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500cfm for a 440?

Posted By: Alexdodge

500cfm for a 440? - 06/08/08 11:11 PM

Will a 500cfm eddy carb be to small for a 440 street car? I had two of these on the shelf from a previous dual quad setup. Would it be worth going to a 600 or 750 eddy? With two like new carbs on the shelf, I hate to spend more money if there isn't much difference. Thanks All, Alex
Posted By: mark7171

Re: 500cfm for a 440? - 06/08/08 11:28 PM

i like the afb's...500 isnt goint to allow a proper idle. you can try it, and get it to work. but .

you like the 800-850 TQ? or a 750-800 edelbrock ?

if you like tunning carbs, try a holley. they are for people who like to tinker.
Posted By: AndyF

Re: 500cfm for a 440? - 06/08/08 11:46 PM

It will work pretty well for driving around on the street but you'll run out of air at WOT. Should be nice and crisp for street driving though.
Posted By: DaytonaTurbo

Re: 500cfm for a 440? - 06/08/08 11:49 PM

Or buy the edel dual quad intake to get some use out of them? But just one 500cfm'er?
Posted By: dave571

Re: 500cfm for a 440? - 06/09/08 12:19 AM

I'm conservative as far as carb size goes.
I even run a 625 road demon and my 440 tow rig winni, and find it is a great carb....

BUT 500 is way to small.

I remember I had a 600 eddy on a 400 with some mods. Threw on a 750, and saw a 30 wheel hp gain on a g tech.

I agree with running both.
Posted By: Alexdodge

Re: 500cfm for a 440? - 06/09/08 12:40 AM

Thanks guys, Guess I'll just order a 750 or 800 eddy and be done with it. I'll save the 500's for the 440 I plan for the 62 Polara that I'm restoring Alex in Ohio
Posted By: Anonymous

Re: 500cfm for a 440? - 06/09/08 12:48 AM

850 DP
Posted By: scotts66charger

Re: 500cfm for a 440? - 06/09/08 04:11 AM

A good running 440 will love a 750 DP. Your choice of makes. IMHO, anything less than a750 dp will cause your 440 to stumble and fall when you floor it, as it screams for more gas. scott
Posted By: Supercuda

Re: 500cfm for a 440? - 06/09/08 04:15 AM

Quote:

A good running 440 will love a 750 DP. Your choice of makes. IMHO, anything less than a750 dp will cause your 440 to stumble and fall when you floor it, as it screams for more gas. scott




Yeah, that's why the factory put a double pumper on every 440

IMO, a double pumper is a great way to waste gas on a street car.
Posted By: Anonymous

Re: 500cfm for a 440? - 06/09/08 04:54 AM

Quote:

Quote:

A good running 440 will love a 750 DP. Your choice of makes. IMHO, anything less than a750 dp will cause your 440 to stumble and fall when you floor it, as it screams for more gas. scott




Yeah, that's why the factory put a double pumper on every 440

IMO, a double pumper is a great way to waste gas on a street car.




DP's work awesome on the street. stay outta the secondaries and its no problem.
BUT if one wants the best carb for a STREET app.. its the CARTER TQ.
Posted By: DaytonaTurbo

Re: 500cfm for a 440? - 06/09/08 05:19 AM

Quote:


DP's work awesome on the street. stay outta the secondaries and its no problem.
BUT if one wants the best carb for a STREET app.. its the CARTER TQ.




TQ is a great street carb for the money. Best bang for your buck. But if you want something new/square bore DP would be my carb of choice. Every carb wastes a ton of gas once you get into the secondaries, regardless of whether it's got an extra pair of squirters back there or not.
Posted By: 340SHORTY

Re: 500cfm for a 440? - 06/09/08 09:32 AM

Quote:

A good running 440 will love a 750 DP. Your choice of makes. IMHO, anything less than a750 dp will cause your 440 to stumble and fall when you floor it, as it screams for more gas. scott


Posted By: Mr.Yuck

Re: 500cfm for a 440? - 06/09/08 12:58 PM

Quote:

Quote:

A good running 440 will love a 750 DP. Your choice of makes. IMHO, anything less than a750 dp will cause your 440 to stumble and fall when you floor it, as it screams for more gas. scott




Yeah, that's why the factory put a double pumper on every 440

IMO, a double pumper is a great way to waste gas on a street car.



