Rhino79

iTrader: (7)

I think that with stock heads, intake, and TB, with a good cat-less full exhaust a NA motor would probably be better suited with a single pattern cam with a 112 LSA. And with stock heads, intake, and TB, with a more restricted exhaust it may be better to use a dual pattern cam on a 112-114 LSA.

budhayes3

iTrader: (19)

What confuses me is the contradiction between the overlap issue (more overlap=more top end power with weaker bottom, and tight lsa increases overlap) and the last statement that "Narrow LSAs tend to increase midrange torque and result in faster reving engines, while wide LSAs result in wider power bands and more peak torque at the price of somewhat lazier initial response." There has to be a fine line where intake duration becomes a major player...

Rhino79

iTrader: (7)

Well, Overlap is actually a combination of duration, lift, and lsa, not just lsa. And for their comment on Narrow lsa's producing more midrange, I think they are comparing 2 cams with identical duration and lift. For example like the TR224 on a 112 or 114. The 112 will produce more midrange, be very lopey, but its power will be in a more narrow range (ex:2500-6500), where the 114 would make less midrange torque, but idle smoother, and make power over a wider range (ex:2000-6500). I don't know if that would be the exact power bands of the 224, but I am just trying to use it for examples. The 114 may make its power over a wider range, but the 112 will make more power (in a more narrow range) and be more responsive.

budhayes3

iTrader: (19)

So I guess it comes down to where one variable has the greatest affect. With 2 cams being equal (same lift and duration), one on a 112 and one on a 114, the 112 cam will have more overlap, but since the narrower lsa should increase the mid-range torque, I'm assuming that would cancel out the effect of the increased overlap.

Rhino79

iTrader: (7)

I think so, the way I see it is that the 112 will put out a little more power but in a more concentrated range, and the 114 will make less power over a wider range. I guess it still just comes down to what you are want to do. Some 4x4 guys might like the 114 because of the wider range and some 2wd guys might like the 112 if they don't pull or care to lose a litlle bottom end. Personally I would sacrafice a little on bottom to go with the 112 because I would like power for the street and strip, and in 1/4 mile racing, how much time do you actually spend below 3000 rpm's when you have a 3000 converter? That is what I would be going for, but everyone has their own needs.

Rhino79

iTrader: (7)

Man, the last few days has been hardcore cam questions! I, like everyone else always wondered these same questions. Maybe before too long we will all know a little about cam selection.

budhayes3

iTrader: (19)

Makes sense...now throw a converter into the mix and there goes one's worries about a soggy bottom. Plus, FWIW, the 112 will sound meaner (if that's a concern)

Sorry if I took your thread and ran with it LoudAzzLoStepside, I have alot of the same questions and concerns that you do...maybe some of this info will help you out too

Thanks Rhino

budhayes3

iTrader: (19)

Rhino79

iTrader: (7)

No Problem.

StrokerAce03

iTrader: (7)

This is a great thread as I'm starting to learn a little more about cams. When does the displacement come in to play as I know a 6.0 can handle a bigger cam easier than a 4.8/5.3? What are the numbers at which you are over camming an engine? I feel like I'm hijacking but I know LoudAzz is running a 5.3, which would make his cam different than my 4.8 or a 6.0 for that matter. I guess its hard to choose the perfect cam due to the individual's variables on what they are running or are going to run. Glad to see some people doing research on this instead of just slapping a "big 'un" in there and seeing what it'll do.