edelbrock heads on a 318

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NEWATTHIS

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Hi,first Time Here Glad To Be Here Because I Need Your Help And Advice. I Have A 1974 Dodge Dart Sport With A Rebuilt 318. When I Got This Engine Rebuilt I Made One Mistake, I Never Changed The Pistons. Iam Running The 2176 Eddy Manifold. With A Eddy 600 Carb.a Comp Camp Xe268 High Energy With 477/480 . I Am Running A Set Of Headers With Dyomax Mufflers. To Raise The Compression I Was Thinking About A Set Of Eddy Heads 60779, I Plan To Run A 3000 Stall With 410 Gears Any Help And Advice Will Be Grateful Thank You
 
A completely wrong way to go.
You would seriously be alot better off milling the stock head down for a ratio jump and working the OE head with a larger exhaust valve.
 
What Rumble said. You lose the bling factor, but the RPMs are too much head for that. You will get more performance by working the heads you have already. Have a good shop do them up, and you'll get more of the performance you need for less money.
 
Thanks For The Information, You Saved Me Lots Of $$$$.thanks Again. Newatthis
 
I'll play devil's advocate on this one...

Have you thought about the Edelbrock heads for Magnums? They have a 58cc chamber. That and a skinny head gasket would actually get you decent compression, even with the crappy stock pistons.

Its a more involved swap, because you'd have to buy AMC lifters, different pushrods and rocker arms in addition to the heads. Unless you paid Hughes or someone to drill the Maggie heads for your old intake, you'd have to buy a different one, but that Edelbrock Performer RPM Air gap is well, badass.

Keep in mind it takes 50 lbs off the front of the car, and you get a way better flowing head that would be worth something when you were done with it. Probably not a whole lot more expensive than having a ton of labor done to your stock junk anyways, especially after you buy valves and springs.

As far as the head being too big, they flow about what the TFS Twisted Wedge/AFR 185 head does on a small block Ford, and lots of guys make lots of power with those heads on a 302.

I've got a 318 in my Dart, and I've actually thought about putting off the 5.9 swap for a year and trying this same thing, just to see what it could do.
 
Those closed chambers are just begging for flat-top zero-deck pistons, which is what I'd recommend anyway. You have to remember that you'd lose combustion efficiency with the change in head material to aluminum, which may or may not be made up for by the increase in compression due to the smaller chambers.
 
You have to remember that you'd lose combustion efficiency with the change in head material to aluminum

FYI for new guys, that would be heat he is refuring to, not flame front travel or complete burning of the air/fuel mixture.

which may or may not be made up for by the increase in compression due to the smaller chambers.

Another FYI for new guys at this. Beware of the cylinder head cc's in the stock head to the new head. When making the move from iron to aluminum, the heat goes out of the chamber faster through aluminum. This is where you find the mention(s) of moving the compresion ratio up 1 pt. to recapture what is lost in the quicker heat transfer.

Those closed chambers are just begging for flat-top zero-deck pistons, which is what I'd recommend anyway.

HELL YA! and ME 2! Best route to go with a closed chambered head.
 
Wow, Thanks For The New Information, About The Eddy Heads, Its Good To Her The Pros And Cons Of There Heads Some People Like Them And Some People Dont. I E Mailed Edelbrock And Told Them About My Engine The Stock Pistons And All The Performance Add Ons I Have On It. They Told Me That There Combustion Chambers Are 63cc And Running 2.02 Valves Is Not A Problem. I Also Know That He Works For Edelbrock And He May Just Want To Sell Me A Product. He Never Told Me The Details That You Guys Have Told Me, Yes These Heads Are Alot Of Money, I Dont Know If There Worth It, Never Thought Of Magnam Heads Never Thought About Heat Loss. Thanks For The Detailed Information Guys I Am Learning , And Thats Why I Joined Up On This Site. Thanks Again Newatthis
 
Whoops, should've explained that more thoroughly...

It may be a cheaper option to go with a set of ported closed-chamber #302 heads from a late-80's truck/van 318. Although they wouldn't flow as much as the Eddies, they would still be a big improvement from your stock open-chamber heads. In fact, I have a pair in my garage just waiting for a cleanup (no porting, too much work for me now and not really worth it unless I go all-out) to go on my '70 318 along with a Performer intake, Lunati 262/268 cam, and iron 360 manifolds. Still not as much compression as I'd like (hoping for at least 9:1), but the high-velocity swirl-type ports and fast-ramp cam should help that out too.
 
