What is a good camshaft duration?
Cams with durations in the 195 to 210 degree range (measured at . 050˝ cam lift) are usually considered best for stock unmodified engines and those with computerized engine controls. A cam with a duration of 240 degrees of higher will typically produce the most power from 3,500 to 7,000 rpm.
How often do camshafts need to be replaced?
When to replace the cam belt It’ll usually need to be replaced more than once over the course of a vehicle’s lifetime. Manufacturers will usually recommend to replace your timing belt after a set number of years or miles. This could be anywhere from 40,000 to 100,000 miles or 4+ years.
What does a long duration cam do?
When someone talks about a “big” cam, they are referring to cams with longer duration. This keeps the valves open longer, increasing midrange and top-end power at the expense of low-end torque. A shorter duration cam does just the opposite.
How is cam degree calculated?
D.C. To determine the amount the camshaft is advanced in crankshaft degrees, simply subtract the difference between the intake and exhaust Top Timing and divide by two. In this case 37° – 29° = 8° ÷ 2 = 4 crankshaft degrees of advance.
What makes a camshaft 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 is considered a mild cam?
An RV or towing camshaft, which is considered a mild performance or an economy cam, will often have a narrower LSA, between 112 and 114 degrees. Hot street camshafts usually have 110- to 112-degree LSA, while high performance and racing camshafts will often run between 105 and 108 degrees.
How much is a cam replacement?
Camshaft Replacement Cost – RepairPal Estimate. Labor costs are estimated between $850 and $1,072 while parts are priced at $459. This range does not include taxes and fees, and does not factor in your specific vehicle or unique location. Related repairs may also be needed.
Is it worth replacing camshaft?
The camshaft opens and closes valves in the cylinder head. As the camshaft rotates, high spots on the cams press on valve lifters. That motion forces valves to open, and valve springs return the valve to the seated position as soon as the cam lobe rotates past. But what makes the camshaft rotate, you might ask?
Which is better cam or lift or duration?
When comparing two different cams, if both profiles rate the advertised duration at the same lift, the cam with the shorter advertised duration in comparison to the 0.050 duration has more aggressive rmp. Conversely, running too big a cam with too low a compression ratio leads to sluggish response below 3,000 rpm.
What is considered a lot of cam overlap?
To maintain sufficient idle and vacuum qualities, the cam tech recommends the cam be ground on, say, 112-degree LCA, which gives an overlap of 66 degrees. For a typical performance-headed 350, the optimal LCA is usually 108 degrees.
What is advanced cam timing?
A Basic Overview of Cam Timing To advance or retard a camshaft is to change the alignment between the camshaft and the crankshaft. Advancing or retarding the cam pushes the centerline of the camshaft to one side or the other of the crankshaft centerline.
What is cam rpm range?
Definition & Description. The basic operating rpm range for a camshaft is its “sweet spot.” This range is where the engine will produce the most Torque and Horsepower.
What does the duration of a big cam mean?
Duration is how long the valve is off its seat. It is listed in degrees of crankshaft rotation. When someone refers to a “big cam,” they mean it has longer duration, not higher Lift. Manufacturers often list 2 different duration values:
What does it mean when a camshaft has a longer duration?
When someone refers to a “big cam,” they mean it has longer duration, not higher Lift. Manufacturers often list 2 different duration values: Advertised Duration is the degrees of crankshaft rotation that the lifter is raised more than a predetermined amount.
What’s the advertised length of a camshaft lobe?
Let’s say this numbers ends up being 270 degrees. This is the “advertised” duration of the lobe, because this is the number that most camshaft manufacturers use when referring to their camshaft duration numbers in advertising. Common camshaft terminology explained.
Where did the term advertised duration come from?
What originated as seat-to-seat duration is now known as”Advertised Duration” , i.e. you really don’t know how it was measured. Besides, it makes more sense to use numbers at a higher lift, where the valve is open enough to have significant flow.