MyLS1Hauls

iTrader: (2)

So you're retarding the cam an extra degree above 5500? I have yet to mess with the upper end of the VVT table, but have decreased the amount of retard in the midrange by about half, and so far don't have any issues. You should be able to pick up some midrange tq gains by doing this. I also tamed down the corresponding VVT spark tables a bit, due to the now higher cylinder pressure.

MyLS1Hauls

iTrader: (2)

Retaining the VVT system will give you more power down low and more power up top, when compared to a non VVT setup...Advance the cam a bit down low and retard it a bit up top, and you will usually make more power. The key is finding out how much advance/retard works the best. The simplest way to start would be using engine sim software, and plug in different intake centerlines, to see how it moves the power around. Just have to be careful when installing an aftermarket cam, to be sure that there is no way the valves will hit the piston, regardless of the cam phaser position.

CalEditor@PCMCalibrators

iTrader: (4)

I disagree 100%. I feel it has to do with the last 3 on the list

Camshaft Position Actuator System Benefits

• Increased horsepower and torque
• Improved gas mileage
• Improved emissions
• Eliminates external EGR system

Valve overlap is the period when both the intake and the exhaust valve are open at the same time. With the exhaust valve closing delayed, the low intake manifold pressure (50-70 kpa) and exhaust back pressure cause exhaust gas to be drawn back into the combustion chamber.


When exhaust gas recirculation is not desired, the Camshaft Position Actuator System would advance the exhaust valve closing to 0 degrees. With the exhaust valve timing advance back to 0 degrees low engine speed operation is improved, most notably idle quality and throttle response. Advancing the exhaust valve closing reduces low speed lobe caused by valve overlap.




Variable Valve Timing
The camshaft position actuator used on the LY6, L76 and L92 engines is a vanetype actuator. This camshaft position actuator incorporates a 4x camshaft reluctor wheel. This camshaft position actuator has 60 degrees of crankshaft authority. This camshaft position actuator is in the home position when the actuator is fully advanced. This camshaft position actuator has 17 crank degrees of advance and 43 crank degrees of retard.

MyLS1Hauls

iTrader: (2)

So what exactly do you disagree with? That moving the ICL on the cam affects how/where the power comes on? That advancing the cam will bring the power on early, but fall off earlier. That retarding it allows better peak power?

We've all seen those diagrams from GM before. I'm fully aware of why they decided to implement cam phasing on these motors, and yes, the main reason was emissions, but it's not the ONLY reason. It does allow them to use a smaller cam, and still get decent peak power, by retarding all of the valve events up top.

I couldn't care less about the emissions/mileage benefit of the VVT system, but there are still other benefits to using it, even with an aftermarket cam.

CalEditor@PCMCalibrators

iTrader: (4)

I feel the reason for the VVT is to control Combustion Chamber Temperature.

A VVT engine will not out perform a non VVT engine on a dyno.
I have read several articles from cam manufactures that state the gains from VVT. The minimal gains are minor compared to the overall lose. I was schooled on VVT cams a few years back. I was under the impression you got the best of both sides. Thats just not they way it works. I have a feeling it was Greg Bannish that schooled me, but it might have been one of his proteges. I was dirrected to several articles.

If you put in a non VVT cam you will have more torque and horsepower. You just need to look at the big picture. Even with a VVT cam if you limit it you can gain. Yes you will lose also, but if you have mods then it could be a wash.

What happens if you have a higher stall converter? You can still PWM the converter to drop the RPM's down to a target. You still have the increased torque multiplier in the converter.

Monitor the Displayed Torque and HP on a datalog. Take a look at the numbers on a given trip.

Rhino79

iTrader: (7)

So you don't think a vvt cam of equal specs to a non vvt will make more under the curve power?

MyLS1Hauls

iTrader: (2)

This isn't VVT specific information...If you take a given cam and advance it by 4* from stright up, for example, it will pickup a bit of power below peak torque, but peak hp will be down. If you then retard it 4* from stright up, it will pickup power past peak torque. It is as simple as that. You might as well use the VVT system to do it, even if you only gain 10hp on the top end. You don't need some "special" VVT cam, it just has to have the proper amount of advance ground into it, to work with the cam phaser being used.

Bottom line is, if you know how to properly spec a cam grind, and tune it's VVT tables, the motor WILL absolutely make more overall power. It just isn't a disputable issue.

CalEditor@PCMCalibrators

iTrader: (4)

No you won't. Do some research

CalEditor@PCMCalibrators

iTrader: (4)

Please teach me how it works

Stock motor or built motor? Choose
Stock Converter only if you have a stock engine

Remember to make more power you need to extract more BTU's from the fuel

Rhino79

iTrader: (7)

How does an l99 camaro with 26 less flywheel HP and less flywheel tq at peak, run the and times stock as a ls3 m6 car. Effective gearing comparable, ls3 car is lighter. All else the same. It has a more aggresive cam and more compression. My guess would be because of average power, not peak.