What cam to use in a 318
with that rear ratio and stall speed, I think an XE268 would be a little big. personally, I'd probably stick with something that has a duration more like and XE256 or XE262. I ran a hydraulic roller in my '85 block with magnum heads that had .320" lobe lift (.512 calculated valve lift with 1.6 rockers) without issue. I had my stock roller cam reground by bullet cams. in their flat tappet lobes, I'd look at something like their HC260/296 lobe on the intake and their HC270/312on the exhaust....I am not a fan of lumpy idles, so I'd probably do it on a 112ish LSA, but install it at 106 ICL.
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