318 swirl port heads

[mopardog54]

Has anyone have any info 318 swirl port heads Casting #4027163

[dwc43]

What do you need to know? A good set of X or J heads out flows them and with 2.02 valves in them would make them a better choice for performance over the swirl ports. There's nothing really speacial about them other than a cc that makes the mixture swirl. No hp gains at all. This was done to improve combustion to get past the epa restraints put on the manufacture so it would pass E tests.

[mopardog54]

I appreciate the info. The 340 heads are hard to come by, if you can find the them there pretty steep.

[dwc43]

Welcome, anytime.

[rumblefish360]

http://www.moparchat.com/forums/show...threadid=82493

[dwc43]

The #302 swirl port castings are the best choice for a mild 318 buildup if you are having them ported. If you are going the un-ported route, go with the 360 heads but have them milled.


See, not worth using. The port job will cost too much and wont gain as much as the 360 head will give you. Best to use het X or J head.

[Bill55AZ]

Magnum heads have the bigger ports and valves of a 360 head, smaller combustion chamber of the 318 head, and your exhaust system will bolt right up to them. They flow real nice as is, no porting required, no milling needed. Crate engines use them and I hear they are good for up to 400HP in stock form, assuming the heads are the limiting factor in your combination of goodies. You will need AMC lifters and special length hollow push rods. I got my lifters at AutoZone cheap, pushrods from Mopar Performance, not the least bit expensive.
Only issue is angle of intake manifold bolts, but there are now 2 companies making carburetor type intakes for Magnum heads.

Just a suggestion....

[dwc43]

The intakes are not available yet and you have to look at the extra cost of installing these heads too. X J or W heads will make much more power and the W's are a little cheaper than the magnum R/T heads, so this is not really worth messing with considering better heads with less cost are out there now.

[Diego SST]

bare magnum heads are $135 each brand new and flow as well as 340X heads straight out of the box.

[Bill55AZ]

http://www.northernautoparts.com/Pro...ctModelId=7839

$182 at Northern Auto Parts, this manifold fits LA and Magnum heads.

[rumblefish360]

How are these power + people. It's a copy of Edelbrock intakes. Are they from across the pacific ocean?

[Bill55AZ]

Don't know, but they claim to have better casting methods, here is another link with pictures and their link to pictures of Chrysler versions of their product line...
http://www.professional-products.com/Power_Plus.html

[cuda65]

This thread got me doing some research. I have I believe the 8th edition of Mopar Speed secrets/Engine guide put out by mopar performance around 10 years ago. There is a section about the 318 high po. swirl port heads and how it adds 55 h.p. over the 360 heads. If you need page numbers, ask and I'll get them to you.

[mopardog54]

Cuda65,
What book have you got and where can I get a copy? I'd like
to find as much as I can Mopar Small Blocks as I can. Thanks

[dwc43]

You can get the mopar engine books from the mopar dealer, but you'll never get 55hp with swirl ports over 360 heads. They dont flow as much as a 360 head will. It's just a stock 318 head with a moded combustion chamber. It does not raise compression or do anything other than to get the mixture to swirl a littler before combustion so that it is more complete burn so it would pass epa tests.

[cuda65]

Originally posted by mopardog54
Cuda65,
What book have you got and where can I get a copy? I'd like
to find as much as I can Mopar Small Blocks as I can. Thanks

The book is Mopar Engines- Speed secrets and racing modifications for chrysler v-8 and 6 cylinder engines. 8th edition.

the book is about 10 years old, original cost is 20. part no. p5249010.

I have the swirl port heads on my 65 cuda, and I think they are a solid head. There is information on p.73 of the engine book that addresses the head issue providing a line graph displaying the difference between a stock 360 head, ported 360 head, and ported 318. The difference between the stock 360 head and 318 ported head is about 50 h.p.

If you need any other help, let me know.

[72Challenger]

Gee. A ported head made more power than an unported one. What a surprise.

How about you tell us what the ported 360 head did compared to the ported 318? My Mopar "A" engine book form 1998 doesn't have the section you're refering to. However, it does say, refering to the 302, and I'll quote:

"The intake port on this head is smaller and is harder to make flow with high lifts."

He does have great things to say about the swirl port 308 heads for the 360 however. Not because of the swirl port design, but because the exhuast port is modeled after the W2 head and outflows the "X" head by a good margin.

I know this to be a fact. I've just finished porting a set of "X" heads for use on my 340. I got over 270 CFM on the intakes, which is better than untouched W2s. However, the exhaust sides are very bad by comparison. I did this because I already had the heads and this is a budget build. But if I had a few more $ to put into it, I would have just gone with aftermarket heads and been done with it.

[72Challenger]

By the way, did anyone even bother to research the casting number mopardog54 gave us? I show the 4027163 casting as being used from 1977-1982. This would NOT be a swirl port head anyway!!!

[rumblefish360]

DWC, love ya to death but "but you'll never get 55hp with swirl ports over 360 heads."
?MoPars a lieing to us?
A put some good value on port velocity over brute volume in the right combo. (Key words, "Right combo"
Now if were racing the crap out of the car....Crystal ball says 360 heads.
All though there getting a little harder to find these days. Burns me when some clown thinks he has gold.

[dwc43]

Rumble, you mis read. I agree with you. You'll never get 55hp woth a 318 head over a 360, never no matter what that guys book says. THe swirl port was designed for that head to get better emission so it could pass eap test with a cleaner burn. It was never intened to increase hp and it does not even by Mopars own numbers.

[turbododge]

What the Mopar book was pointing out with 55hp difference, is that heads that flow about the same (ported 302 and stock 360) can have significant performance differences. If you see a complete torque curve on the comparison, you would see a much wider torque curve on the the 302 heads because of the better velocity and swirl at low rpms. They never claimed that a ported 302 would outdo a ported 360 head in MAXIMUM, all out, horsepower, but only that the ported 302 would probably be a very good choice for up to a 350 horsepower application, because of the broader torque curve and crisper response.

[Plymouth10]

Only real benifit of a 302 type casting head is the closed chamber/fast burn , true a fully ported 302 can flow about the same as a 360 J "stock" but a fully ported 308 or x,j,u,o, can come very close to a W-2 {standard econo} head,thats why i dont see putting a lot of money in a set of 302s, 308s yes...best sb iron la head made. Stage 3 port on 308s with 11/32" stems is a great set of heads. but then a ported set of W-2 are a better choice than the 308s i guess it is all about the flow potenial of the heads. {for me anyway} i have used 302 casting heads, and 273c closed chamber heads on 1/5 tracks, with lil work and did quite well, for that application.