best carb for a 440

I have a 67 gtx with a 440 with 440 source heads and 10.1 compression it has a 557 lift soild mopar cam and a m1 intake 4:56 gears rarly driven on the street what would be the best carb thanks for the help.

Sounds like maybe 550 hp type engine so I'd go with a 750DP carb. An 850DP might make a little more top end power.

You could contact BradH and offer to do some carb testing for him. Might be a win/win for you guys!

Quick fuel "Q-850".
Those have the 1.750 throttle bore with a 1.400 Venturi.

I have a 500HP 440 in my 71 Cuda. Old school set up with 520 hyd Racer Brown cam and Holley SD. I own both the 750 and 850 DP. Playing with both jetting, they are so close it was no longer worth my time swapping back and forth.

If you have a choice--the 750DP will be better. Chuck Lofgren verified this when he was running his 70 440 Cuda at BIR.

Provided you are in the old school build type.

850 dp minimum imo.............

the right foot determines how far the throttle plates are opened, even at WOT
Every Mopar B or RB motor I've palyed with loved more air and fuel, even sixpaks or tunnel rams

I agree with ^^ these guys as well and 850 will allow you to make a few other mods to the engine retaining the carb.

One thing no one has asked.. is this a trans brake
or foot brake car.. a trans brake can use a big carb
but a foot brake car you have to have good throttle
response to get the rpm... I was running a 1050 on
a 405ci but with a trans brake

My 440 has run best using a 750 Holley DP carb.The 850 didn't work as well.

I have an 850 Speed Demon on a very similar combo. It starts, runs and drives flawlessly. Very happy with it.

My own experience would suggest you'll be leaving a LOT on the table with a 750. My 451 has an 830DP on it and it runs pretty good on the street, but I suspect it could be making more power up top at WOT with a bigger carb. OP is running 4.56's and an M1, both of which want RPM's. I would be thinking 850 minimum, larger (4150 -1000) would likely make more power and be my choice, especially for a car that is used almost solely at the track as the OP describes.

The smallest carb I'd run on a healthy 440 would be an 830.

If it really is not driven much on the street, and mostly a track car, then use a big carb. I like the 950-1,000 HP type with annular boosters.

I took a 950 off my little 318 and put on a 750, slowed the car down a tenth. Picked it right back up putting 950 back on.
So with a bigger motor I suspect the results would favor a bigger carb

i just picked up an 830Hp 4150 for cheap, then started doing some reading, it has the 1.56" venturi.

i would maybe look for a holley 950DP, as the venturi is smaller than the 830 and 850 holley carbs, might work better.
maybe consider picking up a clean used one (any of the above ^) and send it to Thumprdart to get adjusted...

Years ago I ran a 850DP on a very mild 440 and it worked great. My 434 small block has a BLP main body with 1.590" venturi on a holley 1.75 base plate and works great for street/strip, according to BLP it's 1050-1100 cfm.

Ran an 830 DP years ago on a mild stock bore 440 with a 528 flat tappet purple cam. 10.1 compression and it ran great on the street and track at 3600 + lbs.

I'd think that you would want to run an Edelbrock carb on your setup since they weigh a lot less than a Holley. (although the newest all aluminum Holley carbs are getting to be fairly lightweight)

I surely wouldn't recommend a carb based on weight and NOTHING including efi out performs a Holley carb in single and dual applications.........

Andy.

That was before I got the 1 Flu over the cuckoos nest weight loss sickness.

Not sure what the lightest carb is that would still have decent performance. Thermoquad maybe? QJet is probably fairly light. Maybe need to do a weight vs. power shootout to pick the best carb for you.

I agree. 5 pounds is extremely unlikely to be seen on a time slip, and unimportant on a street strip or bracket car in the whole scheme of things. And that's if there is even a 5 pound difference.

Thanks for the help I found a 850 xp on ebay and I am going to try it Thanks again Matt.

One thing I have read is how well the fuel is atomized for various intake temperatures is very important? An X plain intake without heat may want very good atomization, a heated dual plain might suffer from it. The same might apply for the same intake, heat versus no heat in the intake regardless of manifold.