C. Lobe Separation Angle (LSA)


- LSA is defined as spread in camshaft degrees between the intake centerline and the exhaust centerline.

- Overlap is the number of crankshaft degrees that both the intake and exhaust valves are open as the cylinder transitions through the end of the exhaust stroke and into the intake stroke

- LSA is ground into the cam and cannot be changed without grinding a new cam

- Bigger duration cams will have more overlap then a smaller duration cam even if both are on the same LSA.

- The key to making overlap work is maximizing the power in the rpm band where you want it.

- Long overlap periods work best for high-rpm power. For the street, a long overlap period combined with long-duration profiles combine to kill low-speed torque

- Reducing overlap on a long-duration cam will often increase midrange torque at the expense of peak power, but if the average torque improves, that’s probably a change worth making.

- Many enthusiasts purchase a camshaft strictly on the basis of how it sounds. A cam with generous overlap creates that distinctive choppy idle that just sounds cool.

- While doing my research on the T1 I cam across this dyno in which if I recall Tony (Nineball) stated that the blue graph was a T1 (112 lsa) and the other 2 where a B1 (114) lsa. 112 vs. 114

- What really affects where the cam makes the most power is the intake timing events. What affects drivability most is the exhaust-closing event.

 

still a bit confused....had to read it a cuple times..lol....
low overlap,lond duration, mid lsa????

 

Wide lsa cams typically have lsa values of 113 and up. Narrow lsa would be 112 and down.

The wider the lsa, the less overlap. The narrower the lsa, the more overlap.

The more overlap a cam has, the rougher it will idle. If a cam has little to no overlap, it will most likely idle smooth.

A wide lsa cam raises the powerband and gives you broader torque curves, peak hp may be down slightly over a narrow lsa cam. A narrow lsa cam will have a "peaky" hp and tq curves. Narrow lsa cams tend to "Hit", where you'll start to feel it pulling real hard(usually around 3000-4000 rpm).

 

wat if i just do all that to an 8.1???????????
just thinking bout it...i know i read bout a truck just like mine with an 8.1 years ago be4 the 6.0 was the "cool" thing to do...lol and that thing was a TQ monster!!

 

Your truck is already set up for a 6.0. An 8.1l swap would take a good amount of time and parts, whereas the 6.0 bolts in. If you want a torque monster, you can just take your future 6.0 and stroke it to 402-408ci. That's what I plan on doing to my 6.0 if it ever blows.

 

i see......i wouldnt mind doing that but it would cost a bit more than wat i have pland to spend.....