# 305 V8 .040 over makes it a 319?

Discussion in 'The Garage' started by kennyw, Feb 16, 2004.

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If I did the math right a 305 V8 bored .040 over would be a 319 right? (Going into a Camaro)

Bore Area x Stroke x 8 = CID

[(3.807/2)sq x 3.1412] x 3.480 x 8 = 319

2. ### 4X4HIGH1 ton statusPremium MemberGMOTM Winner

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No, a 305 has a standard bore of 3.735" with a 3.48" stroke which would make a .040" oversize 305 a 311.59755 to be axact.

The formula is (bore) x (bore) x (stroke) x (.7854) x (number of cylinders) = displacement

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Ok, the website I found for the 305 specs listed a 3.767 bore as std... Ok, redid the #'s with the std bore I found and it came out to 310 /forums/images/graemlins/1zhelp.gif /forums/images/graemlins/wink.gif

Ok, looks like I have a 312 V8 now. /forums/images/graemlins/thumb.gif

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[ QUOTE ]
The formula is (bore) x (bore) x (stroke) x (.7854) x (number of cylinders) = displacement

[/ QUOTE ]

That formula looks weird to me though... Lets see does .7854 x bore x bore = &amp;#960; x r x r since bore/2 = r /forums/images/graemlins/smirk.gif Guess that works but not accurate enough for my tastes /forums/images/graemlins/thumb.gif

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&amp;#960; x [(3.735 + .040)/2]sq x 3.480 x 8 = CID

3.1412 x [3.775/2]sq x 3.480 x 8 = CID /forums/images/graemlins/yikes.gif

311.55788 = CID

6. ### CyberSniper1/2 ton statusPremium Member

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Standard bore is 3.735 - 3.736.

3.736+.040= 3.776

((3.776/2)^2)*Pi*3.48=38.97 in^3/cylinder

38.97*8=311.76 inch^3 = 5.1L

My 305 is .060"
3.736+.060= 3.796

((3.796/2)^2)*Pi*3.48=39.38 in^3/cylinder

39.38*8=315.07 inch^3 = 5.16L

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