Street combo for stock 440

[EV2 GTX]

Hey everyone...

I'd like to swap out my stock heads, cam, intake and carb on my 440, but leave the bottom end as is. The car is a '70 GTX with an air grabber hood, that I want to leave as is, so hood clearance is an issue for intake/carb.

As far as the cam, I'd like something with a nice lumpy sound and will go with a mild stall if necessary. So the question is two fold....

1. Is there any value per horsepower in this type of upgrade?
2. What combo's would you guys recommend to wake up the 440 a little?


Thanks!! :grin:

 

[goose69]

Well this can go a thousand directions as far as suggestions. But I'm puting together a 440 for my '66 belvedere and have hood clearance issues myself but want an intake that'll perform well with my combo I have. I decided on a Holley street dominator intake because its a very low intake but still produces #'s that flow well from 1500rpm- the mid 6000 range. That's a broad spectrum there. But look into the write ups and reviews before deciding. The cam selection is a huge area also but other info is probably needed to narrow the search (needed vacuume, rpm range you wanna operate in, etc).
The heads are another area where there's many choices. I happen to stumble upon a set of worked over 915's for an incredible price. Otherwise I would have probably leaned toward edelbrock heads. The cost of a set is comparable to a set of rebuilt and worked cast iron heads that its usually a better deal to get the assembled edelbrocks, and they perform better to boot.
Comp cams has a good tech line that if you call and give them a run down of your car and potential motor set up they are good at giving camshaft suggestions. Don @ 4 seconds flat is another good person to bend his ear for suggestions. He deals with Racer Brown camshafts and he'll custom grind a cam for your motor without being outragously expensive.
Good luck with your motor.

 

[EV2 GTX]

Hey Goose, thanks for the reply, I agree there are many many combos to consider. I think the Dominator looks like a good option as well, they've been around forever and are a great choice for streetable power.

To be honest I was thinking there might be someone that has something up and running that is happy with their set up and could comment as well. With so many variables it's not an easy choice, that's for sure. I definitely think there are more options than ever before!! :reading:

Good luck with yours too Goose, let me know how it works out.

 

[EV2 GTX]

I see that you added to your first post....I thought the eddy's looked good too....I don't think I'll go after vintage heads for reasons you have already touched on. Thanks for the contacts, it's all a help for an informed decision....

Thanks again Goose

 

[goose69]

I did buy some assembled eddy heads for my 383 build but ended up returning and buying bare castings and loading them up ourselves due to fact the tolerances weren't quite where we wanted. But I believe under a most cases they would work just fine. Matter of fact there were a couple guys here that bought some fully assembled units and worked awesome pushing their 440's way up in the power numbers. I'll try & find their builds and comments & send a link.

 

[goose69]

Take a look at this thread titled "Legitimate Street Car ET's" . There are a lot of combos on there that are pretty budget oriented and even on the 11 & 12 sec. combo pages.

 

[Meep-Meep]

Number one wake up prescription to any engine is compression but you have to take the fuel in to account. In the 12 second combo thread you will find my 66 Belvedere 440 that runs pretty well for the few "trick" parts it has. A little compression, a little cam, free up the exhaust and off you go on the cheap.

Since you don't want to go into the short block to change pistons I would put on a set of 915 heads. They will bump the compression .4-.5 point and if you use a steel shim gasket that will buy you another .4 point of so over a comp gasket. I saw a rebuilt set for sale on this forum. I advise CC-ing the piston at TDC and the chambers so you know exactly what you have. That way you can better plan and adjust for the fuel used. Choose a cam that will give you 175 PSI of cylinder pressure. I have 190 PSI and it's a bit much for our crappy 91 gas.

 

[IQ52]

Go to ANY aftermarket aluminum cylinder head instead of factory cast iron (unless you can port them yourself) and use a GOOD aluminum intake intake (sorry about the Air Grabber) because the factory cast iron intake is an airflow disaster. If you have to choose between airflow and compression, go with the flow!

 

[Meep-Meep]

Go to ANY aftermarket aluminum cylinder head instead of factory cast iron (unless you can port them yourself)

If you don't kill your compression.

and use a GOOD aluminum intake intake (sorry about the Air Grabber) because the factory cast iron intake is an airflow disaster. If you have to choose between airflow and compression, go with the flow!

