alright i figured this would be a good thread to start..its so every one in here can just post formulas they know for figureing engine/car stuff out.

1.how to figure out your cubic inches .
bore x bore x stroke x .785 x number of cylinders= your cubic inches.
example
4.00 x 4.00 x 3.48 x .785 x 8 = 349.67 witch is a chevy 350

2.how to figure out your cam over lap
int duration + exh duration / by 4 - lobe x 2 = valve over lap
example
285 + 292 / 4 - 112 x 2 = 64.5

3.calculating how much cfm your engine will use(for carb selection)
engine cubic inches x max rpm / 3456 = cfm
example
355 x 8500 / 3456 = 873

4.et calculating stuff
your 1/8 mile time x 1.5832 = 1/4 time

your 1/4 mile time / 1.5832 = 1/8 time

TUEBO STUFF
5.on a turbo map ever 10lbs =144.72 cfm

6.figuring out pressure ratio from boost
atmospheric pressure at sea level is 14.7 psi so
14.7 + amount of boost / 14.7 = pressure ratio
example
14.7 + 34 / 14.7 = 3.3

7.figureing out your engine volumetric flow or EVF in cfm.
step 1
engine ci / 1428 =
step 2
engine rpm / 2 =
step 3
take step 1 answer and times it by step 2s answer witch will give u your evf.

8.figuring out your engines airflow in lb/min
step 1
your psi u plan on running x your evf x 29 =
step 2
10.73 x 460 =
step 3
take step 1s answer and div it by step 2s witch then u get your engines airflow in lb/mins