LS Cam Upgrades, why do they gain so much?
Upgrading the cam in your LS engine, whether it’s an LS1, 6.0L, LS3, LSA, or LS7, can significantly boost performance.
Factory Cams
Sometimes, the factory cams leave a massive amount of performance gain ready to claim. The worst cams are in the L76 and L77. These were used in the VZ 6L, early VE 6L automatics and all 6L since the VE series II, including all VF 6L. These cams create very low valve lift and have short durations. The HSV LS3 and HSV LS2 cams are the best standard camshafts and improve performance when used in the other engines.
Any good upgrade camshaft will have a longer duration of valve opening events and create more valve lift. Depending on the combination, this will result in a different spread of torque across the rpm range. Some camshafts give more low-down torque than any standard cam, making more power everywhere in the rpm range. Some streetable cams create less torque until they go over 3600 rpm. After that, they gain much power, peaking at 6700 rpm. It is, ofcourse, possible to build LS engines with cams that rev to 7500rpm and, beyond that, make their torque and power even later.
Oztrack camshafts
We create camshafts with lobe shapes designed in-house using advanced software. We also work closely with our manufacturer during the development process. The exact lobe shape can be made using the latest CNC Camshaft Machine. We are continually improving our cam lobes and specifications using Prohub Dyno data. We can provide you with the results for all our camshafts. The data collected is on the same dyno and, for many cars, also the same exhaust, OTR and options.
When upgrading the cam in an LS engine, it is essential also to upgrade the valve springs. We recommend using dual valve springs. Sometimes, we opt for lighter spring kits with extra light titanium retainers on top of the springs. Using chromoly pushrods instead of the thin steel factory versions is essential. This change helps stabilize the valve, pushrod, rocker, and spring. We also use thicker chromoly pushrods for added strength. When upgrading the cam, it is advisable to remove the cylinder heads. This allows you to clean them properly and install new springs. It is also a good time to replace the lifters and lifter buckets. We have found that genuine LS7 lifters and their buckets provide excellent reliability. The lifters and lifter buckets will likely be worn on almost any engine, which is a great chance to refresh them.
When heads are removed, new gaskets and new head bolts are used.
At this stage, you can swap the heads for CNC Ported factory head design and get a modest gain in power, usually after 4000rpm. Shaving the heads and increasing compression is possible, but this can give away piston-to-valve clearance. Many bigger cams have no spare clearance to give away. It is wise to pay extra for new valve seats simultaneously. These parts are becoming a common and serious failure.
Aftermarket-designed heads are even better. Many give better “Piston to Valve” clearance and gain more solid power. But you pay a premium for these heads. We prefer the AFR260 cylinder heads for 6/6.2L LS3 and have made 453 rwkw from a 427 we built with them.
You can upgrade to a larger throttle body. However, if the hole in the intake manifold is not large enough to match, this upgrade will not be effective. In that case, it would be a waste of money. Upgrading the manifold is an option. There are several versions of FAST Manifolds for LS engines. Some versions perform very well, especially those used on LS1 and LS2 Cathedral Port Heads. The LS3, L98, L77, and L76 versions perform poorly unless paired with a larger throttle body. Additionally, they require an upgraded set of heads and a bigger camshaft to achieve optimal performance. On a small cam, this manifold/TB gives almost no gain.
It is recommended that the rocker trunion bearings be upgraded to a rocker bush we source from CHE—the CHE Rocker Bush Kit. The CHE rocker bush kit has been spintronic tested to 10000rpm and proven stable. They are much more reliable and smoother in movement. This may be due to less vertical friction, resulting in more power.
The factory harmonic balancer can be unreliable at high RPM. It is recommended that it be replaced with a 25% underdrive balancer kit. These give a small amount of extra power as well.
The other simple mandatory modifications for an effective cam upgrade are Performance Exhaust and OTR Cold Air Intake.
We recommend the VCM OTR kit and DPE Manta Exhaust.
This setup includes large 4-in-1 primaries that measure 1″7/8. It also has high-flow catalytic converters. Additionally, there is a choice between a twin 2.5″ or a twin 3″ catback exhaust system.
Performance Gains
A stock L77 engine standard often makes around 230 rwkw. A recent stock-cammed car made 267rwkw and 459Nm peak torque. A similar 6L with our LSV cam often makes around 327rwkw with peak torque near 538Nm. Our medium-size HP3 cam often makes 340-350 rwkw with peak torque near 550Nm. The biggest cam to suit stock pistons is the HPS, and with CNC factory heads in a 6L, they have made us as much as 378rwkw. A built race engine 6.0L with 12.:1 compression ratio and CNC Ported Heads made 400 rwkw using the HPX-R cam. With all camshafts, the LS3 often make around 13-17 rwkw more than the 6.0L.
See our Cam Packages installed at Oztrack
See Cam upgrade kit with remote tuning including autocal device. This kit is posted to you.
