Heads, how much gain?

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mopower440

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The engine in my dart is a 1975 440:
.030 over
Trw L2355 six pack pistons
MP 284/484 cam installed 2 or 4 degrees advanced. (cant remember, been a while)
Bone stock 452 heads
Compression is 9.4:1
Stock intake
Demon sizzler thermoquad
Hooker 1 7/8 fenderwell headers
3000 stall convertor.

Thinking of getting some heads. I would not be able to afford any porting to the new heads so they need to be good flowing right out of the box compared to my stock 452 heads. SO, if i got a set of new edelbrock heads or something similar, what kind of HP and torque gains could i expect? They say the edelbrocks and all these other heads right out of the box outflow the stock heads ported to the max...Is that true?
 
Lets start by saying "nothing" is ready right out of the box. That being said if you buy brand new eddy's you will need to have them checked, they are mass produced and sometimes things get done badly. Have a machinist check everything before running them, If you buy rebuilt mopar iron heads go with 906's and I have a guy that sells rebuilt 906's with stainless valves and whatever springs you need for your cam, 5 angle valve job for really good prices, I am running a set of his 360 heads on my 340. Here is the link, his 906's stat at $599 and he has upgrades to your specs. He also sells eddy's for $1399 both assembled heads

http://www.aeroheadracing.com/id6.html
 
Take my advice and everybody else that says eddy heads are NOT ready out of the box!! I have an active thread about the issue I am having with my eddy heads that I just put on out of the box.

The heads need a valve job, and pretty bad, I am losing compression due to the valves not sealing, they can be good heads with some work though.
 
Yes I would have them checked. What I mean is performance wise out of the box compared to my stock heads. Also by out of the box I mean thazt what they flow out of the box because I wouldn't have the money to port them also.
 
IMO, it won't be worth the trouble to BUY the heads, have them checked AND corrected if you are not going to port them. I cannot see 1500-2000 bucks worth of power without port work, because that's about what you will spend. Spend for a GOOD port job plus getting them corrected and I say go for it.
 
RustyRatRod said:
IMO, it won't be worth the trouble to BUY the heads, have them checked AND corrected if you are not going to port them. I cannot see 1500-2000 bucks worth of power without port work, because that's about what you will spend. Spend for a GOOD port job plus getting them corrected and I say go for it.
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Damn. I thought I read that out of the box aftermarkets outflowed a fully worked over stock head. Maybe I would be better off just using the money to have my stock heads ported and all.
 
mopower440 said:
Damn. I thought I read that out of the box aftermarkets outflowed a fully worked over stock head. Maybe I would be better off just using the money to have my stock heads ported and all.
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I never said they didn't. I said IMO, it's not worth the difference unless you have them properly prepared and ported. If they only flow say 15% better than what you have now, how is that worth it?

Maybe Jim Laroy will chime in and give some specifics. I just threw 15% out as a basis for comparison. I do know that the heads never flow what they advertise out of the box. Never. Sometimes not even close.
 
I have been on the fence with the same decision. It is a tough call.
If a guy had a 1500. to 2000. budget would your money be better
spent on having a new set of aluminum heads checked over?
Or putting that money into larger valves and some porting on the heads
you already have.
I believe it really depends on what the guy doing the port work can deliver
more than any other factor. In the right hands iron heads can be made to
perform very well. It is a art form though. I have always felt with a iron head engine,
seemed it ran more crisp for lack of a better word.
The aluminum heads would give you a weight savings for sure. They come
with the larger valves already installed also. The ports untouched will make as
much power as a mildly ported big valve iron head.
So the aluminums does make it easy for a guy to bolt on some extra power.
For a guy that has the time tools and know how to port a iron head it could have
a great advantage when it comes to dollars spent per HP gained.
I think for most of us it is hard to beat the aluminum heads. If for some
reason you wanted more out of them later you could always have them ported.
 
mopower440 said:
The engine in my dart is a 1975 440:
.030 over
Trw L2355 six pack pistons
MP 284/484 cam installed 2 or 4 degrees advanced. (cant remember, been a while)
Bone stock 452 heads
Compression is 9.4:1
Stock intake
Demon sizzler thermoquad
Hooker 1 7/8 fenderwell headers
3000 stall convertor.

Thinking of getting some heads. I would not be able to afford any porting to the new heads so they need to be good flowing right out of the box compared to my stock 452 heads. SO, if i got a set of new edelbrock heads or something similar, what kind of HP and torque gains could i expect? They say the edelbrocks and all these other heads right out of the box outflow the stock heads ported to the max...Is that true?
Click to expand...

First, nope, Edelbrock RPM heads do not out flow stock heads ported to the maximum. But for your purpose that should not matter.

