Mopar [HEAD] Aches PLZ HELP!?

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<69DizartGT>

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Hey folks, kinda new to building engines, as this will be my first engine build, here are the specs, got a 74 318 block bored .030 over, keith black silv-o-lite flat tops, Comp cam 260H cam, holley 600CFM vacuum secondary carb, dual plane manifold, and 74 360 smog heads, nice valve springs for the cam, nice lifters and rods, but my question is, what kind of heads SHOULD I have? From what Ive read, the mid 70's 360 heads on a 318 SUCK, I dont realy know, so Im asking what the best STOCK mopar heads are for my set up? More horsepower = more better :) . I hear tell story of X Z J U O heads etc. and then numbers like 915 etc., tell me what heads I should be scaviging for,only looking to spend about $200-$300 MAX! Only gittin paid $200 a week, and 16 year old insurance.. well.. sucks. There are a few local auto yards, tell me what I need! I am willing to get some shaving done, and port n polishing is no biggie. Ill post my head casting #'s and you all mite be able to tell me if it should stay or go, from what you know now, what do I need?
 
For a 318 I wouldn't use anything but a 302 casting from the mid to late 80's, as they are a small closed chamber style head and from what we've found that they are the best heads for the 318. The 360 or magnum head, port volume is too large for the stock 318 type engine for street use and will not have the tq. or power in the lower rpm ranges. If your not turning this engine over 5000/5500 rpms this is the only way to go IMO.
 
Are these the heads that are on your car at the moment?
3671587 1973-1976 340 360 1.88" 1.60" 65cc-73cc

You can pull valve cover and find casting number. If so, considering the budjet you mentioned, you have a couple of choices. First you need to find if size of intake runners matches 318 heads, or the larger 360 heads. Are pistons in engine now zero decked, or down in the hole?
In my opinion, your choices are to mill the heads you have now and port match them with your intake, or to get 302 heads, which have a smaller chamber size, increasing compression, and port matching them to your intake.
I recently bought a set of 340/360 J heads, and a set of 302 heads for my 318, and after doing considerable research on which would be the best for my street car, as BJR stated above, decided the 302s would be best for my application. I'm port matching the intake to heads, and doing some other minor home porting, adding thin MP head gaskets, and installing. I purchased the freshened 302 heads for right around $200. Just for a heads-up, there was an ad on this forum yesterday, of a person wanting to sell a set of 302 heads pretty cheap. Do a search of 302 heads, and you should find it right away. Hope this helps, Mike
 
but my question is, what kind of heads SHOULD I have?
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Well, the limited budget says a set of 360 heads will fit the pocket. The larger head window will give the car a lazy bottom end. It'll pick up once your at speed.

Porting a set of 302's is a catch 22. If you can do it, then being without money is something your not.

A good cheaper compromise is a Magnum head. The added rocker ratio will add intensicty to the cam with more lift. The smaller head chamber will keep compresion up. Use with a .040 (Or close as possible) head gasket and a dual plane intake.

Resell what doesn't fit the Magnum head set up and get what you need. Exchange brand new parts for the correct ones needed.

(Lifters, springs and anything else.)
 
rumblefish360 said:
Well, the limited budget says a set of 360 heads will fit the pocket. The larger head window will give the car a lazy bottom end. It'll pick up once your at speed.

Porting a set of 302's is a catch 22. If you can do it, then being without money is something your not.

A good cheaper compromise is a Magnum head. The added rocker ratio will add intensicty to the cam with more lift. The smaller head chamber will keep compresion up. Use with a .040 (Or close as possible) head gasket and a dual plane intake.

Resell what doesn't fit the Magnum head set up and get what you need. Exchange brand new parts for the correct ones needed.

(Lifters, springs and anything else.)
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I know the kid doesn't have the money, but what kind of afterrmarket head is the best for the 318? Does AFR produce something for Dodge?
 
AAWJ L 3769974 1684 is what I pulled from the engine. 1.88 1.60 valves.

