I posted a thread earlier about XFI lobes vs. XER lobes, but I was confused. I meant XR vs. XER? The XER being the high lift cam. Some say anything over .550 lift doesnt gain anything in the 5.3L, and some say go with the big lift (.581). Just trying to make a descision. Price of valve springs is not a factor. I want to do it right one time and be done.

 

Sorry, I thought had lost your other thread...
Anyhow I've been told by Richard at wcch .550-.575 is the max with stock heads. I'd recomend giving him a call...

 

That would depend on which heads were stock for his truck, right? I'm thinking the 799/243 heads that were stock on a few 5.3's might take advantage of a little more lift, no?

 

Are you sure you don't mean XE vs. XER......

 

good point. When I asked Richard, I was talking about the 317 heads...

 

Well I don't think the 799/243s flow any better, about the same iirc.

 

http://www.compcams.com/Technical/Ca...obeCatalog.pdf