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Which Eldebrock for Stock 440

AA1 68 R/T

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Looking for folks who are using the new AVS2 carbs on their stock 440’s. Should I be leaning towards a 800 cfm or a 650 cfm? Thanks in advance
 
I've always been one to go bigger.....and that depends on what you expect from your engine.....
 
800 a few less CFM than a factory thermoquad. If you have a 650, might just as well mount a 360 under it.
 
800 a few less CFM than a factory thermoquad. If you have a 650, might just as well mount a 360 under it.

For future-proofing, I should have bought the 800, I'll give you that, but on my 440, the AVS2 650 is way more responsive than the 750 street demon I was using and night/day better than a previous EFI system the car came with. You put your foot down, it boogies.
 
Go for the 800 cfm. With the spring loaded secondary air valve, these AVS carbs are much more forgiving than an AFB. The air valve responds directly to however much air the engine can pump.
 
750 on my modified 440.

All about the tuning on an Edelbrock. Check out their tuning map and experiment with a few different jets.

Lots of help there depending on what you're looking for, throttle response, daily driver, racing, etc.

In my experience with them they never run as good as you want them to out of the box. Easy to change jets etc. So get to tuning.

Lots of possibilities.
 
The carb size should depend on the type of performance expected from the engine.

The 650 has an advantage over the 800 because it has smaller primaries that will give fantastic throttle response. So if you just want a cruiser, & particularly if it is a heavy car, the 650 would be best. Above assumes a dual plane intake.

If more high performance oriented, the 800 might be best. If a single plane intake, the 650 might be better to recover some of the soggy low end associated with SP intakes.

If you buy a Holley, keep the box & throw away the contents....
 
How much tuning have you guys done on out of the box edlebrock carbs? This motor is stock with stock cast iron intake.
 
The original AVS on a 375 horse 440 was around 750, I wouldn't put on anything smaller than that.
 
I always put one step (.003" ) larger jets in the secondaries, just 'cause I can.
 
If you buy a Holley, keep the box & throw away the contents....
We did many mods on many different engines from various manufacturers. And this proved to be the best, most versatile, responsive carb for street/strip applications. What prompts your comment about holleys ?
 
Below, for one: 17 hp more, 17 ft lbs more, & used less fuel doing it 625 AFB v 600 Holley.
A Holley 4150 carb can never be a responsive as a met rod carb because of the tortuous fuel flow path of the Holley PV system.

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First, maybe you should consider an Edelbrock rather than an Eldebrock.....

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The original AVS on a 375 horse 440 was around 750, I wouldn't put on anything smaller than that.
Good advice here ^^.
 
What prompts your comment about holleys ?
Usually from people that don't know how to tune them. The TQ got a bad rap for the same reason and it was mostly a very simple problem like the secondary air door opening too soon and causing them to earn the name Thermo 'bog'. So far it's the TQ that has has earned it's place in being the best street carb I've ever had on a car and it also produced the best overall mpg of any of the other brands but for all out brute performance, the Holley double pumper gets my vote. The 3310 is high on the list too but I never much cared for the other vac secondary Holleys that much with the spread bore being at the bottom of the list.
 
The TQ got a bad rap for the same reason and it was mostly a very simple problem like the secondary air door opening too soon and causing them to earn the name Thermo 'bog'. So far it's the TQ that has has earned it's place in being the best street carb I've ever had on a car
I could not agree more on that. But the TQ was just being introduced back in the day, so we had no prior experience with them. So, for the best all-around street/strip performance, everyone was happy with the 3310, it is a very versatile carb for a wide range of engine displacements.Depending on engine/combo, of course, we would use 750 & 850 DP's, and yes, even a dominator once or twice. Personally since then... my first choice would be a TQ as well. A few years ago, I had one on a Street Dominator manifold was an awesome combo.
 
I could not agree more on that. But the TQ was just being introduced back in the day, so we had no prior experience with them. So, for the best all-around street/strip performance, everyone was happy with the 3310, it is a very versatile carb for a wide range of engine displacements.Depending on engine/combo, of course, we would use 750 & 850 DP's, and yes, even a dominator once or twice. Personally since then... my first choice would be a TQ as well. A few years ago, I had one on a Street Dominator manifold was an awesome combo.
Even the dealership techs didn't know what to do with the TQ's when they showed up on the 1971 cars and were not adjusted very well from the factory.
 
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