what to set timing at on a 350 chevy

(Paradigm/Jeff Smith)

Dropping a benefactor into the engine is a time-honored procedure that has been effectually since the first engines coughed their way to life more than 100 years ago.

With the latest generation of benefactor-less engines, this tribal knowledge has slipped from its "must-know" condition. But if you are working on an older engine with a benefactor, this is essential information.

The process is piece of cake and it volition take longer to read nearly than to really perform the task, so let's get started.

For this procedure, we will utilize a small-scale-block Chevy because that was the closest engine for the photos. However, the procedure nosotros'll describe is exactly the aforementioned for whatsoever four-stroke engine.

Our particular engine is a brand new Chevrolet Goodwrench crate engine on which we've already installed a new intake manifold.

In our case, the spark plugs were all removed, which makes turning the engine over very easy. If the engine is in the machine, you tin use the starter motor to crank the engine.

With the Number I spark plug removed, place your thumb over the pigsty while turning the engine. Once you feel pinch edifice, look for the zip mark on the harmonic balancer to arroyo the timing tag. We prefer to set the initial timing for most engines at ten degrees Before Height Dead Centre (BTDC).

With that gear up, remove the cap from the distributor. Nosotros're using a Top HEI benefactor. Nosotros use a black Sharpie to identify a marker on the distributor body where nosotros want the Number One spark plug wire to be located. This can be placed anywhere you like, but if you are a Chevrolet traditionalist, this ends up roughly at nearly the 5 o'clock position on the distributor every bit you are looking at it from the front end of the engine.

Also place a mark on the respective Number One plug wire position on the distributor cap. We used a slice of masking tape.

With these marks in place, drib the benefactor with the gasket into the distributor hole with the rotor pointing near the Number One mark.

As the benefactor drive gear engages the teeth on the camshaft, this will motility the rotor slightly clockwise. Position the distributor and so that the vacuum advance canister is located on the passenger side of the engine pointing roughly forward. If the rotor is not pointed close to the Number One marking, pull the distributor and re-position the rotor until it comes close.

Unless y'all are very lucky, the benefactor will not drop fully into the intake manifold. In well-nigh all cases, the distributor will sit most 3/eight inch off of the manifold. This is normal and is caused past the oil pump drive not engaged into the drive tang in the benefactor. You tin remove the distributor and attempt to re-orient the oil pump bulldoze slot with a long straight screwdriver, only this is somewhat difficult.

It's easier to get out the distributor in place and and so bump the engine with the starter motor while placing very light downward pressure on the distributor body. Later a half rotation or so, the benefactor will drop in place. Now we volition need to creepo the engine until again it is located at 10 degrees BTDC. With this accomplished, check to ensure the rotor is pointed near the mark on the distributor body for Number One spark plug wire. If the rotor is not pointing at Number One, yous could twist the benefactor body, but if it is off by more than one tooth, this volition require turning the distributor trunk too far. Instead, y'all will need to remove the distributor and echo the previous process as the rotor is not in the right position.

With the rotor close to the Number One position, twist the distributor trunk until the rotor points directly at the Number One spark plug final position mark on the distributor. Now install the distributor cap and cinch the benefactor body down to the intake manifold with the hold-down clamp. Tighten this lightly—nosotros may accept to movement it once more when the engine starts.

With the benefactor in place, install all of the spark plugs. Now we tin connect the spark plug wires to the distributor.

Let's assume that you've never done this before. Before we can place the wires in the distributor cap, the kickoff thing we need to know is which management the rotor turns.

For our Chevrolet engine you'll note that the rotor turns clockwise. Small- and big-block Fords plow counter-clockwise.

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Tech Tip: One quick mode to tell on any vacuum accelerate style distributor is to lay your manus parallel with the vacuum advance canister and and then curlicue your fingers inward toward the middle of the distributor body. The management your fingers indicate is the direction of rotor movement. On a Chevy distributor, you lot would utilise your left hand, and on a Ford yous'll utilise your right mitt. This is a cool little trick you can utilize on any benefactor to determine its rotation.

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On small- and large-block Chevy engines, the Number One cylinder is ever the driver's side front.

Chevrolet besides numbers its cylinders with odd numbers on the left (commuter) side and fifty-fifty cylinders on the right.

The left side is numbered 1-3-5-seven, and the right side is 2-4-six-viii.

Ford does it differently. Ford numbers its cylinders with Number One on the right front, numbered on the right side one-2-3-4 with the left side 5-6-7-8. Other manufacturers number their cylinders differently, so you should cheque online if you're not sure.

See OnAllCylinders' firing order crook sheet for installing the plug wires in the correct lodge.

Our small-block Chevy firing club is 1-8-four-3-6-five-vii-two, so that's the order in which we will install the plug wires.

We started with Number I and worked our fashion around the distributor cap clockwise using a set of Summit spark plug wires. The best way to do this so you don't become dislocated is to only follow the firing order installing each plug wire through the order.

Leave a trivial extra room with the spark plug wires to let liberty of movement in the distributor. For Chevys, be careful to make sure 5 and 7 are installed correctly. If the wires are accidentally switched, the engine volition not exist happy.

