Leading A-Series engine specialist since 1981
Our vernier duplex kit allows straightforward and accurate camshaft timing adjustment, which is essential to get the most from your engine.
This option features a CNC-machined 7075 aluminium camshaft sprocket to save weight over the steel/alloy version.
The steel crankshaft sprocket has an extra deep key way and full radius machined into the rear of the crankshaft mounting diameter.
The timing gear set comes complete with:
Please note that light modification of the timing cover may be required for clearance, as with all duplex setups.
See the additional information tab for weight comparisons and general recommendations.
Which cam timing setup is best?
The choice comes down to personal preference and usage. As a general rule we'd recommend the following:
Steel/alloy vernier duplex - High mileage road car, trackday and competition, 1.35kg.
All-alloy vernier duplex - Weekend road car, trackday and competition, 0.9kg.
Alloy simplex race - Trackday and competition, 0.65kg.
By nature, the steel outer teeth of the steel/alloy setup are better suited to higher mileage applications. The all-alloy type teeth are machined from a tough 7075 aerospace aluminium and will withstand vigorous use, however, so many are used effectively on the road.
Is lighter better?
The simplex type is aimed at race engines where every last gram matters, but we would not recommend this for regular road use. The lighter the rotating components in a racing engine, the faster it will be able to accelerate to its peak power band high up in the rpm range. On a standard or mildly tuned road car that's less of a concern.
Do I keep the tensioner?
No, the MED duplex vernier is designed to run without the standard chain tensioner.
What should I torque the fixings to?
The cap head adjusters do not need to be excessively tight. Either tighten by hand with an Allen key, or torque to 12 lb.ft if you have a small enough torque wrench. The camshaft lock nut should be torqued to 70 lb.ft with the locktab in place.
How about the belt drive conversion?
The belt drive conversion aims to reduce potentially damaging harmonics in the valve train and is considered to be the ultimate setup by many. We fit and use all types of cam timing setups in our engines and kits.