Road Runner Nest

does anyone have a recomendation for a carb on a 440...right now it's a Holley 1850, which is only 600 cfm...it was a good carb, but all of the sudden it started not having the four barrels kicking in...does anyone know how those work, or would rebuilding it solve the deal? it's already been rebuilt, but i don't think rick did it very well...anyway, thanks guys...oh yeah, and what do you do to keep a 440 cool these days? electric fan? other ideas???

When I had a 74 Runner with a 440, I had a 4-core radiator and a Hayden Flex fan. The fan was a little noisy, sounded like a blower sometimes, but with that combo, she never overheated.

I think that carb's secondaries are vacuum operated. I guess just check to see if all the ports are clear, especially underneath. I don't recall which ports operate the secondaries, but also make sure any vacuum lines are routed correctly. A little bit bigger carb like a 750 with non-vacuum secondaries might be a good idea too.

Greg

26" 4 core radiator should keep it cool...just make sure you've got a fan shroud on it too. It's amazing how much of a difference that will make

i have a 17" flex fan and an aluminum dual 1"core racing radiator right now...i know i need a shroud...would just a bent piece of sheet metal work...that's what the generic ones from whitney's are...i have to do something, cuz there is way more bumper driving here than there is in rural iowa lol. i don't really know how that carb works...it's vacuum operated secondaries...what do u mean the ports...like where the vacuum hose runs from the distributor to the carb? idk, i thought about getting a bigger one and then maybe it would run better, because i think the jets are maxed out to run that 440...this is like a 350 carburetor, but it works...or used to lol.

thanks guys

I had that happen to me from the car sitting to long, the gas dried up in the fuel bowls and gummed up.I had to soak the meetering blocks in a tank of some nasty carb cleaner to clean the gum and you have to blow the holes with air. Also the vacumn secondaries can be adjusted, you buy a spring kit and you can make the secondaries open sooner.The springs are color coded.

on the secondaries...

those work fairly simple, if you have the throttle opened far enough to allow the secondary plates to move ( this is a mechanical linkage onthe drivers side) then as the velocity builds through the primary venturies(sp?) it sends a vacuum signal- through internal ports in the carb body- to the vacuum actuator to opent he secondaries.
The spring kit has @ 8 different springs.

although ona 440 you should have a 750 cfm if your contemplating perfomance. A 600 is too small for anything but stock.- well unless you have TWO of them

so basically, i should prolly take it off, clean the crap out of it and then maybe rebuild it...

landon1 wrote:so basically, i should prolly take it off, clean the crap out of it and then maybe rebuild it...

No, take it off, heave it as far as possible, and then go out and get yourself a 750.

ya i wish i could...the guy that rebuilt it put in racecar jets, so i think that's proby the only reason i'm able to punch out the numbers i do, cuz otherwise, there would be no way...i got a good laugh out of that one...maybe can geta core on ebay cheap and rebuild it...i'll have to look

Well, better yet, get yourself 3 twos! Ah, 1350 cfm of pure adrenalin! Of course, Dave would tell ya you're still 2 barrels short (ala Hemi's 2 4s)...

bruce wrote:Well, better yet, get yourself 3 twos! Ah, 1350 cfm of pure adrenalin! Of course, Dave would tell ya you're still 2 barrels short (ala Hemi's 2 4s)...

Ya...what does Dave know...6 barrels rule!

ya, i heard the six pack is a much better deal, cuz you're getting almost too much gas for the street (ha!) with dual quads, where the six pack gives power on demand plus you have some control...dunno though, cuz never driven either way...my car has a quad and the pickup has a single...what a joke!

What can I say, I know when I first put the six barrel setup on my Road Runner the 440 became a perpetual valve train weakness finding device. Oh boy, did she love to REV!

Now THIS one has pushrods as thick as my fingers! If I bend a pushrod on this one I'm DOING something!

We have a 1968 440 motor in our 1972 RR. We removed the Holley and intake and replaced it with a factory 1973 440 intake with ThermoQuad carb.

It was nothing short of INCREDIBLE how this change WOKE UP that 440! Fuel economy improved dramatically, pedal response is SUPER CRISP, and the 440 ROARS louder and stronger than it EVER HAS when you punch it!

Here's what it looked like right after we bolted it on:





For lots of info on Thermoquads, go to the undisputed KING of Thermoquads, Demon Sizzler's website: http://www.thermoquads.com

Good Luck!

so if i try to find a new carb is it better to go with a holley or a carter...i don't know much about either...the carb is something i still haven't gotten into...when i got the carb i was looking for people to hlep me, cuz i had never worked on anything before adn they all cringed when i said it had a holley. i'd like it streetable for as much mileage as possible, but still have the balls to smoke them flippin hondas...burned one so bad last week and the four barrels didn't even work...i hate rice grinders! lol