What is a good lobe separation?

Some engine specialists refer to it as that 106 sound—the NASCAR and short track oval sound where preferred lobe separation is usually specified between 104 and 106 degrees. The primary function of narrow lobe separation is to impel urgent acceleration off the turns when the throttle is opened.

Does lower LSA mean more chop?

While it’s true that the LSA plays a big part in this, the duration of the cam also contributes. The higher the duration, generally the choppier the idle is. Typically the higher the duration, the closer the LSA is too, but not always.

Does LSA matter?

LSA doesn’t really matter in the scheme of things, its just a result of the valve events. my $. 02, However a cam that had 108 LSA could be very driveable, make lot of torque.

What is lobe separation angle?

What Is Lobe-Separation Angle? LSA is the distance from the centerline of the intake lobe to the centerline of exhaust lobe. It is the average centerline between both lobes and expressed in degrees ranging from 95 on the extremely narrow/tight side to upward of 120 on the wide end.

What does higher lobe separation mean?

“On a naturally aspirated engine, the lobe separation angle has an effect on whether the engine reaches peak torque a little earlier or later in the rpm range. Typically, narrower lobe separation develops peak torque at lower rpm and widening the separation tends to build peak torque higher in the rpm range.

How do I check my lobe separation?

To check your LSA you calculate it by adding the intake and exhaust Lobe Centerline figures together and dividing their sum by two (Ex: 112 intake Centerline + 116 exhaust Centerline = 228 / 2 = 114-degree LOBE SEPARATION ANGLE).

How does LSA affect performance?

A wide LSA reduces valve overlap, softens the idle and improves overall drivability–especially on the street where performance engines benefit from 112 to 114 LSA. Nitrous engines, which make plenty of power and torque, often run wide lobe separation angles to moderate cylinder pressures and temperatures.

What is the difference between 114 LSA and 112 LSA?

A wider LSA figure (i.e. 114) moves the lobe centerlines further apart and will smooth your idle due to the decrease in overlap that it creates. The lower the figure (i.e. 112) moves the centerlines closer and will increase bottom end power, but your idle will suffer along with it.

What makes a cam sound lopey?

cams lope because of events, they open valves because of events, they do it at certain times because they are events. The smaller the lsa the larger the chance for overlap. If you have two cams, same everything, except for lsa, the one with the smaller lsa will have more overlap…

What does more lobe separation do?

How do I find my intake centerline?

To find the intake lobe centerline, divide the intake duration by two and subtract the indicated intake opening point as shown in our example with the Comp XE274 example. Sometimes you find a very mild or stock cam where the IO occurs after TDC (ATDC). In this case just add the IO figure to one half of the duration.

How is the lobe separation angle of a camshaft chosen?

Selecting a camshaft for a given engine’s purpose usually involves a compromise between low- or high-end power options, and the lobe separation angle (LSA) is one of those factors where engine builders have to make a choice between those priorities.

What is the separation angle between intake and exhaust?

“The lobe separation angle is the angle in camshaft degrees between the maximum lift points, or centerlines, of the intake and exhaust lobes,” says Eric Bolander of Erson Cams. “It affects the amount of valve overlap; that is the brief period of time when both the intake and exhaust valves are open.”.

How does the lobe separation angle affect the power curve?

A narrow, more specific power band is also a product of a narrow LSA, as is a lumpy idle quality–often referred to as the 106 sound. “The tighter the lobe separation angle, the peakier the power curve will be,” confirms Bolander. “It produces peak torque earlier—coming on quicker and stronger—but also it falls off quicker too.

What is the LSA of a crankshaft?

According to the Comp Cams catalog, “The lobe separation angle (LSA) is equal to 1/2 the angle in crankshaft degrees of rotation between the maximum exhaust valve lift and maximum intake lift.”