It's in the dist. The dist. itself is the cam sensor.
if you know the proper timing for the engine, and it depends on the makeup of the eng. all 350's are not the same. you need a timing light. loosen the dist. hold down clamp,and with the eng. at an idle , shine the light at the timing mark over the harmonic balancer.if you have to change the timing, rotate the dist. very slowly ,and watch the timing marks with the timing light. when the right mark lines up with the timing pointer, lock the dist. hold down clamp, with the bolt. if the eng. starts running real rough, turn the dist. in the opposite direction.
wire that as number one or pull dist. and fix.
Take the dist cap off. mark the base of the dist and engine block so you can put it back where it was. Mark where the rotor is pointing. Pull the dist out and mark where the rotor is pointing now to facilitate replacing the dist. Remove the gear off of the dist shft. notice there is an indentation on the gear corresponding to the rotor. pull the shaft out of the dist and then remove and replace the pick up coil and make sure the relucter ring doesn't hit when tightening the screws. Reverse removal.Make SURE th e rotor is pointing the same direction EXACYLY as it was when you removed it.
Point it at #1 cylinder.
firing order, 1, 2, 3, 4, 5, 6. Dist rotation, clockwise.
if its not an electric dist. than theres a metal "door" on the side of your dist. the point above it is the first point.
If #1 piston is up on compression (hold finger over plug hole to feel air while bumping starter) put something in and rotate motor so you can tell when piston is at top of stroke. With cap off distributer rotor should point to #1 plug wire. rotate dist. with coil wire off turn over engine and move dist to get it to turn over the fastest. plug in coil wire start and time it.
There should be a sticker on the fan shroud telling you which wire to disconnect. On the older tbi motors it was tan with a black stripe i believe. Disconnect this wire, the loosen the dist. bolt and check the timing with a timing gun. Rotate the dist. until you get the desired timing then tighten the dist. bolt and connect the tan wire. On a vortec engine you have to have a engine scanner to adjust the timing. But if there is no check engine light on then the timing is correct all ready. It is controled by the computor, There is no ajustment needed.
there is an arrow on the dist cap indicating the direction of rotation.
rotate the engine to top dead center on the compression stroke on number one cyl. remove the dist. cap the rotor bug will be pointing at the number one on the dist cap. if the cam and crankshaft are timed right. timing on the wires are clockwise on the cap