LS Cam Upgrades Explained - The Benefits, the choices, the process.
Upgrading the factory camshaft is a great way to gain more power and torque. It's usually the next step after improving exhaust and the cold air intake.
Gains are reliable even when using very small camshafts. The increases are below:
LS1 - 20-50 rwkw
LS2 - 20-40 rwkw
L98/L77/L76 - 30-70 rwkw
LS3 - 20-40 rwkw
LSA - 20-40 rwkw
The numbers below are above what a tuned car with the stock cam and full exhaust upgrade would typically get.
When upgrading from a stock car, the gains are much higher, and on some models, the gains above stock (exh-OTR cold air- tune-cam) can be as much as 120 rwkw.
We have developed the parts we offer over the past 10 years to be the best available for the purpose.
Cam upgrades include the following parts:
Dual Valve Springs with Light Retainers- Chromoly or Titanium.
LS7 Lifter guide trays
Dual valve springs give insurance in the case of one spring breaking.
Chromoly pushrods give drivetrain stability and don't induce valve float at high rpm like the factory pushrods would.
Hydraulic Lifters are the Achilles heel of the LS engines and statistically, we have found the genuine (not replica) LS7 lifters the best. Often lifter failures of the wheel are more oil related. But often the lifter is the first point of failure. So it is worth changing them to new ones every chance you get.
The lifter guide trays can also wear and allow lifter vibration so we choose to replace them as well.
The factory camshafts are designed for use with the standard exhaust and intake & are built to help emissions.
They have maximum valve lifts of between 467 and 551 thousand of an inch.
The best factory camshafts are in the LS3 6.2L, but there is still plenty of performance to be gained in the LS3.
Factory Cam Specs are below
196/201 0.467"/0.479" 116
200/208 0.478" 116.5
6.0L LS2 HSV
204/211 0.525"/0.525" 117.5
6.2L LS3 cam specs are near
204/211 0.551/0.525 117
High-Performance cams with street-able reliability in mind usually have between 0.560 and 0.630 lift which provides bigger "gulps" of air during each valve event into and out of the cylinders.
Oztrack's current custom cam offering is below.
Most high-performance street cams will have at least 212 degrees duration (measured at 50 thou lift) and may even have up into the 240s duration. Cams of long duration gives much higher magnitude "gulps" of air when combined with the extra lift.
Camshafts are designed to precisely time to opening and the closing of intake and exhaust valves: this timing effects power output, rpm range, and idle quality.
If the intake valve opens early when the exhaust valve is about to shut, this helps drag extra air into the cylinders which can then be matched with extra fuel to make more power. This effect is called "overlap."
At idle there is a side effect of overlap, and that is contamination of the intake air with exhaust gas. The result is a choppy or lumpy idle. Undesirable in a factory car but usually admired by performance enthusiasts.
Streetable cams usually range from very mild and close to stock idle to as big as can fit in the engine.
Small cams usually have minimal overlap and 50 thou durations in the 210 to 225 range.
Mild cams 225 to 235
Big cams for a street car are above 235.
Small cams often make similar peak torque to bigger cams. They can also often beat them on a dyno until above 4000rpm. Mild cams often challenge the big cams to beyond 5500rpm.
Even small performance cams will make peak power 500rpm higher than the factory cam and can sometimes beat them for torque from as early as 1200rpm.
The radiator, harmonic balancer & front timing cover are removed. To create the space to pull the camshaft out.
It is also best to always take the opportunity to install new lifters, so the heads need to be removed first since the lifters are underneath. Once the heads are on the bench, it makes installing valve springs easier.
It is an excellent opportunity to clean the carbon buildup off the tops of the pistons and the combustion chambers in the cylinder heads..
Once the heads are back on the block, and the cam installed. It is essential to check lifter pre-load to make sure the pushrods are the correct length. The right Pre-load of lifters is critical and can minimize valve train noise. There is always some extra noise though.
Once the mechanical work is complete, it is best to have a tune flashed to suit the mods, and the engine started and checked. Plus coolant & oil levels topped up and corrected. Then the car can be tuned.
Most installers have done this job many times, and it is usually a 3-5 day booking.
Get more information about our drive in-drive out cam upgrade packages offered at Oztrack via messenger.
See our range of postal cam upgrade kits