How's that?? when they are tuned right they work better than any 750 on the market. Waste of gas and 440? like you're gonna run a 440 and expect good milage? As long as the carb is tuned it will do fine as soon as you crack the 2ndaries any carb is going to eat gas.
Stock 67 440's came w/ a 625, that's about as small as I'd go.
Posted By: buildanother

Re: 500cfm for a 440? - 06/09/08 01:31 PM

I think the last thing a 500 cfm carb would do on a 440 is bog, but that is a little small and may be better suited for a tow vehicle 440.
Posted By: dogdays

Re: 500cfm for a 440? - 06/09/08 02:10 PM

The amount of misinformation on this board about carb sizing is staggering. Any performance carb will supply "enough gas" to mix with the air that can flow through the carb. The 500 cfm carb will support about 300 horsepower. That's using the rule of thumb of 0.6 hp per cfm.

Thousands of 413s ran millions of hours with two-barrel carburetors, pumping water and performing other industrial tasks. As I have said in a previous post my family car in the early '70s was a 2-barrel 455 olds which would run 90 in the quarter and would top out over 100 mph, the fastest indicated speed I ever saw was about 122 but the stock speedometer could have been lying too. (Growing up in North Dakota had its advantages in that there was hardly ever a cop around on the roads I drove.) The carb on that car was the larger Rochester two-barrel which I doubt flowed more than 375 cfm rated as a two-barrel carb, which would be about 265 rated as a 4-barrel.
Keep in mind also the thousands of dirt track racers using the Holley 4412 500 cfm 2-barrel, which would be 353 cfm rated as a 4-barrel.

Stick on a 500 instead of a 750 and you are leaving about 100 top end hp on the table. This power loss should all be above the torque peak. The car will run really strong until it "runs out of breath" which will be a disappointment but will not be accompanied by any expensive noises. Try it and see what you think. You can always buy a bigger carburetor later.

R.
Posted By: MoparforLife

Re: 500cfm for a 440? - 06/09/08 02:18 PM

Quote:

The amount of misinformation on this board about carb sizing is staggering. Any performance carb will supply "enough gas" to mix with the air that can flow through the carb. The 500 cfm carb will support about 300 horsepower. That's using the rule of thumb of 0.6 hp per cfm.

Thousands of 413s ran millions of hours with two-barrel carburetors, pumping water and performing other industrial tasks. As I have said in a previous post my family car in the early '70s was a 2-barrel 455 olds which would run 90 in the quarter and would top out over 100 mph, the fastest indicated speed I ever saw was about 122 but the stock speedometer could have been lying too. (Growing up in North Dakota had its advantages in that there was hardly ever a cop around on the roads I drove.) The carb on that car was the larger Rochester two-barrel which I doubt flowed more than 375 cfm rated as a two-barrel carb, which would be about 265 rated as a 4-barrel.
Keep in mind also the thousands of dirt track racers using the Holley 4412 500 cfm 2-barrel, which would be 353 cfm rated as a 4-barrel.

Stick on a 500 instead of a 750 and you are leaving about 100 top end hp on the table. This power loss should all be above the torque peak. The car will run really strong until it "runs out of breath" which will be a disappointment but will not be accompanied by any expensive noises. Try it and see what you think. You can always buy a bigger carburetor later.

R.


Posted By: moper

Re: 500cfm for a 440? - 06/09/08 04:10 PM

Quote:

Quote:

The amount of misinformation on this board about carb sizing is staggering. Any performance carb will supply "enough gas" to mix with the air that can flow through the carb. The 500 cfm carb will support about 300 horsepower. That's using the rule of thumb of 0.6 hp per cfm.

