|02-04-2013 05:01 PM|
Cam was a Crane hydraulic roller p/n 119831, duration 222 int./230 exh. @ 0.050" lift, 0.509" int./0.528" exh. lift on a 112 LSA. 750 cfm Holley on an RPM Air Gap rip-off.
Why they used 36 degrees total timing I can't say. Nor did they say they adjusted the timing for best power. Usually Vortec heads do not want that much timing.
"Average HP per dollar" was $2.24 for the iron Vortecs, $3.63 for the Etecs, ca. 2009.
|02-04-2013 03:45 PM|
Like aluminum heads, it wants more compression to make up for the faster heat transfer into the coolant than cast iron, but this rewards you with more power. It likes the squish/quench tight .040 or a tad less but it's not crazy with very thin shim style gaskets which tend to abraid the aluminum. It likes a thicker composition or MLS gasket which then to get thesquish/quench dialed in pretty much drives a zero or near zero deck block. You'll find yourself experimenting with push rod lenghts compared to the simplicty of the L31 head.
They'll take about 30 pounds off the front wheels compared to the L31's.
|02-03-2013 11:51 PM|
|vinniekq2||on paper they look like good heads,decent flow.Are you considering the swap? I would like to know how they work for you? Would be great heads for a small engine|
|02-03-2013 10:57 PM|
has any one used the Edelbrook 60979 E-tec 170 aluminum heads in a votec head swap?