What good is adding more airflow when the purpose is to optimize efficiency from idle to maybe 5000 RPM on a low compression engine? I won't disagree that the modern aluminum intakes are a much better choice for producing power but my cast iron air flow disaster runs high 12's in a 3700 lb B body. Not the fastest thing on the road but plenty fast to cause driving excitement. And if you consider performance per dollar ratio while maintaining the OP's air grabber requirement it's a combo that's hard to beat.

 

[lewtot184]

Hey everyone...

I'd like to swap out my stock heads, cam, intake and carb on my 440, but leave the bottom end as is. The car is a '70 GTX with an air grabber hood, that I want to leave as is, so hood clearance is an issue for intake/carb.

As far as the cam, I'd like something with a nice lumpy sound and will go with a mild stall if necessary. So the question is two fold....

1. Is there any value per horsepower in this type of upgrade?
2. What combo's would you guys recommend to wake up the 440 a little?


Thanks!! :grin:

too bad you didn't get that 6-pak setup i had for sale here. it would have been a perfect fit, everything was there for a 70 b-body. it took me from 99mph in the 1/4 (stock 4bbl) to to a tick under 108mph in a 4060lb, 3.23 geared, t/a radial, 9.25:1 pump gas driver. you don't need a bunch of cam. good heads make a difference and they don't have to be aluminum.

 

[EV2 GTX]

too bad you didn't get that 6-pak setup i had for sale here. it would have been a perfect fit, everything was there for a 70 b-body. it took me from 99mph in the 1/4 (stock 4bbl) to to a tick under 108mph in a 4060lb, 3.23 geared, t/a radial, 9.25:1 pump gas driver. you don't need a bunch of cam. good heads make a difference and they don't have to be aluminum.

I know...I'm trying to forget that I missed your set-up, I could have used that for sure...I also have a date code 69 6 pack block, crank and rods...your set up would have gone great with that too.....and your price was great! :icon_hang:

The motor in the car now, is the original(re-built from the bottom up) so I may leave well enough alone and start a build from scratch...that's really the reason I wanted to liven up the top end only...I really don't want to hurt the orig motor by pushing it too hard...

I want to go in and look at the cam on this motor, so I thought that this would be a good time to think about top end as well...maybe I'll re-think this...ONCE AGAIN...

 

[EV2 GTX]

What good is adding more airflow when the purpose is to optimize efficiency from idle to maybe 5000 RPM on a low compression engine? I won't disagree that the modern aluminum intakes are a much better choice for producing power but my cast iron air flow disaster runs high 12's in a 3700 lb B body. Not the fastest thing on the road but plenty fast to cause driving excitement. And if you consider performance per dollar ratio while maintaining the OP's air grabber requirement it's a combo that's hard to beat.

Thanks Meep, some good points here...it could be a toss up with the heads though...from a $ perspective? By the time a guy finds the 915's and has them ported etc, the out of the box (eddy's for example) might be a better bang for the buck?

What's your thoughts?

 

[Meep-Meep]

Thanks Meep, some good points here...it could be a toss up with the heads though...from a $ perspective? By the time a guy finds the 915's and has them ported etc, the out of the box (eddy's for example) might be a better bang for the buck?

What's your thoughts?

The aluminum heads can put you money ahead if your iron ones need a ton of work. I have as much or more in my 915's as buying a set of 440 source heads and I did the pocket porting myself. But I have seven sets of 915's so might as well use them up! My only concern with bolting on a set of aluminum heads on a bone stock short block is you won't make up the loss of thermal efficiency with compression. As I understand it adding a half point will keep things equal as compared to iron heads. This is a question for the head guru's at Edelbrock where I'm sure they have answers backed by dyno runs. I'm just saying it's something to think about.

The six pack would have been great! My next move is to try one on my engine and see how that does. Maybe I'll try it this weekend :3gears:

 

[IQ52]

What good is adding more airflow when the purpose is to optimize efficiency from idle to maybe 5000 RPM on a low compression engine? I won't disagree that the modern aluminum intakes are a much better choice for producing power but my cast iron air flow disaster runs high 12's in a 3700 lb B body. Not the fastest thing on the road but plenty fast to cause driving excitement. And if you consider performance per dollar ratio while maintaining the OP's air grabber requirement it's a combo that's hard to beat.

