? on Head machining

[Drg racr]

I'm on the lookout for a set of perf. heads. What I have is a set of 4101051's already rebuilt with about 40K miles on them and very clean. What ball park figure would it be to massage these heads to work on a 400 horse motor?

 

[skrews]

Need more info about the rest of the engine. A set of untouched 360 heads are capable of supporting 400 HP if everything else is there.

 

[Drg racr]

Stock rebuilt 1972 block, .030 over, flat tops, crank turned .010 on mains and rods, ARP bolts. I'm going to run a .497 lift cam, roller rockers, Air Gap intake, 750 Holley, Super Comp headers, 904 trans, 3800 stall conv (the car is set up for a 4-speed right now). Already have 4.56 SG 8-3/4 under the car.
Car is all steel, stripped interior, 8-pt cage, battery relocated.
Car will not be on the street. I'd like to be in the 11's, but I may have to lighten the car considerably.

 

[moparlover]

if it's race only, and you want to run race gas you could get 12.5:1 pistons or something, and instead of putting money into those heads get a set of aluminums.

reason i say that is 1. comp ratio alone will give you a ton more power, and 2. the machining / new valve / porting money spent on iron heads would be fine for a "numbers matching show car" but yours is not for that. there is no good reason to go with iron heads except for factory original or if your racing bracket requires them. out of the box aluminum heads will have large valves, better flow, better cooling, etc.

if you cannot afford a lot of upgrades right now, your best bet would be larger valves on the heads if they dont already have 2.02's, and a bigger cam (higher rpm range) with solid lifters so you can run 7000-7500 rpms. the valve springs will have to be spec'ed for the cam and clearances checked. a machine shop can check that stuff for you and tell you if the heads need to be milled or if they check out ok.