 cubic in.