427/505 sohc build questions

[hbstang]

i have a set of original ford aluminum sohc heads and would like to build a 500 inch or so sohc with it.heads are in nice shape with no weld repairs,so would those in the know build a 700 hp street strip engine with them or buy new ones.just curious to what builders think.

so other questions are aluminum vs iron blocks.does the aluminum block grow enough in the heat cycle to affect the main cam chains,tension wise?
would the iron block be more stable,bbm/pond.?

cams i have are new 282 @.050 duration from lsm cams,and .470 lobe lift,factory dual quad intake,and not much else.carbs to start with and maybe efi done the road.

[428kidd]

Im not a SOHC guy but the heads will support 700 hp use them. Block wise im a cast iron guy , better ring seal ect.

[jayb]

Factory Ford aluminum SOHC heads are pretty scarce, I personally wouldn't use them on anything but a stock restoration of an SOHC engine.  They will certainly work with a 700 HP engine though.  On the blocks, aluminum expands at about twice the rate as cast iron with temperature, but they both expand and will put stress on the chain when the engine is hot.  In either case I'd recommend tightening the chain bolt to 60 inch pounds on assembly, then re-tighten after the engine is up to temperature to 110-120 inch pounds.  This process takes the growth of either a cast iron or aluminum block into consideration.  Make sure when tightening the chain that the rockers are slid over, so that pressure from the valve springs does not induce a force on the chain and skew your torque measurements.