cams?!

[DV2000NJ]

Long day, I meant Seven but my hands were going faster than my brain...

Ah okay. I get it now.

You had me looking through the whole thread to figure out who the hell Steven was.

 

[Texas1911]

yes i got the 5.3, my bad for leaving that out. i don't really understand how cams work.....i just know they make your motor go....lumplumplump vrooom vrooom! thanks for the info, i'll write it down in my book of "things for my truck to buy when i don't have bills"

Cams regulate the timing moments for the valves and are one of the most important parts of the entire engine.

Duration is the 3-digit numbers, expressed in degrees, that tell you how long the particular valve (intake or exhaust) is open. In the domestic world the cams are often expressed at 0.050" of lift, which is a more realistic figure than what is known as "advertised duration". It's more realistic because the valve does not flow significant amounts of air until it reaches a critical lift amount, and 0.050" is generally regarded as the point.

Lift is expressed in inches (or metric), for example 0.320", which gives you the lift at the cam. The actual valve lift is the cam lobe lift times the rocker ratio. If you go with too tall of a lift you can shove the valve into the piston. Cam manufacturers will warn you when you need to fly-cut the pistons for most common applications.

LSA, or lobe seperation angle, is the measure in degrees between the centerlines (the middle of the lobe, it's peak) of the intake and exhaust cam. A tight centerline, lower number, is good for highly tuned engines where the exhaust and intake setups are tuned to maximize pulse tuning. On anything but a purpose built engine you want to shy away from a really tight LSA as this will give you alot of overlap, and a shitty idle, along with generally poor low end mixture quality (read: no low end). A moderate overlap, paired with a good set of headers, will give you a really nice gain.

Lobe profiles are set to work in conjunction with certain valve spring setups and valvetrain designs. You'll want to stick with something that isn't very aggressive to keep your OEM valvetrain happy. Upgrading your valve springs, even on motors that don't exhibit significant float, can net you a few HP on the top end by improving valve harmonic control.

The worst mistake you can make is over-camming the motor.

Be glad you have cheap cam options. The cheapest cams for my motor are $1200, and that's before I go replacing 24 valve springs. Needless to say, stock cams are OK for me.

I recommend having the truck re-tuned after a cam swap since the ignition timing moments on an engine that has had a big volumetric efficiency shift aren't optimal. I'm sure the Bear people can help you out with that. Usually this is one reason why people report lackluster gains and poor low-end with cams.

 

[svensk]

yes i got the 5.3, my bad for leaving that out. i don't really understand how cams work.....i just know they make your motor go....lumplumplump vrooom vrooom! thanks for the info, i'll write it down in my book of "things for my truck to buy when i don't have bills"

I'm sure the Bear people can help you out with that. .

 

[JennaBear]

 

[sand man]

The 220 is a good cam Faisal. Your truck has a 5.3 right?

yeah 5.3

 

[LMSeven]

The 220 is a good cam Faisal. Your truck has a 5.3 right?

yeah 5.3

You'll be happy with it probably. Might want to look into a converter tho. TSP also makes a few 220 cams with different lifts.

 

[Texas1911]

I was unsure of your company name at the time. Meds make you do crazy things... like typing out elongated replies because you have nothing better to do.

 

[svensk]

I just thought it was funny after typing up that epic post.

 

[Bigredmariner]

I just thought it was funny after typing up that epic post.

Yeah he said Epic.

 

[JennaBear]

I was unsure of your company name at the time. Meds make you do crazy things... like typing out elongated replies because you have nothing better to do.

No worries!