Thanks For The Information Mopekid-3, I Want To Ask You And Everyone Else Out There Is Question. Money Is Always A Issue In Everything We Do In Life. But Lets All Put The Money Aside For A Moment And Lets Talk About Heads And Heads Only. Money Aside, Are The Eddy Heads A Better Head The My Reworked Stock 318 Heads, Are They Better Then The 302 Heads, The Reworked 360 Heads And The X Or The J Heads. Please Remember When Answering This Question Leave The Money Part Out Of It. Thanks For The Feedback Guys The Information I Get Is Help Ful In Making Up My Mind On What To Do. Thanks Newatthis
 
All in all, yes. They have the potential for the most power, but it's an issue of whether or not your little 318 could use all that flow to its full effect. Remember, the RPM head was designed to go on 340's and 360's. In ported form some even use them on 408 stroker small-blocks. Money aside, the RPM's might be too much for your engine. Intake charge velocity is more important than max flow when dealing with street engines, and the RPM ports/valves are probably too big to keep good velocity at lower rev's, which a 318 needs in order to have decent torque. I'll attempt to lay out all the choices in order of "potential":

Stock 318 heads, pre-1986: Open chambers, small ports, work fine when reworked but don't have the nice closed chambers of later heads

Stock 318 "#302" heads, 1986-1991: Closed chambers, slightly smaller "swirl" ports, probably best option for milder street performance and racing in some cases when well-ported

Stock 360 "J" heads, 1970's to 1980's: Bigger open chambers, larger ports, good option for higher-performance street 318 builds as long as higher-compression pistons are used and smaller 360 intake valves are retained; can be upgraded with larger valves to basically become "X" heads

Stock 340 "X" heads, 1968-1970: Arguably the best LA performance heads, open chambers, big ports, big valves, a bit much for a street-oriented 318

Magnum heads, 1992-2002: Arguably most versatile and efficient small-block heads with best stock low-lift flow (great for a street engine), closed chambers, great potential on a 318 but require some valvetrain mods to adapt to LA (pre-1992 318, 1993 360) block and are a bit tough to find in solid condition

Edelbrock RPM heads: Aluminum aftermarket performance heads designed for the 340 and 360, closed chamber, big ports, big valves, great design but ports too big for a street 318

Indy Cylinder Head 360 heads: Aluminum aftermarket performance heads designed for max-effort barely-streetable stroked engines (at least 408 cubes), you would never need these unless you were doing some serious racing and had to stay with a small-block

Personally I'd go with ported 302's if you can find them, or cleaned up 'J' heads if you can swap pistons.

IF you went with the Edelbrocks, you'd need higher-comp pistons and/or the will to rev your engine really really high to make power (which really annoys me personally, if you want that then go with a turbo 4-banger).
 
The Edelbrock heads are better than most any iron production heads (W2 would be an exception), but they would probably be overkill for your setup.

When you say you never changed the pistons, do you mean you are still running the original pistons/bores? If this is the case, and you wish to raise compression and/or make more power, that's where you should spend your money.

Now, if your current heads are shot and you have a stack of cash burning a hole in your pocket then by all means buy the small chamber Eddys. BUT don't expect a whole lot unless you change pistons as well (KB 167s would be a reasonable choice). And you'll certainly want a Performer RPM manifold to get the most out of the heads.
 
..........U r way better off with the 85-91 #302 head......they r a 25 hp bolt on over the x or j head.......318s dont need and cant use the big 340-360 intake ports, unless it is an all out hi comp race engine.......4 best driveability and bang 4 the buck #302s r the only way 2 go........kim.......
 
Food for thought, MoPar used to sell ported 318 heads, listed in there catolog as delivering 55 more HP than the 360 heads.

What your really after on a 318, in a big way, is port velocity. With high port velocity, you can not only get a great mixing of the air and fuel for a highly atomized charge for a much more complete and powerful burn, but a high port velocity can actually fill the cylinder up more than a larger port head.

There is a time and place for a 360 head. I'd reserve a 360 head for a serious street stomper or light drag car and it's asocc. gear. High rear gear and stall, light weight car, etc........
 
