Thread: 360 Heads on a 318

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I have a '72 Dodge Charger with a 318. I recently purchased some old 360 heads for $50 bucks that are in great condition to put on the 318. However I have been told that the 360 heads would decrease low end torque dispite the fact that they would give the car more power. Is that true? And whether or not it is true is it a good idea? And yes they have the hardened seats. The guy I bought them from said they didn't need any work or anything, he said just take the 318 heads off and bolt these on.

If you put the 360 heads on in factory form, you will lose compression. you may gain high end HP due to flow, but you will lose torque. However, if you shave the heads, you will have the larger valves and the higher compression. Many times, its worth the cash.

Ive got a 318 and the 360 head swap sounds interesting. Just wondering how much would you have to mill the heads to retain stock compression?

Why would I lose compression? 360 Heads have bigger valves which mean they let in more gas/air, which means a bigger explosion right? And what would shaving the heads do?

Also, how much good would it do me to get the heads ported and polished?

wow... ouch.. OK Ill bite... the 360 head has a much larger cumbustion chamber. Larger cumbustion chamber = less compression. your stock 318 probably had 8.5:1, after putting on 360 heads youll probably have closer to 7.5:1.
Casting #302 heads from the mid=late 80s Chrysler cop cars & taxi cabs with 318s have the small chambers but also have same valve size as 260

Drg84 said that if I shaved the heads it would make them equal to the engine and would thus not lower compression. What exactly is shaving the heads? I would figure that means sanding or grinding the metal on the face of the heads down, but wouldn't that make them NOT equal to the intake manifold? And how would I resolve that problem? I am in need of lots of information and recommendation with this because I while the car is not running right now, I am about to throw all of my bits and pieces together and get this thing running soon.

OK, keep in mind im not very knowladgable on Mopars, but the 360 would have a larger combustion chamber. Shaving the heads means removing the material from the bottom of the head uniformly acros in order to decrease the combustion chamber size. Usually, this is small enough to allow re-use of the factory intake. However, it may be needed to use a 360 intake to match up with the ports on the head. If not, than there should be no problems.

So, shaving the heads is pretty much like decking the block only your doing it to the heads? And that will increase compression? Why? You couldn't shave off enough make up for the difference in size if there is that big of a drop in compression could you?

So what does everyone recommend? I wanna put the 360 heads on for the extra power but considering it is only a 318 I know torque is already gonna be low. Is there something I can do to seriously increase torque? I was told that when replacing the camshaft you can specify whether you are leaning towards off the line torque or high end power. If I bought a new cam for low end would that help me with the torque and reap the rewards of bigger valves?

You may be able to get a orque gain due to higher flow, but thats not going to be that great. You will be able to shave up to .050 off your heads safely and gain the compression back on your heads. Due to the size factor(318) dont look for Gobs of torque. your not going to find it. Lean towards HP, and youll get it. If you want a lot of Low end, get more cubes.