If it is your wish to run a stock cast iron intake there is nothing wrong with that!

But what do you leave on the table horsepower wise?

What good is adding airflow from idle to 5000 RPM?

I wonder.

How much airflow can be added at what lifts?

Let's look at some airflow tests. All flows are from the same flowbench.

Test 1) box stock big block factory 915 cast iron head 2.08" intake
Test 2) box stock 440 Source Stealth 2.14" intake
Test 3) box stock Edelbrock RPM 2.14" intake
Test 4) box stock Indy EZ Standard port 2.19" intake
Test 5) box stock Edelbrock 440 Victor 2.20" intake
Test 6) LaRoy ported factory 906 cast iron head 2.14" intake
Test 7) same as (6) but with a 2806301 stock cast iron intake and a Carter 4401S AVS carb from a 1969 383 Road Runner
Test 8) Same as (7) but swapping the 2806301 iron intake for an Edelbrock 383 Victor intake

All flows are from the same flowbench. Pay particular attention to the flows in columns (7) & (8) and the lifts at which significant changes take place.


lift.....(1).....(2).....(3).....(4).....(5).....(6).....(7).....(8)

.100...63.....66......73......66......68......71......69......69
.200..137....142....148....127....141....150....131....143
.300..187....205....209....181....204....209....172....203
.400..216....240....254....232....246....257....187....234
.500..224....255....276....272....277....292....199....259
.600..232....267....287....299....305....315....203....273
.700..236....268....292....315....324....321....204....273
.800...n/a....n/a....n/a....n/a....334.....n/a.....n/a.....n/a

Hummm.............12 cfm difference, at .200" lift, between columns (7) & (8). THIRTY-ONE cfm difference at .300" lift and SIXTY (the big six-oh) cfm more flow at .500" lift. I dont care if you are at 8:1 compression, that is going to make whopping difference from idle to 5000 RPM! And you don't even have to change your camshaft or compression to get the flow increase! But......if......you......do, think of the power increase you will have then.

But wait.........that is a single plane and you are going to lose your bottom end torque!!!

Wanna bet? Ah, add 47 cfm at .400" lift = lose torque....uh huh.

 

[383man]

First thing I would do is pull a head and find out how far down the piston is at TDC so you can figure your comp ratio with the heads you want to use. Ron

 

[IQ52]

My only concern with bolting on a set of aluminum heads on a bone stock short block is you won't make up the loss of thermal efficiency with compression. As I understand it adding a half point will keep things equal as compared to iron heads.

This in an interesting point and a concern that many have. It brings many people to strange conclusions.

Take for instance the IRON vs. ALLOY head test in Chevy High Performance Magazine. There theory was that with identical heads, one cast in aluminum and one in iron, the iron head would make more horsepower because the iron head would retain the heat better.

So they used two pair of Motown 220 cylinder heads, one set aluminum and the other iron, both supplied by World Products. They both had the same combustion chamber size, port size and valve size. The aluminum heads had cnc'd combustion chambers and didn't flow as well as the iron heads so they had to do some blending of the seat insert into the port to get the flows more equal and never got the aluminum head to flow quite as good as the iron head.

They tried both sets of heads on the same 383 ci small block and found that the aluminum heads made an average of 8 lb-ft of torque more over the entire rpm range.

Their conclusion:

"We still believe the iron heads have the ability to make more horsepower than the aluminum heads, but we also think the difference is probably less than an average of 5 lb-ft of torque. Given this, the power difference is slight enough that other variables can contribute as well. In this case the two sets of heads were not identical enough to reveal the basic inherent advantage of the iron heads."

Translation: We just proved ourselves wrong, but we still think we were right!

In another test by Car Craft Magazine there was a similar test of aluminum vs iron heads on a 388 ci small block at 10.88:1 compression using Dart Iron Eagle Platinum Series and aluminum Pro-1's. They were testing the, "iron heads make more power because they keep the heat in the combustion chambers".

