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The cam degree was put in TDC, It's just a weekend cruiser not a race motor, i have some buddys with stroker 440's with alot more power and other Mopars with pretty much stock motors and they where installed TDC without advancing it and they run like a bat out of hell.
What am i missing on degreeing the cam for street use. Also any suggestions on who re-curves dist. in the Houston, TX. or surronding area's.
Thanks for all the imput, you guys have been alot
of help and carry the Mopar banner very well...
where the cam is installed at (intake centerline) has the major impact on where the intake valve closes, which is what determines cylinder pressure. cyl pressure determines torque for the most part.
for an XE274, it's ground with a 110 degree LSA, but with 4 degrees of advance built in, so if it was degreed in to verify intake centerline, it should be at 106 degrees after top dead center (ATDC). that puts the intake close point 63 degrees after bottom dead center (ABDC). compare to a comp XE268, which has the intake close point at 60 degrees ABDC.
now assuming you used the KB flat tops at 0 deck, 906 (usually 90-92cc) heads, and a thin MP head gasket, that yields a true compression ratio of ~8.8:1. using one of the online dynamic compression ratio calculators, and plugging these assumptions in, the dynamic compression of this motor end up being ~7.1:1...by advancing the cam 4 degrees, the DCR jumps up to 7.3:1....advancing the cam will move the powerband down in the RPM range, giving a boost in low end and midrange, and a slight cost in the top end (how much time do you spend at 5500-6000 RPM anyway?)
in essence, it'll make your XE274 behave a little more like the smaller XE268.
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