What is more informative when selecting a cam?

[Stang_1973]

Should I look at Adv. Duration or Duration at .500? As for lift, how high is too high? How do you know what is too big for a stock stall converter?

The car is my daily driver but I would like to have more power fo rth e street and maybe go to the track once in a while.

 

[VictorII]

Should I look at Adv. Duration or Duration at .500? As for lift, how high is too high? How do you know what is too big for a stock stall converter?

The car is my daily driver but I would like to have more power fo rth e street and maybe go to the track once in a while.

Look at duration at .050. Advertised duration is all over the place. Access your true needs and mods, and then call a manufacturer or two or Jegs tech lines to get advice. Know your rear end ratio and whether it is Tractionlock or open. Off the top of my head, a Performer type grind is great for an otherwise stock or almost stock engine. My engine is not at all stock, but I run a Performer type grind because I like smooth idle. Be ready to tell them what kind of valve springs you have. To much lift on stock springs will result in bind or breakage. Not good. A spread duration, like on the Performer is good. Lets the exhaust out more efficiently.

 

[tjm73]

Cams can be tricky. Go to www.compcams.com and review/learn as much as you can.

For a daily driver something with less than .530" lift, 112 or more duration and 224 degreess or duration at .050" (or less) would be a decent cam. But cam needs vary depending on the setup of the engine the gearing and such.

I'd recommend you call a cam company and ask them what info they need to recommend a cam for your application.

 

[ratio411]

Duration @ .050" is the only way to compare. "Advertised" is done at the discresion of the maker and they all measure differently to market their cams.

Read all you can, like mentioned above, Comp and Lunati have in depth info in their catalogs... The also have example scenarios with different engines, describing what cam specs would be used for the scenario and why.
They use Chevy engines of course, but you get the jist of their reasoning on displacement, weight, gears, use, and even nitrous.

Another thing to remember, 'house' cams at Summit, Jegs, even Edelbrock are often made by a mass producing supplier with a variety of generic grind specs.
The 3 I listed above all receive their cams from TRW.
TRW has a couple of specs it churns out and then the middleman boxes them up with their name on them.
Check TRW's specs and compare to Summit house cams and the Edelbrock cams...
They are all the same specs. So if you really like one of Edelbrock's over hyped grinds, get it from TRW or Summit for half the price.
I think PAW uses TRW cams too.
Something to consider.
Dave

 

[ratio411]

One more topic...
LCA
When you look at cam specs you generally see duration, lift, and LCA.
LCA is all about overlap.
The lower the number (106, 108), the more overlap is ground into the cam.
Higher numbers have less overlap (112, 114), and have a profound affect on your engine's character.
Lower LCAs are most compatible with higher compression ratios, standard trannys, and the love of lope.
Higher LCAs are used in nitrous applications, low stall auto trannys, masking lope and creating vacuum.
The industry standard and happy medium is 110...
The reason higher LCAs are not compatible with moderate to high compression ratios is because they don't allow the engine to regulate cylinder pressures well. So they can become detonation prone. More overlap allows higher compression on lesser octane because excess cylinder pressure is not trapped.
IMO, street engines should use 110 LCA with auto tranny, 106 or 108 with manual. Nitrous should use 112 if the gas is applied often.
Dave