Cam Gear… Single row… Double Row…
Upgrading the camshaft in your LS will have a domino effect on a few things that will require you to replace/upgrade some other related components so everything works as it should and reliably!
VCM Performance’s range of Camshaft are all made with a 3 bolt pattern on the front, this in most LS engines isn’t compatible with the factory single bolt style. So the need to upgrade the cam sprocket is a necessity.
There a few different kits available to get this done, and a couple different variations of them as well. Its purpose is really quite simple; Firstly – Allows a chain to be fitted to time the camshaft to the rotation of the crank so as all the valve train can operate at the time needed for the engine to run, perform and not foul pistons and valves. Secondly on GENIV motors, it allows a camshaft sensor to read the camshafts position and sends this information back to the ECU so it can correlate it to the crankshafts rotation.
This second point is an important one, there is 2 types of cam triggers and they directly relate to the reluctor wheel on the crank and the type of ECU, mixing these will cause issues with the engine starting. The cam triggers are referred to as “Half Moon” which suits 24x crank reluctor wheels found in VZ HSV LS2’s (also LS1’s but cam sensor position is in the block) and “4 Point” which suit 58x crank reluctor wheels found in all VE-VF engines including VE HSV LS2.
They can be easily identified by looking at the front of the sprocket and noting what the raised trigger sections resemble. The half-moon essentially looks like a half moon, it’s an on-off style trigger, with the 4-Point having 4 raised sections; 1 small, 2 large, 1 small consecutively.
With this determined the style of kit can be decided on. Cam Gear, Single Row or Double Row!
For simplicity of install the Cam gear is a very popular option, as all that is required is to bolt it up to the new camshaft reusing the original timing chain and away you go – no need to drop the sump and remove the oil pump. While easy and convenient, reusing the factory chain can be down fall of your new camshaft install. Factory chains more so in high km engine are known to stretch. Stretched chains have a much higher failure rate especially when used with a new aftermarket camshaft, and new stronger and stiffer valve springs.
Upgrading to a single row while does involve a little extra labour to install, there are some definite benefits though. The added labour comes from the need to remover the sump, pick up tube and oil pump to gain access to the crank gear and chain so it can be swapped with the new ones included with the single row kit. Swapping these over obviously gives you a new stronger chain and also the ability if needed to adjust the cam timing in 2° increments in both retard and advance directions for high end engine builds.
Stepping up to the double row again like each of the other options has its own pros and cons. Much like the single row it has that new chain reliability but even more added strength due to the double row of chain links. This added width does have a flow on effect with a couple other things though. The first, the oil pump needs to be spaced out from the block at its mounting points to allow clearance of the chain around the crank sprocket, these spacers are included in the kits so it’s not a troublesome thing to do when everything is going back together, but in all engines apart from LS1’s the timing cover will need to machined/linished/grinded down in some areas to allow it to fit flush back against the block.
Something to keep in mind…