Cast iron intake/exhaust manifold porting??

Good for you! I’m stoked to follow it along. (I don’t want to jinx myself but I may have just made a long-coming job switch and will be able to put my plans in motion too)
 
Turboomni said:
That is my main concern now and is why I am considering a roller cam . What are your thoughts and or experiences on this concerning exhaust manifolds?
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To be honest, I don't have any problems using manifolds when three facets of a build align:
  1. The customer has to have an expectation of output (read that as power level or performance expectation) that can be reached by their use.
  2. The customer understands that some compromises will have to be made in order to accomplish #1.
  3. The customer has the funds to properly build an engine to the level of #1.
If either of 2 or 3 are not met, 1 won't happen. The rest is simple physics as Scotty might say. You need air in and out to make power. We know how much we need. So you have to equip the engine with the components that allow for that volume. If you don't, it won't make the steam. Simple as that. If you're thinking the old adage "Fast, cheap, good. You can have any two." You're right. I'll add you need to use a builder that can do what you want... and frequently that means mean more money - for labor, maybe for parts, more time and gas getting to them, or more faith and freight costs if they are not local.
The internet is fun but a lot of what you read is not directly applicable to what an individual wants to do. Your roller cam comment sounds like a direct result of that sort of thing.

So the same questions I ask every time:
What's the engine going in?
What do you want the car to do?
What sort of driving/usage do you want from this car?
What things do you hate about other cars?
What do you have to start with?
How much money do you have to spend (be honest with yourself)?
When do you want this all done?
 
Turboomni said:
I am going to do the bottom end and heads right. Intake and exhaust manifolds and cam are easy access later for improvements compared to engine removal. First things first getting the block to my machinist next week to see if all is well with the block.
It seems to me if you take a stock 440 in this case and do nothing else but stroke it ,the engine will make more torque at a lower rpm than the stock motor. The stock heads and manifold and carb will choke it sooner in rpms because of the bigger displacement. Fine ,if the after market aluminum heads flow more than stock then all I have to do is either upgrade the intake or go to headers or both at a later time to satisfy me. If a different cam so be it. But the bottom end at least is ready to do what I want. I have planned to start with stock rockers.
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All I can say in summary is "Sort of". Answer the questions and be honest...
 
70bigblockdodge said:
I'm telling you the stock intake is not horrible. The Mopar performance M1 dual plane was a aluminum version of the stock 73 up spread bore intake. Round some corners, get rid of the sharp edges and port matched the intake and it will pull to 5500-6000 on a strong 440.
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OK this is the manifold [intake] from my core motor . It is a 73.Is this the manifold you speak of 70bigblockdodge?

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I read up on this on FBBO and this is what they do to it for better performance with this 73 manifold. What do you think as I would like to use an Edelbrock also.

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They told me also my 69 intake was not good at all and the 73 is the way to go like you said 70bigblockdodge.

the 69,

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Here is the FBBO link from post #50

1968 440 with stock manifolds (cam selection help.)

Do you agree with the manifold choice and the mods to it?
 
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More pics of the modifications they made.

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The port job that has been done to the '73 manifold got rid of the stock port dividers and has converted it to a single plane configuration in part (the top part). This will increase the flow but rather than hack up a good stock manifold, why not just go to a T-7 Eddy if a single plane is what you want. The T-7 has better flow characteristics on the top end for your stroker build. You will sacrifice some low end torque but that will not be much as it will be more than compensated for by the increase in displacement. You will also have a much better horsepower gain above about 2500 rpms because of the better flow. Strokers need as much air and fuel in and as much exhaust out as you can afford along with a high performance cam sized to the increased displacement. I suspect you can also buy the T-7 for about the same price as the port work will cost you on the '73 manifold.

Dave
 
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Thanks Dave. I am not for or against the mod but now understand what the mod does. So I could do nothing to the manifold except add the adaptor plate to use a standard Edelbrock/Carter carb and keep it dual plane? I am worried about hood clearance issues with the T-7
 
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Turboomni said:
Thanks Dave. I am not for or against the mod but now understand what the mod does. So I could do nothing to the manifold except add the adaptor plate to use a standard Edelbrock/Carter carb and keep it dual plane?
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You could do that. You could also go with one of the after market thermo quads and not need the adapter. You will still be fighting trying to get enough air and fuel so that you get the most out of the stroker build. Stock manifolds are designed for street use to develop good low end torque to move a 4500# beast from a standing stop. You are throwing a wrinkle into that concept with the increased displacement as the stock carbs and manifolds were designed for optimum performance with the 440cid displacement. Going to 490cid throws that calculation out of whack and will leave the engine hurting for enough fuel and air in, especially at higher rpms.

Dave
 
Turboomni said:
Thanks Dave. I am not for or against the mod but now understand what the mod does. So I could do nothing to the manifold except add the adaptor plate to use a standard Edelbrock/Carter carb and keep it dual plane? I am worried about hood clearance issues with the T-7
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I like the mod. I agree with Dave somewhat. On a small displacement engine 383/400 using a single plane which is quite different than a dual plane will really kill the bottom end <3500. A dual plane with the center out is still a long runner intake with more plenum area at the center under the carburetor. The Eddy rpm is a kick *** intake, I have a ton of grunt down low and it spins higher than I want to push my cast pistons. The mod heads a stock intake in that direction and I would say it will not hurt a bit especially on a mellow stroker.
I approve of this modification.
:thumbsup:
 
Seems like a good choice,,,I didn't see it in your link though,,is there a different name?
I figure if I dump the money into the block and heads most other things I can get to without pulling it later.
 
The DP4B is the one they tested. The CH4B is the proper name for the 440 version. They have a typo and call it a C4B.
 
Oh ok Got it. :thumbsup: I'll check it out.
 
Looks real good!! Congrats!

Edelbrock Dp4b
Surprise! The oldest design produced the best average power of the dual-planes-of course we’re only talking 1-3 numbers better, and that can be testing variance, but still, this thing wasn’t at all bad. It’s the first of the Mopar aftermarket dual-planes but has not been sold in many years. The DP4B designation means Dodge-Plymouth 4-Barrel, and the C4B (Chrysler 4-Barrel) is for 440s. This intake is most like the stock design, with the smaller of the two planes on the right side and feeding cylinders 2, 3, 5, and 8. The coil bracket is not in the stock location, but even so, many people who want an OE look use this manifold.

Price: Ours was $104.39 on eBay, but maybe the price will jump now.





Manifold height: front 311/44, rear 411/48
Peak torque: 456 lb-ft @ 3,800
Peak horsepower: 445 hp @ 5,900
Power at 3,000 rpm: 419 lb-ft, 239 hp
Power at 5,000 rpm: 431 lb-ft, 410 hp
Average 2,500-4,500: 429 lb-ft, 289 hp
Average 4,500-6,000: 419 lb-ft, 417 hp
Average 2,500-6,000: 424 lb-ft, 344 hp
 
I have literally no extra room under my hood. There’s an impression of the air cleaner in the hod pad. I may need to scrape back every quarter of an inch I can get. If that’s the case, I may end up with an action plus.

There is also a RB shootout somewhere. They start with factory cast iron and do lots of other options. Down side is their mule has a lot of cam.
 
bajajoaquin said:
There is also a RB shootout somewhere. They start with factory cast iron and do lots of other options. Down side is their mule has a lot of cam.
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Where? Nick's garage perhaps?
 
Probably Mopar muscle. It’s in article form, laid out very similarly to the one I linked. Let me see if i saved it on my computer.
 
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