Educate me on cams

RedFox5.0

New Member
Apr 3, 2007
16
0
0
PA
What are the biggest cams I can put in my 4.6L (NPI, but maybe I will get PI Heads) without causing any problems? What are these "stages" e.g. "Stage 2 Cams" and what cams work good for these 4.6L's? Thanks.
 
  • Sponsors (?)


Ho jeez. Well, ask yourself first why you're getting cams. Getting a stage two cam or "biggest cams i can put in my 4.6" with NPI heads and intake manifold is at the least illogical.
Look into comp cam xe268H's for you NPI heads and consider a pi intake manifold!

If PI heads and intake then cams make more sense considering the gains from cams are up top in the rpms where air flow restriction hurts the hardest.

Then look into xe262ah's or CMS stage 1's. If you're bold and you will degree the cams perfect, CMS stage 2's (XE270ah's may not have enough piston clearance). Even then a ported PI head makes sence.

Are you doing it for the sound?
 
Ho jeez. Well, ask yourself first why you're getting cams. Getting a stage two cam or "biggest cams i can put in my 4.6" with NPI heads and intake manifold is at the least illogical.
Look into comp cam xe268H's for you NPI heads and consider a pi intake manifold!

If PI heads and intake then cams make more sense considering the gains from cams are up top in the rpms where air flow restriction hurts the hardest.

Then look into xe262ah's or CMS stage 1's. If you're bold and you will degree the cams perfect, CMS stage 2's (XE270ah's may not have enough piston clearance). Even then a ported PI head makes sence.

Are you doing it for the sound?

Sound never hurts but I was doing it mostly for better performance at the strip.
 
can you elborate on this for me?
I don't really know what he's talking about there. Cuz there's stage 1-3 or 4 NA cams and 1-3 blower cams. So if you're staying NA go what ever you want, if you're going to go blown then a VT stage 1 cam works pretty weel for NA and blown, but a blower cam in a NA car works great as well for in the meantime.

If you want performance at the strip a cam isn't where you should start. As I said it's top end/high rpm power. You don't have any high rpm breathing so that wont help too much. I'd say install a PI intake manifold and some pi cams or xe268h's which is a stage 1 NPI head cam.

Or put on PI heads (or port your NPI's) and put on a PI intake with stage 1 CMS or comp cams, or stage 2 CMS's
 
Don't pay attention to "stages" because each company has different specs for each. I agree with the info above. Here are basics

Some things to look at are lift, duration, and lsa. Lsa is lobe separation where most N/A cams are 108-112 and s/c, turbo cams are 114-116. More lift generally improves power in the middle of the rpm range. Duration at .050" lift (the number of degrees from the time opens at .050" lift until it hits .050" before close) determines rpm range, where the more duration extends the rpm range. Duration at .050" lift and lsa determine lope or sound. These aspects along with things like lobe centerline determine how big of cams you can get.

I'd suggest something with around a .550" lift like comp262's or Cushman motorsports "stage 1". Once you get more mods like intake, exhaust, and ported heads the more duration you'll need