Properly Matching Your Camshaft and Distributor Gear - Engine Builder Magazine

Properly Matching Your Camshaft and Distributor Gear

Matching camshaft and distributor gears is one of the most critical,
yet often overlooked step in engine assembly. The proper distributor
gear for your camshaft differs by both the material and the kind of
lifter for which your camshaft was designed. Using the wrong material
can lead to premature gear wear, possible camshaft wear and ultimately
engine failure.

First off, no steel distributor gear is compatible with both flat
tappet and hydraulic roller cams. This is because hydraulic rollers can
be made from two possible materials and either of those materials
requires a different gear than the flat tappet cam. Regardless, a steel
gear is not compatible with a cast iron flat tappet cam.

Distributor Gear Materials:

1. Cast Iron

2. Composite (offers great life, conforms well to the mating cam gear, and is compatible with ANY camshaft gear material)

3. Melonized or hardened steel
(material that OEMs use with factory roller cams; many aftermarket
distributor manufacturers use these as the default gears for their
distributors)

4. Bronze (conforms well to the mating
camshaft gear and will not damage the camshaft gear, but it is a self
sacrificing gear intended to be used in race applications only and
should be replaced about once a year)

If you have a cast iron hydraulic or solid flat tappet cam, your distributor gear options are:

1. Cast iron distributor gear

2. Composite distributor gear

If you have an austempered ductile iron hydraulic or solid roller cam, your two options are:

1. Melonized or hardened steel distributor gear

2. Composite distributor gear

If you have a billet steel hydraulic or solid roller cam, your two options are:

1. Bronze distributor gear

2. Composite distributor gear

COMP
Cams recommends the composite gear because it is compatible with all
camshaft gears – flat tappet, austempered cast iron cores, and billet
cores. If the steel gear is not hardened, it is not compatible with
either of the roller cam types.

Note: If you have an
austempered core hydraulic roller cam and a .500? shaft distributor
with a steel gear, verify with the manufacturer of the distributor that
the steel gear they use is a melonized or hardened steel material and
it will work fine.

 

–Tech Tip courtesy of Comp Cams

You May Also Like

LTR Engine Build

This Late Model Engines build is centered around Concept Performance’s new LTR block, which is the first aftermarket as-cast aluminum Gen V LT block. 

The Chevrolet LT engine family from General Motors is rooted in the early ‘70s, when the LT1 was featured in the Corvette and Camaro Z28. After a 20-year hiatus, GM reintroduced the platform in the early ‘90s. The “LT1 350” came out in 1991, and was distinct from the high-output Gen I LT1 of the 1970s. It displaced 5.7L (350 cu in), and was a two-valve per cylinder pushrod design. The LT1 used a reverse-flow cooling system, which cooled the cylinder heads first, maintaining lower combustion chamber temperatures and allowing the engine to run at a higher compression than its immediate predecessors.

LS Intake Manifolds

LS swaps are popular for many reasons, but there are a lot of variations and details to sort through – more of them than you may expect – and many of them are associated with the intake manifold.

LS Cylinder Heads

The LS engine is known for its cylinder heads, and there are tons of options available to upgrade the factory components.

Choosing the Correct Block for Your LS Engine Build

Whether you’re scouring junkyards, ordering cores, investigating factory options, looking at aftermarket cast iron or aluminum blocks, or spending big bucks on billet LS blocks, you’ve probably noticed it’s been harder to find exactly what you want for the foundation of your LS build than it historically has.

Open Loop/Closed Loop and Learning

Closed-loop control can be programmed to either add or subtract up to a certain percentage of fuel in order for the engine to reach the target air/fuel ratio.

Other Posts

Shop Solutions January 2023

Next time you have set of large journal small block Chevy connecting rods to resize, consider honing the big ends of them for a +.002” outside diameter bearing that the LS engines with fracture cap rods use.

Shop Solutions December 2022

Everyone misses occasionally, and this helps avoid dents and damage.

Jesel Certified Performance Rebuilds

Engine components are serious investments for any racer and maintaining that investment could be the difference between winning a championship and losing it.

Going the Extra Mile with Cylinder Head Porting

It’s not just the port work alone that creates spectacular cylinder head performance. The most critical areas of a cylinder head are those which pass the most air at the highest speed and for the longest duration. Your bowl area, the valve job, the throat diameter, and combustion chamber are all crucial parts.