C i d #

Just pulled the dist. name and # on snout, Weber F 5 S, duration on intake (265) and exhaust Is (260) Lift is intake (340) and exhaust (342). should be quite lumpy.
 
More research and the LC stamped on the piston stands for low crown which inturn means low compression, so tomato taamato. I'm guessing it will the fastest flattie in town. thanks for all input. still looking for an approx. H.P rating, any educated guess's.
 
A little off the topic at hand, but I remember in shop class being taught how to figure out displacement. the equation was Bore (times) Stroke (times) number of cylinders (times) Pi (3.1416). That would make sense for say, a ford 302. 4X3X8X3.1416 = 301.59.

If you try it for the above Flathead, 3.375 X 4.125 X 8 X 3.1416 = 349.89.

You guys are saying 296". What gives?
 
Pi is to figure the area of the cylinder bore (radius squared X Pi). Multiply that by the stroke length gives the volume of the cylinder. Mulitply that by the number of cylinders for total volume displacement.

There are other ways it can be done that work but then most things in mathematics have more than one way to find the same answer.
 
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GreenMonster48 said:
A little off the topic at hand, but I remember in shop class being taught how to figure out displacement. the equation was Bore (times) Stroke (times) number of cylinders (times) Pi (3.1416). That would make sense for say, a ford 302. 4X3X8X3.1416 = 301.59.

If you try it for the above Flathead, 3.375 X 4.125 X 8 X 3.1416 = 349.89.

You guys are saying 296". What gives?
Click to expand...




That's the formula NASCAR uses when they want to disqualify a car.

Sal
 
rotorwrench said:
Pi is to figure the circumference of the cylinder bore (radius sqared X Pi). Multiply that by the stroke length gives the volume of the cylinder. Mulitply that by the number of cylinders for total volume displacement.

There are other ways it can be done that work but then most things in mathematics have more than one way to find the same answer.
Click to expand...

Ah, cool. Weird how it works one way for some but not for others. I should have prefaced by saying I'm terrible at math.
 
As I recall,the LC refers to the wrist pin location in relation to the top of the piston.
1/4" stroke=1/8 LC , 3/8 stroke=3/16 LC. Could be wrong..
 
Or use Radius squared X Stroke X Pi X 8... also works well.

1.6875 X 1.6875 X 4.125 X 3.1416 X 8 = 295.22

The reason greenmonster's numbers worked out for the 302 cu. in. example is because in the formula R sq. X stroke, etc. the bore is 4", hence 2 X 2 = 4
 
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GreenMonster48 said:
Ah, cool. Weird how it works one way for some but not for others. I should have prefaced by saying I'm terrible at math.
Click to expand...

It's because a 302 has a 4 inch bore!!! 2 pi r = area 2 X 2 = 4 so it works ether way, but only for a 4 inch bore.

Edit: Little late to the show on this one!!!
 
JSeery said:
It's because a 302 has a 4 inch bore!!! 2 pi r = area 2 X 2 = 4 so it works ether way, but only for a 4 inch bore.

Edit: Little late to the show on this one!!!
Click to expand...

I think Confucius might call that 4" thing an "anomaly". DD
 
JSeery said:
It's because a 302 has a 4 inch bore!!! 2 pi r = area 2 X 2 = 4 so it works ether way, but only for a 4 inch bore.

Edit: Little late to the show on this one!!!
Click to expand...


When I learned this in High school, I was mostly messing with 289's and 302's, so that makes sense. Both have 4" bores

I'm sure I learned it the right way, but forgot over time. Maybe not. who knows. :confused:
 
Area of a circle or bore in our case is pi r squared. (where r is the radius of the bore or half the bore diameter).
Or if you want to use the bore diameter instead of radius, pi d squared over 4.

Dividing by 4 compensates for using twice the radius and then squaring it.

Examples for a 4" bore
Using radius:
(2 x 2) = 4
4 x pi = 12.566

Using bore
(4 x 4) / 4 =4
4 x pi = 12.566

For a 3" stroke, 4" bore V8:

12.566 x 3 x 8 = 301.593

God I'm rusty on this stuff.

Mart.
 
Reminds me of the old joke of 3 guys talking about pi,
1st guy says pi are square,
2nd guy says, no! pi are round,
3rd guy says, no! pi is to eat!!!!!!!

Bob
 
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