.560/.575 lift, 225/235 .050" duration, 108 LSA

thats the cam specs...what does 108 LSA mean?

 

lobe separation angle. the angle in degrees that the lobes of the exhaust and intake are split by. It along with the duration will tell you the approximate overlap.

On NA motors a shorter LSA and longer duration (to a point) helps shove the powerband up the RPM range and can increase HP usually at the cost of tq somewhere in the curve.

On blower/turbo motors a wide LSA helps reduce boost loss through the exhaust and increases power that way. They also tend to favor the exhaust side since the incoming air is pressurized.

Go to howstuffworks.com and look up camshaft

That cam has a lot of lift... check PTV clearance.

 

yes your right about the VT cam, thats what im putting in me engine when i get back from iraq. How do you find out the "centerline" what is that?

 

Centerline is when both valves are closed.

 

so what is the centerline of the cam i named above? Its the VT Stage 2 N/A cam.

 

When cam companies are referring to centerline they use intake centerline as this reference point. The intake centerline is expressed as the number of degrees ATDC. Generally, the intake centerline will be between 104 and 116 degrees ATDC. You need to look at your cam timing card to see what the centerline on this particular cam is. I tried looking it up but couldn't find it. I believe that the VT cams are not ground advanced so if you follow the standard timing procedure you shouldn't need to degree in your cams.

Look here for more info.

http://www.modulardepot.com/?show=articlesdet&aid=39

 

You can call up VT and ask... they'll know for sure.

 

The cam card for my VT Stage II said to degree to 108.5. Any cam you buy should come with a cam card, assuming you buy it new from a company and not some used set from an individual, and it would have that information on it your specific set of cams.

Scott