Couple Questions For 440 Motor

[Mastodon08]

Gentlemen, thank you for always providing me with good info and wisdom, looking for some advice on a couple probably pretty easy issues (to the Mopar veterans). Question #1: Should I use a cam thrust button for a flat tappet cam and question #2, what is the best cfm for the carburetor on a 440 that is bored .030 over with cam lift in the .494-.513 range? I was going to go with an 850 cfm...your thoughts?

Thank you and God bless,

Phil

[BLK 68 R/T]

Question 1: No, not needed on a flat tappet. Question 2: Without knowing the rest of your build? I see them everywhere from 625 edelbrocks to 950 Holley. Just depends on what you are doing with the car and how the engine is built. Probably a 750 will work just fine.

[John_Kunkel]

Most folks would recommend no bigger than 750 cfm.

Satan rules.

[Bad B-rad]

John, normally a 750 would be ok.

But I think Satan runs a 666pack.
and has had great results with that.

[Kern Dog]

Most folks would recommend no bigger than 750 cfm.

Satan rules.

What kind of bullshit is this?

[c00nhunterjoe]

Most folks would recommend no bigger than 750 cfm.

Satan rules.

What kind of bullshit is this?

I kinda thought the correct answer was throttle body injection. 

[John_Kunkel]

Most folks would recommend no bigger than 750 cfm.

Satan rules.

What kind of bullshit is this?

It's called a rejoinder, way over your head..

[Bad B-rad]

Not over my head, that's why I made the comment about Satan's 666 pack, or that its in his black Dodge Demon, with flame paint job.

[Challenger340]

The factory used a Carter AVS Carburetor rated @ 800 cfm  in 1969 on 440 Magnum Engines, I see no reason if using a Vacuum(or Airflow dependent) secondary style Carb to use any less cfm.  As mentioned, Flat Tappet Cams do not require a Thrust Button.
If you are currently on the process of Boring/Honing ? be very careful what Pistons you use, lest it won't matter what cfm Carb you use, Dawg = DAWG !
http://www.dodgecharger.com/forum/index.php/topic,118292.0.html

[John_Kunkel]

The factory used a Carter AVS Carburetor rated @ 800 cfm  in 1969 on 440 Magnum Engines

Oh? Where'd you get that number?

In reality, there are no officially published CFM ratings for most OEM Carter carbs, the usual guesstimates are based upon throttle-bore and venturi sizes compared to aftermarket units with published numbers.

[justcruisin]

I think it is pretty hard to beat a holley style mechanical secondary in a 750cfm with tunable circuits for a 440 street engine at or around the 500HP mark. I use a quick fuel but the proform is a good option and a little cheaper.

[Kern Dog]

Most folks would recommend no bigger than 750 cfm.

Satan rules.

What kind of bullshit is this?

It's called a rejoinder, way over your head..

Yeah, like anyone gives a shit. The Op was trying to be polite, your efforts were just the opposite.

[Nacho-RT74]

I just have to say... stock 70s BB TQ carbs are rated at 850 cfm ( all BB not just 440 ).

I'm not who tells that, just what I read

[Challenger340]

The factory used a Carter AVS Carburetor rated @ 800 cfm  in 1969 on 440 Magnum Engines

Oh? Where'd you get that number?

In reality, there are no officially published CFM ratings for most OEM Carter carbs, the usual guesstimates are based upon throttle-bore and venturi sizes compared to aftermarket units with published numbers.

I remember reading it somewhere once upon a time ? No pun intended to being a fairly tale......
Then 2 years ago while replacing a heavy float I threw my AVS 4618 up for shits & giggles, right about 780 cfm if I remember correctly ? Dunno if I was using a baro correction or not ?  but it was close enough that I just went with "verified" in my nogg'in at 800. (my old bean is like a failing hard drive, store only what's needed and the rest gets dumped)

I have to replace the accelerator pump soon anyways,(I should have done it 2 years ago but didn't) so I'll mount it up again and make a note to post it here.

It's interesting to "see" what different Carbs actually Flow, and I've tried different Air Cleaner bases also, but the SF750 Bench doesn't seem to have quite enough sensitivity ? or is right at it's limit for seeing small changes ? when using 20.5" H2O "up there" for accurate data, the Dyno still producing the best, and sometimes most surprising results.

[John_Kunkel]

The Op was trying to be polite, your efforts were just the opposite.

The OP was buying a step, I retorted.

[Challenger340]

A little off topic, but nonetheless relevant if we're talking carburetor "selection" versus "cfm" ?
On the Dyno we've found....
that if operating at any kind of elevation, or the customer INTENDS to, say starting 2,500ft to 3,000ft and up..... selecting a larger Carb cfm than actually "needed" from charts, is a beneficial way to CHEAT some extra power/airflow through the usually LARGER Throttle plates.
You just get more in.... period.... through the LARGER plates with the lower ambient air pressure, which seems to help the smaller Volume Ports like wedge Chrysler's.

Just my opinion,
but if you are running at 2,500 ft and up I'd go for a carb about 100 cfm Bigger than what most charts indicate, select one with 4 corner idle if you can, balance the plates, and if you get to a track for some fun then Jet it until it quits mph'ing.

[Mastodon08]

Satan aint gonna be ruling forever bro...God bless your soul...hope you change your mind before the end...

[alfaitalia]

Thought political and religious post were banned on here??? I don't care though......if you want to argue that your imaginary friend is better than his imaginary friend.....that's fine with me!!


.....oh....and by the way I've got some "magic beans" you might be interested in??

[Mastodon08]

I'm not arguing with anyone. With all due respect I've had more than enough experience with both sides enough to know the reality of spiritual existence. It's a matter of the heart. Seek for yourself and then tell me if it's imaginary. A cynical approach isn't gonna get anyone anywhere. Have a good day.

[c00nhunterjoe]

All i know is its trumps fault....

Muahahahaha.

In before the 

[BDF]

I'm not arguing with anyone. With all due respect I've had more than enough experience with both sides enough to know the reality of spiritual existence. It's a matter of the heart. Seek for yourself and then tell me if it's imaginary. A cynical approach isn't gonna get anyone anywhere. Have a good day.

I agree. Good luck with your carb selection & God bless you!

[John_Kunkel]

Satan aint gonna be ruling forever bro...God bless your soul...hope you change your mind before the end...

Hope you get that stairway built before the end.

[Bronzedodge]

Satan rules.

"I'm Anton Szandor LaVey, and I approve this message."

( obscure 70's reference) 
( Ya gotta give it to him, he LOOKED the part for sure. )

[Bronzedodge]

Sorry.  I like a good laugh as much as the next guy.

To the OP - as others said, you'll rarely need a thrust button with a big block.  If you're not going with high flow heads and deep gears, 750-780 cfm should be fine, max.  700 might be better.

[Mastodon08]

Thanks Mr. Kunkel...hope you get the stick in your rear fixed before the end.