Thousands of 413s ran millions of hours with two-barrel carburetors, pumping water and performing other industrial tasks. As I have said in a previous post my family car in the early '70s was a 2-barrel 455 olds which would run 90 in the quarter and would top out over 100 mph, the fastest indicated speed I ever saw was about 122 but the stock speedometer could have been lying too. (Growing up in North Dakota had its advantages in that there was hardly ever a cop around on the roads I drove.) The carb on that car was the larger Rochester two-barrel which I doubt flowed more than 375 cfm rated as a two-barrel carb, which would be about 265 rated as a 4-barrel.
Keep in mind also the thousands of dirt track racers using the Holley 4412 500 cfm 2-barrel, which would be 353 cfm rated as a 4-barrel.

Stick on a 500 instead of a 750 and you are leaving about 100 top end hp on the table. This power loss should all be above the torque peak. The car will run really strong until it "runs out of breath" which will be a disappointment but will not be accompanied by any expensive noises. Try it and see what you think. You can always buy a bigger carburetor later.

R.








Especially with that misinformation part..
Posted By: AndyF

Re: 500cfm for a 440? - 06/09/08 05:32 PM

NASCAR guys make a ton of power with 390 cfm carbs, of course they have a few tricks but they are really 390 cfm carbs.

I think a 500 cfm carb will work just fine on a street driven 440. The power would be down a little bit at WOT but probably not more than 10 or 20 hp from a 750 or 850 carb. This is assuming it is a street motor with a mild cam and pump gas compression.
Posted By: mark7171

Re: 500cfm for a 440? - 06/09/08 08:07 PM

TQ arent cool, they'll never catch on.

the sportier carter would be the AVS.

the hollies DP750 on 440 will kick some butt. the 800 AVS will keep up, and is much easier to tune.

AVS has a longer pumpshot good for highway gears too. for cruising the avs wins.
Posted By: 69L78Nova

Re: 500cfm for a 440? - 06/09/08 08:31 PM

Ahem....THERMOQUAD!!! I happen to have a rather nice Thermoquad off of a 74 440 in good running condition that I am selling
Posted By: Anonymous

Re: 500cfm for a 440? - 06/09/08 08:31 PM

Quote:

NASCAR guys make a ton of power with 390 cfm carbs, of course they have a few tricks but they are really 390 cfm carbs.

I think a 500 cfm carb will work just fine on a street driven 440. The power would be down a little bit at WOT but probably not more than 10 or 20 hp from a 750 or 850 carb. This is assuming it is a street motor with a mild cam and pump gas compression.




their also runnin 358cid engines too. I don't think a comparison can be made.
they'll be the first to admit there down a butt load of hp with 390 Holley's.
Figure about 50+hp down when compared to 850cfm Holley. even with a "mild"
cam and pump gas.
Posted By: Simonic

Re: 500cfm for a 440? - 06/09/08 08:45 PM

check it out and see what happens
Posted By: Gary67

Re: 500cfm for a 440? - 06/09/08 08:46 PM

Quote:

I'm conservative as far as carb size goes.
I even run a 625 road demon and my 440 tow rig winni, and find it is a great carb....

BUT 500 is way to small.

I remember I had a 600 eddy on a 400 with some mods. Threw on a 750, and saw a 30 wheel hp gain on a g tech.

I agree with running both.



I'm of the same thinking..I have an 800dp on my 66, I had a larger carb to use but am sticking with the smaller one. I definately would do larger than 500cfm on a street car, but it doesn't have to be an 850 to run well either...
Posted By: Mr.Yuck

Re: 500cfm for a 440? - 06/09/08 08:50 PM

Quote:

TQ arent cool, they'll never catch on.

the sportier carter would be the AVS.

the hollies DP750 on 440 will kick some butt. the 800 AVS will keep up, and is much easier to tune.