To your question about horsepower and torque improvement. I do not have a stock head to an OOTB RPM head test but the following dyno results would be similar. Here we have a low compression 440 using a MP 509 camshaft where we switch from a pair of stock 906 heads to a pair of mildly ported 516 factory heads. The 516 heads out flow the RPM head a little in the lower lift ranges but the horsepower increase in switching to the RPM should be similar. Post line #43 shows the dyno run previous to the head switch and #44 shows the increase with the head switch.

http://www.forabodiesonly.com/mopar/showthread.php?t=249866&highlight=low+compression+dyno+440&page=2

Here is a 440 shortblock very similar to yours with cylinder head and camshaft changes done on a dyno.

http://www.forbbodiesonly.com/moparforum/showthread.php?64775-Pop-s-440-is-near-ready-to-dyno&highlight=pop%27s+440

As others have cautioned, the Edelbrock or any other head should be checked and prepped before use.

I can email you OOTB head flows of stock heads and RPM and Stealth heads and compare them to ported iron heads but for some reason I can't download them on the forum.
 
do your home work and find which ones flow the best from where the valve starts to open up to total lift of your cam. when you make your choice take them, pour some mineral spirits down each port, see if any leaks out into the chamber. if not you are good to good. if one or a few leaks a little get yourself some lapping compound and a hand lapping tool and lap them in. if you can't get it to stop leaking take the head or heads to a shop have them do it on a machine like the others have suggested. oh, and get an aluminum intake while you're at it. that should remove about 100lbs off the nose.
 
It's good practice to have them checked and corrected. You can now buy barea castings, or assemblies, so if you can work with a local guy who's good you should be able to get out of them for less than $2200 ready to run. You also need the right gaskets and the right head bolts - so be aware of that. In terms of out of the box performance - with a good valve job the RPMs will outflow factory iron by 5-8% depending how good your iron is. A decent amount of that it low lift flow, so I'd expect some gains - feelable gains - with no other changes. plus you're taking 80lbs off the nose which will give more of a punch to the car with no additional power. In terms of power numbers - around 4-5% would be what I expect assuming not other issues and solid tuning. Your results may vary...lol.
 
Here, let's try this. All stock intake flows from the same bench.......oops, added ported 452.

Lift...........RPM...........Stealth...........452...........ported 452

.100..........73..............66.................61.............90
.200.........146............142...............130............166
.300.........209............205...............188............218
.400.........254............240...............213............255
.500.........276............255...............227............278
.600.........287............267...............230............288
.700.........291............268................................294
 
I have been a long time flag waver of porting your iron heads for a more than likely cheaper cash out lay and better results than a new set of aluminum heads, which rarely come good to go.

A lot of this is based on the performance level your looking to achieve. What is it exactly your trying yo do? How fast do you want to go? And of course, where do you want to do it? Going fast at the track is far different than going fast in the street. The build changes.
And the cam, converter, rear gears etc... well, that is a big part of the build.

I've seen guys run mid 11's with OE iron heads. So going fast is possible with iron heads. BUT, the rest of the build, the way it is combo'd together is not what I would call a street friendly combo.

You do not need "High flow" aluminum heads to go fast. You need a well thought out combination.
 
As an addition to the other heads flows........we have iron head flows bordering on the insane.

Lift..............906 IN/EX ported to the max, no welding and no epoxy and using 2" ex tube

.100...............89/60
.200.............161/129
.300.............212/185
.400.............257/216
.500.............297/234
.600.............331/253
.700.............347/264

Best to buy aluminum as these would cost way more than ported aluminum heads!
 
IQ52 said:
Here, let's try this. All stock intake flows from the same bench.......oops, added ported 452.

Lift...........RPM...........Stealth...........452...........ported 452

.100..........73..............66.................61.............90
.200.........146............142...............130............166
.300.........209............205...............188............218
.400.........254............240...............213............255
.500.........276............255...............227............278
.600.........287............267...............230............288
.700.........291............268................................294
Click to expand...

Before you put any money into a stock head take a good look at this chart. /\ /\ /\

Can you make HP with a iron head. Yes. Is it easier with a aluminum head? Yes. Is it cheaper, safer with more benefits in the long run? Yes.

Keep in mind aside from the HP gains you'll yield from a better set of heads, you'll also gain performance from having a lighter head.

You'll also have a head that can be repaired, a head that is less prone to detonation, a head that costs less to have ported if you decide to do that down the road.
 
