Mopar 340/360 Heads Help!

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scottylack

scottylack

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I am getting my 360 rebuilt, and I'm the gopher! I was told to get a set on NON SMOG heads for the motor ... I found a set of 3671587 heads... are these good for a build up? Are they non-smog? I think they were built for several years, first on the 73 340 and up till 76 on 360's ...
thanks!
 
scottylack said:
I am getting my 360 rebuilt, and I'm the gopher! I was told to get a set on NON SMOG heads for the motor ... I found a set of 3671587 heads... are these good for a build up? Are they non-smog? I think they were built for several years, first on the 73 340 and up till 76 on 360's ...
thanks!
Click to expand...

They were late 70's 360 heads with 1.88 intake valves. No better or worse than any other heads including the 915 heads with the 2.02 intake valves. The 1.88 intake valve size will perform as well or better than the 2.02 valve heads until the upper RPM range (6000+) is used. It has been erroneously coupled to the lower power output of the later 340's when in fact it lower compression among other changes that lowered the power of the later 340's not the heads.
 
The only difference between smog heads and non-smog heads is the smog heads have an air injection port below the exahust port where the air pump would inject air, the chmaber and ports are other wise the same. These ports are easily plug so there is no real reason to avoid the latter "smog" heads.
 
In Larry Sheppard's "How to Hot Rod a Small Block Mopar" he says the swirl port combustion chamber on the 360 Cast 308 heads are the best stock heads for a small block Mopar. He says to install some stainless steel 2.02 intake valves and 1.66 exhaust valves. They were produced for 360's from 1989-1991. Take a 5/16 tap and tap the smog holes. Get some 5/16 allen head setscrews and apply blue loctite to them and install them. I also posted this in a thread about 302 heads.
:read2:
 
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