AVS has a longer pumpshot good for highway gears too. for cruising the avs wins.



are you talking about the new 800 eddy? ummm it will not keep up w/ a good 750DP.
Posted By: Anonymous

Re: 500cfm for a 440? - 06/09/08 09:40 PM

Stick it on there! A Mopar six pack has a 350CFM center carb--that is the one you run on all the time UNLESS you floor it!--yea it is small and won't be as good as a bigger one when you kick it but I bet you would be amazed at the throttle response! Later when you find a deal on something else do it! AED in Richmond Va. builds one of the best DP Holleys for the $$---available from many dealers that discount them some and they come with AMAZING customer service
Posted By: mark7171

Re: 500cfm for a 440? - 06/09/08 09:43 PM

what does keep up mean ? it supplies fuel on demand, yes.

you burn Oxygen.

on a build that wouldnt require the dual pumps volume, it would win...
Posted By: Anonymous

Re: 500cfm for a 440? - 06/09/08 09:46 PM

one CANNOT compare a 6-bbl setup to a single four. BOTTOM line
is that a 500cfm 4-bbl is TOO small for a 440. but hey..
if you wanna give up 50+hp a very little fuel economy.. go for it.
Posted By: Anonymous

Re: 500cfm for a 440? - 06/09/08 10:46 PM

Yea--it is too small but I bet you could drive it from Canada to Cape Horn if you wanted to.
Posted By: Anonymous

Re: 500cfm for a 440? - 06/09/08 10:58 PM

sure. i could do it with a 125cfm one barrel too, or a 1050 dominator.
Posted By: Alexdodge

Re: 500cfm for a 440? - 06/10/08 12:45 AM

Well I put in an order with summit on Sunday evening for the eddy 800. After reading all these messages, hope I did the right thing.

Thanks all, Alex
Posted By: 4boxers4

Re: 500cfm for a 440? - 06/10/08 12:46 AM

Quote:

TQ arent cool, they'll never catch on.

the sportier carter would be the AVS.

the hollies DP750 on 440 will kick some butt. the 800 AVS will keep up, and is much easier to tune.

AVS has a longer pumpshot good for highway gears too. for cruising the avs wins.




W/ AVS! and best mpg, if some care. Performance is why I like it, mpg is nice side effect. TQ is ok.

there is an equation to determine proper cfm but obviously 2bbl's work(especially 3 of them!)
Posted By: mark7171

Re: 500cfm for a 440? - 06/10/08 01:21 AM

excellent thats what i have on my 440's action + top end... a edelbrock thunder AVS800. works great, i put the spring loaded high flow needle and seats in ,and checked the float level. the rods and jets are a snap to tune in. easier than a holley, but im more familiar with holley's. the carb is the best AVS unit i ve worked with.

make sure you know how to set the high idle on the choke and it will start right up.

the mechanical secondary kick in nicely on a 440.

my other 440 top end is a 750 SD demon on a RPM intake. that runs rich low, but fine top end.

i tried the dominator single and it was terrible on the street. ..nuff said.
Posted By: mark7171

Re: 500cfm for a 440? - 06/10/08 01:25 AM

the equation is bogus. it doesnt account for actual effeciency. it takes a standard and applies it to many.

most charts i see show a number thats 80% of what you really need.

my dart wants big carbs. i put a 770 street avenger on it with a stiff spring , and its happy. the 600 was too small ? the 600 edelbrock was alright, and responded better up top.
Posted By: 4boxers4

Re: 500cfm for a 440? - 06/10/08 01:36 AM

Quote:

excellent thats what i have on my 440's action + top end... a edelbrock thunder AVS800. works great, i put the spring loaded high flow needle and seats in ,and checked the float level. the rods and jets are a snap to tune in. easier than a holley, but im more familiar with holley's. the carb is the best AVS unit i ve worked with.

make sure you know how to set the high idle on the choke and it will start right up.

the mechanical secondary kick in nicely on a 440.

my other 440 top end is a 750 SD demon on a RPM intake. that runs rich low, but fine top end.

i tried the dominator single and it was terrible on the street. ..nuff said.