THanx for the replys, it does help considering I barely know what Im talkin about. Now, it sounds like its the 318 302 heads I need, the pistons arent top level, and that will definately be milled so there are at the deck. Would the 340 X heads be worth it? If I milled them down a bit maybe, or leave em stock? Regardless of budget, would they be nicer than the 302 heads? If so, how much does a nice pair cost? OR how much does it cost to have head valve holes bored to put the 2.02/1.60 valves in a 302 head? Almost done buggin you all :) thanx for the help thus far!
 
LJS30;
but what kind of afterrmarket head is the best for the 318? Does AFR produce something for Dodge?
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Street and street strip and ported some for the strip, Edelbrocks heads are probably IMO the best. The Mopar head should be better but at a cost of a few bucks more. The problem with the two mentioned heads is the 2.02 valves being a bit large for the smaller engine displacement and port cc volume...smae problem for effective use.

Does this mean it is a losing proposition? No. Just you can do better with a better sized port and valves that, are not currently avai. on the market in aluminum.

I am not aware of a head from AFR for a MoPar. Just extensivly for the Chevy and a bunch for the Ford.
 
So are bigger valves better, if the chambers r still smaller? Would putting 2.02/1.60 valves in a 302 318 head be a good Idea? Keep in mind the pistons are .030 which should raise the compression a bit with 318 heads. The pistons are 10.5:1, are bigger valves better?
 
69DizartGT;

AAWJ L 3769974 1684 is what I pulled from the engine. 1.88 1.60 valves.
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1975 - 360 heads

the pistons arent top level, and that will definately be milled so there are at the deck.
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Milling the block is not what I would recomend in getting the stock pistons to be at zero deck but would rather point out Keith Black has a set of pistons to be at or near zero deck. From there I would mill the block to achieve a zero deck piston. If these are the pistons you have, then go ahead with the plan.

Would the 340 X heads be worth it? If I milled them down a bit maybe, or leave em stock?
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IMO, Hell no! If you have a set, sell'em and roll the money over into something else on the car/engine. Leave'em stock for best money on resale.

Regardless of budget, would they be nicer than the 302 heads?
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Only if your racing for big dollors and have to use iron heads.

If so, how much does a nice pair cost?
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To much. Not a good bang for the buck.

OR how much does it cost to have head valve holes bored to put the 2.02/1.60 valves in a 302 head?
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IMO, that would be a bad move. You could use the smaller valve to keep torque up and live without the few HP up top. You'll probably ET better with the smaller valve and be 1 or 2 mph behind the larger valve at worst.

Almost done buggin you all thanx for the help thus far!
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Oh bummer. I was enjoying our little chats. Bug away anytime. No problem so long as your picking up on what were all saying.
 
I think Im understanding a bit more, and I asked the fellow about the 302 heads, they are 1990 302 heads, does it matter that there not late 80's? Though they would've been made in 89, are all 302 heads the same stock? If so, they will be my new heads.
 
<69DizartGT> said:
So are bigger valves better,
Build dependent, in a 318, more likely not in your case. The dyno may say one thing, the feel of the ride is another.
if the chambers r still smaller?
Chamber size being smaller (If such is the case) will keep the comp. ratio up and not give away any power. You'll need approx. 1 full point or better to equal a iron head.
Would putting 2.02/1.60 valves in a 302 318 head be a good Idea?
No
Keep in mind the pistons are .030 which should raise the compression a bit with 318 heads.
going .030 even with a stock replacement piston will raise the ratio. Actual part number to the piston would help. Otherwise, I'm left to fly blind and assume. I have assume.
 The pistons are 10.5:1,
well, that helped, but only a little. The pistons can be rated @ 10.5-1. But the actual ratio is dependent on the rest of the areas. Like head cc amount, gasket thickness, gasket bore, where the piston actually sits, domed piston, how many cc's, valve relief cc's. piston above deck amount. It is just not that simple to say I have 10.5-1 pistons. are bigger valves better?
tsk tsk, repeating questions get answer exactly the same way as the first one did. Or, (he he he) See above. ;)
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The Mopar engines book has ways to calculate actual ratio. Piston calcs on line are only as good as the info entered.
 
