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bored over  
moptop
New User | Posts: 12 | Joined: 07/07
Posted: 08/26/07
05:18 PM

How do you calculate the cubic inches when you bored over the motor? I got a 455 and its .30 over.  


 
CSIROC
Enthusiast | Posts: 744 | Joined: 11/05
Posted: 08/26/07
06:58 PM

455 what?  Buick, Olds, Pontiac?

You need the bore and stroke.  Then its just (pi/4) X bore^2 X stroke X number of cylinders.  You'll just add 0.030 to the bore.  


68 Olds Cutlass ~ 350 Rocket
85 Delta 88 ~ 425 Rocket
02 Silverado 4X4 ~ 5.3L

 
moptop
New User | Posts: 12 | Joined: 07/07
Posted: 08/31/07
04:54 PM

Pontiac.
bore 4.182 inches(w/bore), stroke 4.21, V8
What is the pi/4?  


 
TheSilverBuick
Enthusiast | Posts: 737 | Joined: 02/06
Posted: 08/31/07
05:20 PM

Part of the calculation.  


The Silver Buick- '77 Skylark coupe w/455&TKO-600, '72 Centurion Conv't - 455w/TH400, '67 T-bird 4Dr (suicide) w/428&C6. Needing to replace a '69 Firebird 400.

http://www.members.aol.com/thesilverbuick/Pictures/

 
waynep712
Enthusiast | Posts: 310 | Joined: 10/07
Posted: 10/13/07
01:10 PM

the simple way

bore size divided by 2.
than number times itself,
that number time 3.1416.
times stroke. times# of cylinders

like this..

4.155 divided by 2  = 2.0775

2.0775 X 2.0775 X 3.1416 X 3.48 X 8 =377.48715

its easy..

again

4.030 divided by 2= 2.015

2.015 X 2.015 X 3.1416 X 3.48 X 8 = 355.11595


be aware that not all bore sizes are exactally even..  some are under and some are over is all depends on piston diameter and cylinder bore clearance machined.    


 
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