Swirl Port heads

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65Vart

65Vart

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In my search for some 318 swirl port heads I have come across two castings. A 302 casting as well as a 714 casting. What's the difference? I am hearing mixed messages. So I ask the people that know . These will be going on a 71 LA motor.:profilel:
 
You want the 302's. They should have a heart shaped combustion chamber. These were the best of the non-Magnum 318 heads. They're fine in stock form and respond well to larger valves and basic porting work.
 
Understood, 714s are also heart shaped chambers with the smaller valves same as 302s. (1990). I have heard it the same head with a different casting number................anyone know about this?
 
probably identical, its the chamber shape that counts. Same-o same-o..like an X and a 2.02 J,U or O head...dont just pay for the "X" when all else is identical.
 
I also heard the 714 was "ported deeper" what ever that means for a 318. Any engine builders know?
 
302's and 714's are identical. I have both sets, cant find any difference between the two other than the 714's have heavier nail head exhaust valves, rotators on the exhaust valves, and the heads are factory machined for positive valve stem seals. They also "seem" to be heavier than the 302's, like it just has more meat in the casting, but that hasnt been confirmed. Have both tested for cracks, and run the best ones. Six in one hand, half dozen in the other.

Oh, and NEVER trust the factory "rated" cc's of any head. Most are almost always several cc's larger than they are spec'd out to be. Most 302's are usually between 62-64 cc's uncut.
 
TheCraigMachine said:
the 714's have heavier nail head exhaust valves, rotators on the exhaust valves, and the heads are factory machined for positive valve stem seals.
Click to expand...

I'm convinced that they are just a change over in numbers, possibly signifying what plant they were made in. Sometimes manufacturers will do that so they can help identify recalls, if and when they take place.

My 302 heads have the flat/ nail head valves with rotator retainers and short springs on the exhaust with positives on the guide seals.
 
DaveBonds said:
My 302 heads have the flat/ nail head valves with rotator retainers and short springs on the exhaust with positives on the guide seals.
Click to expand...

Hmm. That's interesting! I guess my observation of the differences between the two are moot! This does make sense since my 302's were off a car, and my 714's were off a truck.

So all else being equal, 302's and 714's are the exact same head! :cheers:
 
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