rumblefish360 said:
69DizartGT;

Oh bummer. I was enjoying our little chats. Bug away anytime. No problem so long as your picking up on what were all saying.
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Your a good guy, Rumblefish360
 
<69DizartGT> said:
I think Im understanding a bit more, and I asked the fellow about the 302 heads, they are 1990 302 heads, does it matter that there not late 80's? Though they would've been made in 89, are all 302 heads the same stock? If so, they will be my new heads.
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The 302 head was instaled on engines from 85 - 87 I believe. I'm not to sure when they stopped installing them or making them.
I know after 1991, the 318 "LA" was stopped in favor of the Magnum set up. What was on top of 318's from 87 to 91 i'm not sure of. But they were more likely to be a swirl port head good for the same treatment as a 302 if not being a 302 head itself.
 
Blues65 said:
Your a good guy, Rumblefish360
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Thank you, now shhhh, don't let the secret out. They be coming over my house looking for chalk board lessons again. He he he he.
 
Okay, ill stop buggin ya now, and for this being my first thread on the website, the help I got was greatly appreciated! Thanx everyone, and thanx for dealin with my newness to this engine building stuff rumblefish!
 
somebody can correct me if im wrong but as long as the 1990 318 head has shaft mounted rockers it will work no problem. double check the casting number too again because the 360 had a swirl head its casting # is 308.
hopefully i didnt confuse u , alan
 
<69DizartGT> said:
Thanx everyone, and thanx for dealin with my newness to this engine building stuff rumblefish!
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Were all new to something at some time. My first engine build was at 20.

Also, the 308 is a open chambered 360 head.
 
302 heads were standard from 1985 through 1991. They are getting harder to find. From what I have seen in the pick-n-pull yards, your best bet is to look for an 85 - 91 Ram pickup or van. Be careful though... some of the early 85's did not have 302 heads! Best bet is to pull the valve covers and check the casting numbers before starting to pull the top of the engine apart... it will save a lot of wasted time!

I saw one guy in the yard pulling some heads for his project, when all of the sudden there was an outbreak of cussing... he pulled a set of open chambered heads from an 85 and had not bothered to check the casting numbers first! I was laughing to myself inside, but didn't dare let out my amusement... I didn't want to have any wrenches or fists thrown in my direction!
 
To be safe I would say that the 302 head was from late 1985 - early 1991.

I usually keep my search limited to 1986 - 1990 vehicles. That way you will know that it will have the 302's... unless someone swapped out the heads in a prior lifetime!

Keep your eyes open in the salvage yards... I found a nice set of Edelbrock heads in there once... for $45 a piece, it was a memorable day! You never know what you might find.
 
TheDemonator said:
I saw one guy in the yard pulling some heads for his project, when all of the sudden there was an outbreak of cussing... he pulled a set of open chambered heads from an 85 and had not bothered to check the casting numbers first! I was laughing to myself inside, but didn't dare let out my amusement... I didn't want to have any wrenches or fists thrown in my direction!
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Shame on him, also could have been 308 heads.
 
Are the 302 heads, stock as they are, gonna be better heads than the 73 360 heads? The 360 heads have minor port work, but will have much less compression. I can do the port work with my dad on the other 302 heads
 
I think the cheapest way to go would be pull the 360 heads and mill them down to get your compression up. The 302s would be good but they are still almost 30 years old and will need work. Magnum heads would be great but are hard to find that arent cracked.
 
Well thats jsut it, I dont know how much it will cost to mill em down, but at the same time, dont know how much it'll cost to get/find high lift valve springs for the 302 head.

73 heads milled down price? horsepower increase/decrease on stock 318?

302 heads shipped, ported, valve springs, seal price?? horsepower increas/decreas on stock 318??

I dont know what to do, I think Im gonna keep the 73 heads
 
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