Before we try to starting time the engine, exist sure the distributor is connected to switched power. With an HEI benefactor, there is a iii-wire inboard connector between the HEI module and the cap.

On the outboard side of this connector, there are two smaller individual connectors—ane for ability from the ignition switch (marked BATT) and the other for a tach. With those connections in place and the distributor, plugs, and wires connected, we're nigh ready to get-go the engine.

Connect a timing lite to the Number One cylinder. Now we're ready to fire the engine. Bold the engine starts, brand certain the engine is idling at proper idle speed and not on the fast-idle cam of the asphyxiate.

It'southward important that the engine be idling at its warm-idle rpm. It's likely that our static ignition timing at the crankshaft at idle may not be the desired 10 degrees BTDC.

If information technology must exist changed, just loosen the agree-down nut and adjust the distributor until the initial timing on the crankshaft is at the desired timing figure. Of course, you are free at this point to set the initial timing at its proper spec.

Nosotros will save the discussion about initial, mechanical, and vacuum advance for a subsequent story, but you now have the distributor gear up in identify and the plug wires installed correctly and it's entirely possible that the engine will run much meliorate now with a properly timed ignition.

These are the parts nosotros'll use for this distributor install, including a new Peak HEI distributor, ninety-degree plug wire ends for the male ends on the benefactor and a distributor hold downwards clamp. (Prototype/Jeff Smith)

We marked where we wanted the Number Ane spark plug wire positioned on the distributor body. The factory placed it in this location on most Chevy distributors. We marked the body and placed a slice of tape on the cap. (Prototype/Jeff Smith)

Side by side, we used the bolt on the crankshaft clockwise to turn the engine until we felt pinch in the Number One spark plug hole and placed the balancer at 10 degrees before superlative dead center (BTDC). (Image/Jeff Smith)

(Paradigm/Jeff Smith)

Notation inside the distributor bulldoze gear is a male tang that volition engage the oil pump drive slot to spin the oil pump every bit the benefactor rotates. This tang becomes important when we drop the distributor in place equally the tang will likely not appoint the oil pump drive. (Image/Jeff Smith)

Place a break-in lube or engine oil on the distributor gear and with the gasket on the distributor, drib the distributor in the pigsty in the manifold. Line the rotor slightly counterclockwise of the mark on the trunk and engage the gear teeth. The gear teeth are curved which will swing the rotor slightly. You may have to play with this a couple of times to place the rotor in the right position. (Image/Jeff Smith)

You have about a twenty-percentage take chances of dropping the distributor all the way down to sit flush on the intake because of the oil pump drive tang. Information technology's near guaranteed that the distributor will sit down off the intake manifold and look like this. Do not force the distributor downward. (Paradigm/Jeff Smith)

To engage the oil pump bulldoze, put very low-cal pressure on the superlative of the distributor housing and rotate the engine clockwise until the distributor drops into identify on the manifold. Once the distributor drops in, install the distributor hold-down clench and tighten it slightly. (Prototype/Jeff Smith)

Now rotate the engine clockwise with your finger over the Number 1 spark plug hole until the rotor again achieves 10 degrees BTDC while noting pressure on your finger over the spark plug hole. Too brand sure the rotor is all the same pointing at the mark indicating Number 1 position on the distributor. Install the benefactor cap, making sure the record marker is lined up with the Sharpie mark on the distributor body. (Image/Jeff Smith)

To determine distributor rotation, align your hand with the vacuum advance canister. The direction your fingers curl will reveal the distributor's management of rotation. In this case with a Chevy distributor, the rotor spins clockwise. (Image/Jeff Smith)

We like to place each wire on the spark plug and route them to the benefactor kickoff. And so nosotros measure each plug wire separately allowing room to twist the distributor to set concluding timing and then crimp the HEI male concluding on the wire. We place a small corporeality of the supplied lube in the boot to go far easier to push onto the wire. (Image/Jeff Smith)

With the distributor in place and the wires installed, the only thing left to do is set the initial timing. (Prototype/Jeff Smith)

We started the engine and checked our initial timing and found it was slightly advanced at 16 degrees so we pulled it back to 10 degrees which also slowed the idle speed to around 850 rpm. (Image/Jeff Smith)

Author: Jeff Smith Jeff Smith has had a passion for cars since he began working at his grandfather'southward gas station at the historic period x. Later on graduating from Iowa State University with a journalism degree in 1978, he combined his two passions: cars and writing. Smith began writing for Car Craft mag in 1979 and became editor in 1984. In 1987, he causeless the role of editor for Hot Rod magazine before returning to his get-go dearest of writing technical stories. Since 2003, Jeff has held various positions at Car Craft (including editor), has written books on pocket-sized block Chevy operation, and even cultivated an impressive collection of 1965 and 1966 Chevelles. Now he serves as a regular contributor to OnAllCylinders.

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Source: https://www.onallcylinders.com/2020/04/16/how-to-install-a-distributor-and-set-initial-timing/

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