Are you saying your AVS (Thunder) doesn't work well with the Street dominator manifold? I always found it to be one of the best combo's out there. I have a manual tranny though so it is easy to launch.

Well the fact that there are some assumptions necessary is the reason to use the equation for volumetric efficiency as a guideline, but the equation itself isn't what I would call bogus. in a controlled environment, it carries some legitimacy. It just isn't that easy to control your street car.
Posted By: Simonic

Re: 500cfm for a 440? - 09/19/08 01:43 PM

[quote

IMO, a double pumper is a great way to waste gas on a street car.


Posted By: Mr.Yuck

Re: 500cfm for a 440? - 09/19/08 01:47 PM

Quote:

[quote

IMO, a double pumper is a great way to waste gas on a street car.







That's because you don't know how to tune it...lol
any 4bbl carb will be a waste if you foot is heavy. and why would you have a 440 and care about mpg's? FWIW I managed to get 13mpg hwy in a 67 coronet (440) w/ 3.91's doing 70.
Posted By: Simonic

Re: 500cfm for a 440? - 09/19/08 02:16 PM

Quote:

Quote:

Quote:

The amount of misinformation on this board about carb sizing is staggering. Any performance carb will supply "enough gas" to mix with the air that can flow through the carb. The 500 cfm carb will support about 300 horsepower. That's using the rule of thumb of 0.6 hp per cfm.

Thousands of 413s ran millions of hours with two-barrel carburetors, pumping water and performing other industrial tasks. As I have said in a previous post my family car in the early '70s was a 2-barrel 455 olds which would run 90 in the quarter and would top out over 100 mph, the fastest indicated speed I ever saw was about 122 but the stock speedometer could have been lying too. (Growing up in North Dakota had its advantages in that there was hardly ever a cop around on the roads I drove.) The carb on that car was the larger Rochester two-barrel which I doubt flowed more than 375 cfm rated as a two-barrel carb, which would be about 265 rated as a 4-barrel.
Keep in mind also the thousands of dirt track racers using the Holley 4412 500 cfm 2-barrel, which would be 353 cfm rated as a 4-barrel.

Stick on a 500 instead of a 750 and you are leaving about 100 top end hp on the table. This power loss should all be above the torque peak. The car will run really strong until it "runs out of breath" which will be a disappointment but will not be accompanied by any expensive noises. Try it and see what you think. You can always buy a bigger carburetor later.

R.








Especially with that misinformation part..


Posted By: dogdays

Re: 500cfm for a 440? - 09/19/08 09:43 PM

I'm such a stud!
R.
Posted By: BRawls

Re: 500cfm for a 440? - 09/19/08 10:40 PM

Quote:

Quote:

A good running 440 will love a 750 DP. Your choice of makes. IMHO, anything less than a750 dp will cause your 440 to stumble and fall when you floor it, as it screams for more gas. scott





A six pack screams on 2 barrels, until the outboarbs kick-in. You are only going to notice a small carb holding you back on the top end. Low end will be a blast to drive, it's not going to stumble if it's tuned properly.
Posted By: dOrk !

Re: 500cfm for a 440? - 09/19/08 10:49 PM

THIS topic deserves a one-liner ....... Better to be UNDERcarbed ...than over.
Posted By: DaytonaTurbo

Re: 500cfm for a 440? - 09/20/08 12:20 AM

Great job bringing this thread back from the dead guys.
Posted By: 451Mopar

Re: 500cfm for a 440? - 09/20/08 12:23 AM

500 cfm should be good on the 440 upto about 4,000+ RPM. Above 4,000 RPM the carb will restrict flow and hurt power output.
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