They cc'd the intake runners and combustion chambers and flowed the intake ports at Westech Performance Group and found them to be "functionally identical" with no "revelant variances" in flow. Flow charts were provided.

Both heads were run on 91 octane and liked the same spark advance.

And their conclusion:

"Can you guess what we learned? Zilcho! As in zero difference anywhere in the power or detonation characteristics of the iron vs aluminum heads. Even the optimum total timing was the same at 36 degrees. Regardless of coolent temp, rate of acceleration, steady state or through a sweep, the dyno curves for the two style of heads were identical. If anything we could squint and guess and mumble that maybe the aluminum heads were better by 2-3 hp. But the one thing we could never say is that the iron heads retained more heat and and made more power than the aluminum. Maybe it is different on some engines with a drastically different water-jacket design, but we'll stand up and say that the old bench-racing line just ain't true."

 

[godfatherofchry]

my Question is how fast do you want to go Or what do you expect to spend.then you can get a better answer if money is not a problem well that changes everything.I did a motor like you are describing for a guy put it in the car it ran 12:40s and he was pissed and it was basically a stock motor drive any were do anything kind of motor.....Artie

 

[EV2 GTX]

Well gents, there is a lot of good info here and as usual a ton of things to consider. There is a balance between all factors for sure and that's what makes this fun. As I eluded to previously, there are more options than ever.

I have no experience with the "out of the box" heads, of any kind, thus why I'm asking, but it does open a huge debate and as Artie says...."if money is not an object then that changes everything"...lol, how true.

Being a numbers engine I really would just like to work on the top end and keep hood clearances..just want to wake it up a little for a few thousand dollars. If I'm gonna get serious about horsepower/torque I'll do it on another build, from the ground up...sub frame connecters, chassis and up...not an option on my '70.

Artie.. could you post what you did to that motor that ran 12:40, to give us an idea what you did?


Thanks guys, I appreciate your input, as always!:headbang:

 

[Meep-Meep]

If it is your wish to run a stock cast iron intake there is nothing wrong with that!

But what do you leave on the table horsepower wise?

What good is adding airflow from idle to 5000 RPM?

I wonder.

How much airflow can be added at what lifts?

Let's look at some airflow tests. All flows are from the same flowbench.

Test 1) box stock big block factory 915 cast iron head 2.08" intake
Test 2) box stock 440 Source Stealth 2.14" intake
Test 3) box stock Edelbrock RPM 2.14" intake
Test 4) box stock Indy EZ Standard port 2.19" intake
Test 5) box stock Edelbrock 440 Victor 2.20" intake
Test 6) LaRoy ported factory 906 cast iron head 2.14" intake
Test 7) same as (6) but with a 2806301 stock cast iron intake and a Carter 4401S AVS carb from a 1969 383 Road Runner
Test 8) Same as (7) but swapping the 2806301 iron intake for an Edelbrock 383 Victor intake

All flows are from the same flowbench. Pay particular attention to the flows in columns (7) & (8) and the lifts at which significant changes take place.


lift.....(1).....(2).....(3).....(4).....(5).....(6).....(7).....(8)

.100...63.....66......73......66......68......71......69......69
.200..137....142....148....127....141....150....131....143
.300..187....205....209....181....204....209....172....203
.400..216....240....254....232....246....257....187....234
.500..224....255....276....272....277....292....199....259
.600..232....267....287....299....305....315....203....273
.700..236....268....292....315....324....321....204....273
.800...n/a....n/a....n/a....n/a....334.....n/a.....n/a.....n/a

Hummm.............12 cfm difference, at .200" lift, between columns (7) & (8). THIRTY-ONE cfm difference at .300" lift and SIXTY (the big six-oh) cfm more flow at .500" lift. I dont care if you are at 8:1 compression, that is going to make whopping difference from idle to 5000 RPM! And you don't even have to change your camshaft or compression to get the flow increase! But......if......you......do, think of the power increase you will have then.

But wait.........that is a single plane and you are going to lose your bottom end torque!!!

Wanna bet? Ah, add 47 cfm at .400" lift = lose torque....uh huh.