Before I Start I Would Like To Say A Big Thank You To Everyone On Your Feedback About The Eddy Heads. My Knowledge Is Is No Were As Deep As Yours, Thanks Because I Really Do Need Your Help. Iam Felling A Little Mixed Up About All Of This. The Advice That You Guys Give Me Is Different Than The Eddy Guy At Edelbrocke. My Engine Was Rebuilt Last Year It Is At Zero Deck With Flat Top Pistons. Mopekid Said That These Rpm Heads The Ports Are To Big And The 202 Valves Are To Big To Keep Good Velocity At Lower Rpms. Everyone Says That It Is To Much Of A Head And To Much Flow For The Little 318. If You Go To The Eddy Website I See That The Eddy Heads With The 202 Valves Are On The Ford 289 And The 302. The Chevy 302, And 327 Also Run The 202 Heads. Except For The 327 Which Is Only 9 Cubes More Then The 318, Why Does In Work Onm The Brand X Engines But Not The 318? Thanks To All You Guys For The Information, I Will Now E-mail Edelbrock Armed With Some Great Questions About There Heads. Eddy Says Tha T There Heads Part 60779 Works On The 318,340,and 360. I Will Ask Them All These Questions (1) Will I Lose Combustion Efficenty With The Change To Aluminum. (2) How Will The Heat Loss With Aluminum Effect Performance.(3)will The Compression Ratio Drop Useingthese Heads With The Stock Flat Tops.(4) You Say That These Heads Work Well For The 318,340 And The 360, But Are The Ports To Big For The 318.(5) Are These Heads To Much Flow. (6) Are The 202 Valves To Big To Keep Good Velocity At Lower Rpms, And Will Gears Like 410s Help Solve That Problem. (7) Will I Need To Ru N Higher Compression Pistons With These Heads. I Will Ask The Guys At Edelbrock All These Great Questions That I Got From You Guys, If There Is Anything That I Missed Please Let My Know, I Will Post There Responce On This Website. Thanks Again Guys, You Have Been A Big Help Later Newatthis
 
Why Does In Work On The Brand X Engines But Not The 318?
It does work and better than the brand F or C heads.

Let me ask you 1 question or so.

What is your plan?
How fast do you want to go?
Why did it take you this long to answer on piston height.

Generally speaking, when a question is asked here, if theres not enuff info giving to begin with, we, the responders to the question error on the side of caution and generally speaking offer advice on a more street orianted performance build up rather than a hot street or race type build.

If your not coming foward with details and what you want/expect out of this engine, then all the info your getting doesn't properly apply.

Enter the wrong numbers into the computer, you get a wrong answer.

We are no different. Come forth with some answers so you can get better advice and proper advice for the direction your going in.
This way, you'll achieve your goal the first time out instead of the second or 3rd time. Unless you don't mind spending lots-o-money.

(1) Will I Lose Combustion Efficenty With The Change To Aluminum.
Yes, aluminum has a higher heat transfer rate than iron.

(2) How Will The Heat Loss With Aluminum Effect Performance.
It will act similar to being down 1 point of compresion.

(3)will The Compression Ratio Drop Useingthese Heads With The Stock Flat Tops.
Best way to know is to know your engine. Starting with the exact amount of cc's the head has, gasket to be used vs. the stock one, how far down the hole the pistons are now, overbore if any, so really that's bore and also stroke.

There are on line ratio calc's that should be looked into.

(4) You Say That These Heads Work Well For The 318,340 And The 360, But Are The Ports To Big For The 318.
That actually depends on there intended useage. What are you planning?

(5) Are These Heads To Much Flow.
It's more of a port volume issue rather than how much they flow.

(6) Are The 202 Valves To Big To Keep Good Velocity At Lower Rpms, And Will Gears Like 410s Help Solve That Problem.

In short;

Yes & yes.

(7) Will I Need To Ru N Higher Compression Pistons With These Heads.
Again, this is build dependent. Givin the fact of your running a zero deck piston now, that will give a good quench area with a .039 gasket, your ratio should be very good for most applications from a basic grocery getter to a mild strip car.

The way I calc up the deal;

Standard bore 318. 63 cc head chamber and then add 5 cc's for valve reliefs, .039 thick/4.00 bore gasket will equal a 9.55-1 ratio. It'll be 9.71-1 @ a .030 overbore. 9.84-1 @ .060 overbore.
 
