bfhawki

I have a cam for sale that might work for you.

Comp Cam 228/232 .588/.595 111+1 It is on the XE-R lobes. It only has 600 miles on it. The only reason I took it out was that at idle, it shook the whole car. The idle sounds great and it really pulls. Predator says it is one of his favorite street/ strip cams.

My car made 431 rwhp and 400 rwtq with this cam, PRC 5.3L heads, headers, and all the bolt ons except 90/90 setup. Dyno graph is over in the dyno section under the title: PRC Stage 2.5 5.3L Heads 228 camshaft results. It was posted by Jason 98 TA , co owner of Texas Speed.

Asmodeus

Playing with a DCR calculator, I put in my 228/232 numbers. Got my DCR at 8.4 to 1 with 65cc chambers. However, going with a smaller intake lobe, and dropping it to a 216/232, my DCR went up to 8.8 to 1. Now tell me, which is going to make more power? The smaller intake lobe with the lower DCR, or the bigger intake lobe with the lower DCR? The trend shows that with a fixed SCR, a smaller cam will always make more DCR with the same LSA and advance. I'm just trying to understand this. So, a cam with bigger lobes to make DCR is always going to need a tighter LSA and more compression?

N4cer

iTrader: (11)

NEED? No. But it will benefit from it across the board. The bigger cam will be better on the top end, regardless. DCR isn't the end-all of power. But it is the often overlooked component that makes idiots say that big cams don't drive good, and don't have much low end, and also makes people wonder why they didn't get enough guts out of their setup.

But yes, with earlier IVC, you're getting more DCR. Great if you race people at 2500 rpms. But with the same DCR on a bigger cam, you've got it everywhere.

Asmodeus

ok, so.. a smaller lobe is going to have an earlier ivc on the same icl I understand that. a bigger lobe can have an earlier ivc with a lower icl. but with that situation, you're creating more overlap. And with more overlap, you're getting more dirty air on the intake downstroke. At least until the point where the rpm's and scavenging are efficient enough to continue to draw air through the cylinder into the exhaust tube, correct? so how does the effect a big cam on the low end? is it better for it to have correct VE's? focus on cylinder fill? a high DCR? It doesn't seem like DCR is as concerned with cylinder fill as it is the upstroke..

I don't even know what I'm asking heh, I think I just need to read a book on it.

N4cer

iTrader: (11)

LOL yeah. I mean, "correct VEs". For what goal? The VE's determine where the powerband lies, and how it carries out, so your goal is important for deciding what your VEs need to be. Other than that, you carried that way beyond me.

cws T/A

iTrader: (3)

It will require more static compression the later the ivc closes , it doesnt have to have a tight lsa . I still dont get the huge cams in stock scr engines. The torque shows it on the dyno graphs When the actuall cam company that cuts it requires a higher staic compression to make full use of it . A 110 lsa is a common N/A gen 1 sbc LCA. Hell my 244@.050 cam off the shelf had a 106 lsa . It run dam good .

Bink

your 244 closed @ 48*ABDC@ .050 and 73.5* @ .006".
The key I would guess is the overlap of 32*/.050 and 62*/.006" - cylinder filling.
FWIW.