How does everyone get a 396 small block. ive read a lot of LT1 396's. stock 350 has these specs right:
Bore: 4"
Stroke: 3.5"??
so what do yall do to get 396?

 

4.030" bore, 3.875" stroke.

4.030" x 4.030" x 3.875" x 8 cylinders x 0.7854 = 395.42 CID

 

Rippin92RS, the stroke of 350 is 3.48" not 3.50"

Jimlab, the right formula to get the cubes of a motor is = pi*(radius of bore)^2*stroke* number of cylinders

^2 means raised to the power 2 or means squared

you got it right for the bore size and stroke size but for the formula it will be =

3.14285*(2.015)^2*3.875*8 = 395.582

 

Actually, Pi is 3.14159265 etc.

3.14159265 * (2.015)^2 * 3.875 * 8 = 395.42 CID
4.030 * 4.030 * 3.875 * 8 * 0.7854 = 395.42 CID

3.14159265 * (2.05)^2 * 4.0 * 8 = 422.48 CID
4.100 * 4.100 * 4.0 * 8 * 0.7854 = 422.48 CID

The results are the same. The constant 0.7854 is simply 1/4 of Pi.

Nice, huh?

 

jimlab, that is good, you prooved your other formula. i thought there was one formula for the displacemtent .

your other formula is this way

r = radius

(2*r)^2*stroke*8*pi/4 which is actualy

the same as 4*r^2*stroke*8*pi/4

the first 4 will cancel the other 4

and the result will be =
r^2*stroke*8*pi

which is excatly the same as the other formula

i thought pi = 22/7 = 3.142857143

where i learned that in elementary school, maybe something changed or it was an approximation

but yeah, you are right pi is 3.141592654 which what i found in my casio FX-880 scientific calculator.

btw jimlab, how is your 396? do you have GTP ported AFR heads in the 396? what do they flow and what is the intake port volume? do you have any 1/4 mile #'s? thanks.

 

My 396 is waiting to go back on the dyno cell with the new ignition setup (MSD crank trigger, MSD cam sync stub, FAST eDist electronic distributor and 8 LS1 coil packs) right now. We should get a weekend in mid-April, hopefully.

My heads are custom cast reverse flow AFR 215cc Raised Runners delivered bare and opened to about 213cc on the intake runners with porting, so velocity is still high. With a direct shot at the back of the intake valve, they flow in the high 330s from 0.650" up.

No quarter mile times yet, still waiting on too many parts, including the engine.