Aluminum headed 318s?

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Shainesboostin

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Was hoping to find some info out on guys running aluminum heads on a 318. I am doing a Magnum swap now, but my dad really liked the idea of building a 318. We had bought some parts for it, big cam, intake mani, ect. but when I pulled the intake, it had the small port heads. i was told when I bought the car it had the big port heads. So, decided to ditch it. Now, I was thinking someday would be cool to get a good set of heads on it. What combos do you guys run? Saw procomp heads, and other random companys.
 
Up to a certain power level, the small ports are best on a 318.
 
Pretty simple build, we have built many similar engines but used magnum block for roller cam advantages. Search "explain quench" to read a good thread about what it is and why it works. Its nothing crazy or exotic, just common sense. I have always liked that build article because it used a much better cam design than most, proving with magnum heads excellent exhaust flow(for factory head) that you dont need more exhaust lift or duration with that head. Also a good example of why you dont want high volume oil pump! Just changing viscosity got them some extra ponies.
 
How much power are you looking to create?
 
I assume your looking at edelbrock heads.
Non ported ones will produce 450 ish hp.

The main thing you got to remember when building a 318 over a 360 is that it's gonna need more gear and stall and the powerband is also gonna be moved up about 600 rpms or so.

So a 450 hp 318 will make peak power around 6500 rpm and peak torque around 5000 rpms. And be pretty weak under 2500 rpm where most cars doing 90% of there driving so gears are very important to make a 318 work I wouldn't go under 3.91.
 
If you are street driving, in my view the #1 thing to do is put in some pistons that will bring the CR up. That is the biggest drawback of the 318: the low stock compression height. If you do that, then the low RPM woes with lack of grunt go away; you just have a small bore 340. PS: I just read the article linked... that is exactly where they went with the pistons: KB167's. Use them and the .028" thick 1121G gaskets on an LA block (or Felpro 1008's on a Magnum 318 block) and you have instant good quench gap around .040"+/- with no extra machining beyond clean up, and you have a nice a 9.6 or so SCR for pump gas using some closed chamber AL heads around 63 cc's or Indy LA-X at 62 cc's , and pick the cam you want to tune the torque/HP curve. You just pushed the 'Easy Button' to the 350-400 HP neighborhood with good low end torque (if you don't go overboard on the cam). No need for high rear gears and higher stall TC's....
 
^^^^ yep, a small bore 340.... :) And that compression thing, that's what I wanted to do so bad to my low dollar 318, but I couldn't do it and keep the whole project under 500.00. The head gaskets I got in the kit were the .052 thick ones :( ..... I wanted the 1008 fel pro's .039 and then cut the heads .030 ..... it would have made a big difference to my motor.
 
I have a Duster with a 318 with Eddy heads, solid cam, pump gas, runs 12.40s, like it was said, build it like a 340 and it will run.
 
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