Oh good gravy, everytime I hit enter to skip a line, the dang computer would upload it as a reply. What a major pain! But it's done. Whew!!!!


Do you have a desk top dyno program by chance? It's a cheap but decent little program for approx. $40 from sumitt or jegs racing that can help you understand the effects and pro/cons of engine workings. I think this would be a good item for you to grab and play with.

Just do not get hung up on making lots of HP and ignore the torque. Even more so with the 318.
 
The Edelbrock heads work on 302's and 327's because those engines are designed to be high-po screamers that rev to 7000 RPM's. 318's are completely opposite of that; that's why they went in everything from 4-door Valiants to full-size pickup trucks. If you want your 318 to run like a 302 or 327 then by all means go ahead, it's just that we thought you might prefer a more street-friendly engine with more torque.
 
Hi Rumblefish360, Thanks Good Advice I Will Try And Be More Infocus When Asking Questions Again And With Better Detail. To Answer Your Questions Here They Are. When I First Got This Car I Just Wanted A Cruiser Get The Stock 318 Rebuilt, Change To A Four Barrel Carb And Intake. Get A Nice Thumping Cam For The Sound And Add Headers And That Would Be It. Then I Got Hit With The Power Bug I Wanted More And More Power. I Want The Gears(410) 3ooo Stall And Of Course Better Heads, If I Had A Chance To Do It All Over Again,i Would Have Bought A Crate 402 Motor, But Its To Late The 318 Is Already Rebuilt. So If Said Okay, I Will Get As Much Power Out Of This Engine That I Can. My Plan Is For A Nice Street Car, If I Cant Have A 402,360 Or A 340 Then Of Baby I Want This 318 To Push Out As Much Power As It Can . This Will Just Be A Street Car. I Mentioned The Eddy Heads Because I Wanted The Most Power I Can Get. About The Piston Height I Mentioned Before That The Engine Was Rebuildt With The Stock Pistons But I Didnt Know That They Were At Zero Deck. I Phoned The Guy Who Rebuildt This Engine Last Year, I Found Out From Him That He Put In Flat Top Pistons At Zero Deck (found Out 3 Days Ago). Thats The Story Rumble360, I Got Hit With The Power And Go Fast Bug, And I Like It. Next Time I Will Try And Give Better Detail In Asking Questions Thanks Newatthis
 
..............The bigger bore [4 inch] of the 302+327 really helps.... coupled with their short stroke.....+they r higher compression..........kim......
 
I'm sure the bigger bore helps. Unshrouding the valves, extra compression and all that.

Here's what I was originally looking at and thought might be fun...

Take my stock '71 318 (3.91 bore and 3.31 stroke)

Put on a set of the Edelbrock Magnum heads (58 cc chamber), and Eddy RPM Air Gap intake.

Use a Mr Gasket head gasket (4.140 bore, .028 compressed thickness)

ASSuming a worst case that my pistons are .080 in the hole (though the spec is .050), my numbers come up with a theoretical 9.14:1 compression ratio, which is a smidge higher than a stock 5.0 Ford. If they are .05, it would actually be 9.7:1 !!

These numbers would be reduced slightly if there are valve reliefs in the piston, or if the top ring is way down from the top of the piston.

Couple that with a RPM Air Gap and a well chosen camshaft to preserve dynamic compression (I think some of the Voodoo cams have a quick Intake valve close) and you might just be able to make some decent numbers with what would normally be considered a boat anchor.

Of course, the real downside to lower cubes is that you have to spin it higher to make the power, which means more gear, more converter, etc. and you don't get that torque off-idle like you do with the higher cubes, which is what makes them fun on the street.

I've got the heads, my Dart's original 32,000 mile 318, TTI exhaust, and the RPM Air Gap. I'm really tempted to try this out instead of bolting the parts on my 5.9 Magnum, just to see what happens, but since I've already spent the scratch on the Magnum, and a custom cam and oil pan for it, and I'd have to pull the 318 to seal it anyways (aka it leaks everywhere), its kind of hard to justify, though the 5.9 would keep. (I'd have to buy a cam, lifters, pushrods, and probably a balancer and oilpan).

It would also really suck if a 40 year old rod bolt lets go and trashes my high dollar heads! LOL!

Steve
 
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