My point is you can make a good running engine without spending a ton of money on aftermarket parts, and since the OP's requirement was to keep the air grabber, I believe a solid 12 second car using factory parts is good news to him. Do more with less I say. I can also stand up and say the old bench racing line just aint true when the masses say factory parts are useless. I agree using the factory iron intake is leaving a lot on the table power wise but I used it for fun and to see what I could get away with. Oh, and what cam am I running? The MoPar .455" / 272 that I bet most people wouldn't use as a hood prop.

Air flow numbers are all good but the engine doesn't only see air when it's running. Wet flow is the real answer. You can cut away the top of the port and increase the air flow numbers but it won't do the performance factor much good. Or take a bad port design with a sharp left or right turn and hog it out until the air flow increases only to have the fuel particles separate somewhere at the turn. Finally you take a perfect head design and slap it on a low compression engine with a late closing intake valve only to blow off your cylinder pressure and not make the power you hoped for. Higher compression increases efficiency and power output.

There is another correlation to port efficiency vs cam timing. One can say that a very well designed port can get away with less cam thus provide better all around drivability. How else would I explain my old 72 Porsche 911 T that idled glass smooth with the mechanical fuel injection and pulled all the way to 6000 RPM? One reason would be the exhaust pulses alternating from bank to bank. It all must work together. Cam, ports (I & E), carb, compression, timing and fuel.

 

[Meep-Meep]

This in an interesting point and a concern that many have. It brings many people to strange conclusions.

Take for instance the IRON vs. ALLOY head test in Chevy High Performance Magazine. There theory was that with identical heads, one cast in aluminum and one in iron, the iron head would make more horsepower because the iron head would retain the heat better.

So they used two pair of Motown 220 cylinder heads, one set aluminum and the other iron, both supplied by World Products. They both had the same combustion chamber size, port size and valve size. The aluminum heads had cnc'd combustion chambers and didn't flow as well as the iron heads so they had to do some blending of the seat insert into the port to get the flows more equal and never got the aluminum head to flow quite as good as the iron head.

They tried both sets of heads on the same 383 ci small block and found that the aluminum heads made an average of 8 lb-ft of torque more over the entire rpm range.

Their conclusion:

"We still believe the iron heads have the ability to make more horsepower than the aluminum heads, but we also think the difference is probably less than an average of 5 lb-ft of torque. Given this, the power difference is slight enough that other variables can contribute as well. In this case the two sets of heads were not identical enough to reveal the basic inherent advantage of the iron heads."

Translation: We just proved ourselves wrong, but we still think we were right!

In another test by Car Craft Magazine there was a similar test of aluminum vs iron heads on a 388 ci small block at 10.88:1 compression using Dart Iron Eagle Platinum Series and aluminum Pro-1's. They were testing the, "iron heads make more power because they keep the heat in the combustion chambers".

They cc'd the intake runners and combustion chambers and flowed the intake ports at Westech Performance Group and found them to be "functionally identical" with no "revelant variances" in flow. Flow charts were provided.

Both heads were run on 91 octane and liked the same spark advance.

And their conclusion:

"Can you guess what we learned? Zilcho! As in zero difference anywhere in the power or detonation characteristics of the iron vs aluminum heads. Even the optimum total timing was the same at 36 degrees. Regardless of coolent temp, rate of acceleration, steady state or through a sweep, the dyno curves for the two style of heads were identical. If anything we could squint and guess and mumble that maybe the aluminum heads were better by 2-3 hp. But the one thing we could never say is that the iron heads retained more heat and and made more power than the aluminum. Maybe it is different on some engines with a drastically different water-jacket design, but we'll stand up and say that the old bench-racing line just ain't true."

The Chevy High Perf Mag test you speak of is possibly one of 118,000 results on the subject http://www.google.com/search?q=alum...s=org.mozilla:en-US:official&client=firefox-a I spoke to Chuck Lofgren about my HEMI build and he suggested being more cautious with compression on an iron head engine as compared to one with aluminum heads. All I'm doing is bringing up some apparently good points worthy of discussion and all I have to go by is advice from the guy with a lot of experience and a dyno. It may not make a hill of beans of difference as you suggest but what if it does?