I think back 25 years ago when I was mud racing in street stock classes and we had to pull a certain amount of vaccum at idle to make the class it seems like 230 duration @.50 was about the most we could get away with on old school small blocks.I've narrowed it down to 3 possible
1. Summit Stage 2 Truck cam:
218/227 duration, 0.523"/0.524" lift, and 112 LSA
2. Elgin "Sloppy Stage 1" (or Stage 1.5 depending on who you ask) 1839-P
220/224 duration, 0.575"/0.575" lift, and 112 LSA
3. Elgin Sloppy Stage 2 1840-P
228/230 duration, 0.585"/0.585" lift, and 112 LSA
The summit cam is winning in my head currently although the Elgin Sloppy Stage 1 is very close to it. Closer duration split but higher lift. It's probably a wash power wise but the Summit may have a tamer lobe design that's better for long term valve train reliability. However, not that that really matters as I'd never see the kind of miles where it would make a difference. Both cams have stronger bottom ends with gains up to 6500rpm.
The Sloppy Stage 2 is interesting to me as it's now the default cam for most budget LS stuff. It supposedly gains power everywhere including the bottom end but I have seen some conflicting reviews of the bottom end gains. This is a graph right from Sloppy Mechanics from a stock 4.8 and it gained 102hp while still gaining slightly down low and that's on a the smaller 4.8! I'd think the 5.3 with the longer stroke would be better down low.
The tradeoffs are that idle would be a bit rougher and could be slightly harder to tune but there's plenty of people on the internet that have tuned this cam to behave pretty well.
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It seems like that's the range for a good all around LS build now too?
I'm trying to read up all I can right now on engine builds like yours. I've got an 2005 6.0 for my k-30 that I have waiting for new cam.
So would you be running a better spring with any or all of your cam choices?
