how to determine power band of a cam?

[redbird00]

exactly what it says, how is one supposed to figure out their power band on a custom ground cam? i'm looking at getting a cam in the fall... i want to do p&p heads, both intakes, and tb while its all out... 3.42's with a 2800 stall converter, a good power band would be from about 2500-6000 right? how would i figure out what kinda cam i need? thanks...

merlin

[Bliggida]

Merlin there is a very good chance, we may be doing this together!!! Lets chat at Sonic, got some ideas for the cam.

[Tiago]

mainly the powerband is dictated by duration, the more duration the higher up it goes, of course there are oteher factors but that is a biggy.

[nino]

i still would like to know how to tell the powerband. when i got my cam, magnus asked me where my powerband was and my answer was "duh, i dont know, i just hit the gas and go"

good question redbird, too bad nobody is answering it.

[Bliggida]

Really, its dictated by a dyno run. You just run your car up as safe as it will go, and see what the dyno results show you. If your HP drops off at 5700 there is no reason to rev any higher. Set your limiter for 5800 and be done with it.

Thats the jest of it, there are many other factors but that is the general idea.

[Arctc Wolf]

the powerband is determined by the ammount of overlap ur cam has. overlap is the time when both the intake and exhaust valves are open at the same time. the more overlap it has, the higher up the powerband will be. the less overlap, the lower the powerband will be.

The 2 things that affect overlap are duration and lobe separation. lobe separation has the biggest effect. smaller lobe separation, more overlap. bigger lobe separation, less overlap. Next, lengthening duration w/o increasing lobe separation will increase overlap. shortening duration w/o shortening lobe separation will decrease overlap.

many people think less overlap makes their cam's peaky, when in reality, the Intake centerline is what makes it peaky or broad. if you increase cam timing(meaning u increase the intake centerline), then the powerband will be more peaky, retarding cam timing will make the powerband more broad.

Hope this helps

[nino]

when i was gettting my power pack, tom had certain cam specs for me already, then he emailed me and asked if i wouldnt mind trying a different spec cam. he said it ws for less overlap.

[redbird00]

ok i think i got it, i had to read it about 34529 times...

ok i'm looking at a

216/216 .520"/.520" 112LSA 110IC

ok it has a higher duration but a lower lobe seperation to keep the powerband where it needs to be... good lifts, all around good NA imo, what would be the benefits(if any) of making it

216/216 .520"/.520" 110LSA 108IC

a little lower lobe sep. and ic, so it would move the power band up a little... and this goes back to my original question, how am i supposed to know what rpm range im in with either of these cams...

lets look at comp cams new cams...
Xtreme energy 3800v6...
192/200 .480"/.496" 110LSA - 800-4800
200/206 .496"/.480" 112LSA - 1000-5500<-
210/220 .512"/.512" 115LSA - 1000-5500

high energy for the buiick gn v6...
212/212 .504"/.504" 110LSA - 1200-5800<-

so raising the duration and lowering the lobe sep. only changed the rpm range by 200 and 300 respectively. so by raising the duration to
216/216 and leave the lobe sep. the same, then the rpm range will only change a little bit... say something like 1300-6000 so what about

220/220 .520"/.520" 110LSA 108IC

i think that that cam will give me the power band, i.e. 1400-6100 that i want... any one else's input would be greatly appreciated... thanks...

merlin

p.s. damn that was a long post... and that cam is frickin huge!!!

[ April 15, 2003: Message edited by: redbird00 ]</p>

[nino]

1400-6100 powerband????

quoted from duece bigs "that btch is huge"

[Tyler]

buy it, dyno it. let us know! [img]smile.gif[/img]

im looking for a good cam for NA!

i have NO IDEA what would be great for more of a topend pull. like.. from 1300 to bout 6k

[Arctc Wolf]

if ur having heads done, add more lift.

[StockV6Cam]

<blockquote>quote:</font><hr>Originally posted by Tyler:
i have NO IDEA what would be great for more of a topend pull. like.. from 1300 to bout 6k<hr></blockquote>

Ummm dude, from 1300 to 6k IS your powerband. Below 1300 is called IDLING. Your topend could be considered 4500-6000 rpm.

[SLOWBRAEATER]

<blockquote>quote:</font><hr>Originally posted by nino:
1400-6100 powerband????

quoted from duece bigs "that btch is huge"<hr></blockquote>

actually the guy says "Thats a huge bit**" [img]tongue.gif[/img]

[nino]

well i hope i got my point across with that being a powerband---"Thats a huge bit**"

[Tyler]

ok so what if its my powerband.. right now its bull****!

i prolly dont even see 170rwhp. i doubt even 160.

i want the same powerband.. but lots more power..

get my drift!?