I ran 10.50 at 126 with a out of box set of eddy 84 cc RPM head with a 11.1.1 440 in my 3500 pound 65 B-body plymouth. sounds like i might of left some on the table, but at the time i was broke and could not afford having them ported. thanks mopar65
 
my eddy rpm's for my 400 B were fine out of the box... the machine shop checked everything over. the only thing they did was slightly mill them to bring the comp up to 10:1 and make the intake match up better since they zero decked the block... but i was a lucky one.
 
well, would i be better off paying someone to port my 452 heads, or buy aluminum aftermarkets and run them with the stock ports and all, just have them checked? I want all i can get out of this thing as i have some chevy guys wanting to race.. I also need help i getting this thing to hook up. Its actually fairly quick as is but doesnt hook up. I want to do the inboard rear spring relocation kit and mini tubs so i can put some tire under it but i dont have a welder and cant weld anyway. I dont know anyone around here i could trust to pay to do it right..Thats the problem with owning a dart, not being able to get much tire back there..
 
Absolutely buy aluminum heads! Even indy ez have gotten affordable and they do everything better than stock iron. Look at cutaway shots of heads compared to irons! No comparison! Why spend tons of money on iron heads adding bigger valves and hours upon hours of porting when you can have incredible flowing heads that weigh far less! In my experience as I have eddys on my 11 second street car and indy 440-1's on my race car go with aluminum! ! Remember horsepower always starts in the heads! When the budget allows I would also ditch the old heavy trw slugs for much lighter je or srp or Ross pistons!
 
larger split pattern cam and edelbrock dual plane intake would give you much more gain,
your combo is lacking in these areas. imo
ported aluminum heads will provide minor gain with current combo
 
fishmens67 said:
larger split pattern cam and edelbrock dual plane intake would give you much more gain,
your combo is lacking in these areas. imo
ported aluminum heads will provide minor gain with current combo
Click to expand...

well, the problem with the edelbrock performer RPM intake is that ive been told by many that it will not fit under the hood of a 440 dart. They say its too tall and cant fit the air cleaner..Is there another intake out there that will perform closely to the edelbrock that will fit?
 
mopower440 said:
well, would i be better off paying someone to port my 452 heads, or buy aluminum aftermarkets and run them with the stock ports and all, just have them checked? I want all i can get out of this thing as i have some chevy guys wanting to race.. I also need help i getting this thing to hook up. Its actually fairly quick as is but doesnt hook up. I want to do the inboard rear spring relocation kit and mini tubs so i can put some tire under it but i dont have a welder and cant weld anyway. I dont know anyone around here i could trust to pay to do it right..Thats the problem with owning a dart, not being able to get much tire back there..
Click to expand...

Just my opinion - ported iron is simply a waste of money unless a sactioning body mandates them. The possible exception might be the closed chamber 516s or 915s and a goal of less than 1.2hp/inch (530hp in a 440). You're paying to get a port but sacrificing weight and a modern chamber. Both of which can be exploited successfully to make better usable power, and helping the economics of aluminum make more sense. You also end up having to revamp the rest of the combo once you have decently ported heads in order to take advantage of them - so leave money on the table for that too.
That being said - if you can't hook it now - ignore anything to do with making more power and do the chassis work. You'll get more from dropping $2K on a chassis work and great race shocks vs anything to give you more power if your comment is true.
 
mopower440 said:
well, would i be better off paying someone to port my 452 heads, or buy aluminum aftermarkets and run them with the stock ports and all, just have them checked?

Aluminum. Ported or not apples to apples you'll have less money in them than the iron heads and less weight. You'll also have a repairable head. In OOTB form you can see they outflow a stock head. I run mine OOTB and they are fine, pass leak down and go 11.70's.

I also need help i getting this thing to hook up. Its actually fairly quick as is but doesnt hook up. I want to do the inboard rear spring relocation kit and mini tubs so i can put some tire under it but i dont have a welder and cant weld anyway. I dont know anyone around here i could trust to pay to do it right..Thats the problem with owning a dart, not being able to get much tire back there..
Click to expand...

Doesn't hook up on the street or at the strip? The strip is VERY different. Much stickier!

You don't need a mini tub to hook up at the strip. On the street the mini tub is going to help you hook up better and looks tough too.

You can fit a 26x10.50 under your car with nothing more than offset shackles. They have cars in the 6's on 10.50 rubber trapping speeds over 250mph.

The only thing that has to be welded for offset shackles is the new perches. Nearly anyone could do that for you.
 
The only time you run the iron head is if you must according to the rules or you think you just gotta have that iron head.
 
roccodart440 said:
Doesn't hook up on the street or at the strip? The strip is VERY different. Much stickier!

You don't need a mini tub to hook up at the strip. On the street the mini tub is going to help you hook up better and looks tough too.

You can fit a 26x10.50 under your car with nothing more than offset shackles. They have cars in the 6's on 10.50 rubber trapping speeds over 250mph.

The only thing that has to be welded for offset shackles is the new perches. Nearly anyone could do that for you.
Click to expand...

I thought you had to cut out a section of the frame rail and weld in those spring relocation boxes?
 
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