What Carb for Poly Stroker

66 Sat said
Hey guys I'm looking for some input on my next carburetor. It's a 66 Satellite with a 354 poly stroker. 3.58" Scat forged crank, Scat rods, Ross pistons 0.065 over, 10.8:1 compression. Poly heads with a little bit of porting, 1.94"/1.60" valves, Schneider solid lifter cam 264F (220° at .050, 0.450 lift). Topped off with a factory cast iron intake and currently a 1850 Holley 600 (vac sec). It's got headers, stepped from 1 5/8 to 1 3/4, 2.5" dual system.
Car is auto, 3.23 rear, used for hot street, cruising and at the track say 6 times a year. Weighs 3,640 lbs.
The car runs great with the Holley but I'd like to try something else. I've also got a 700 double pumper that I swap in and out and the car feels faster with the bigger carb (and made 7hp more on the chassis dyno, 341hp at the wheels vs 334hp with the 600) but the 600 is better on the street. I'm going to try the double pumper at the track early next year to see what difference it makes there.
There's so many choices my head's spinning.
I wouldn't mind trying an Edelbrock AVS2 but should I go 650 or 800? Normally I would think 650 but with the annular boosters would the 800 still work ok?
Or maybe a Holley 670 Street Avenger v/s?
Or a 650 double pumper?
Or a Brawler 680 v/s BR-67317?

I was leaning toward a 625 Street Demon but the reputation for poor build quality and a few design issues is putting me off.

Then there's boosters: straight, downleg, stepped, annular...man there's some choices out there.

I'm wondering what I'm leaving on the table with the 600 1850. I'd like the same reliability (super reliable), better low end and midrange, and maybe some more at the top (so basically more everywhere haha).

Any advice appreciated - I realise this is a very open question and one where brand loyalties are strong.

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The engine now has 354 inches I take it. Now the original carbs on the 315 or 318 would have been a Carter 2 barrel or possibly a WCFB or an early AFB.
Your main use intention is street driving, so IMHO you would be best served using an Edelbrock AVS2 650 carb. On the street you will see better response and fuel economy. Now that will mess in Rusty's Corn Flakes, and I have no interest in if that occurs clockwise or counter clockwise, as I do not intend to offend. A double pumper Holley was designed and intended for race use. The double pump shot helps response on an engine with a lot of cam and carb get through the stumble on mashing the throttle to the floor.
Yes the Holley 750 or the AVS2 800 are most likely to give better times at the strip, but economy will tend to suffer. The AVS2 not as much as the Holley. Yes I know you can tune for mileage, but the reason for the big carb is track time.
Racers use the Holley because it is quick to change tune at the track. Between 750 CFM carbs between Rochester, Carter/Edelbrock or Holley, the Holley may flow slightly more air.
For Holley carbs tuning you get the Strip Kit with a selection of jets and air bleeds to tune for atmospheric conditions at the track.
Rochesters have been more difficult to get jets and metering rods for as they were more intended for OEM use, and tuned for that application. Since the introduction of the Edelbrock Quadrajet series, they have calibration kits for them.
The Carter/Edelbrock AFB and AVS carbs have calibration kits available. One nice advantage with these is that the tune can frequently be adjusted with primary metering rods which can be changed without removing the carb cover. Just remove the air filter housing and the metering rod and piston covers with one screw in each. No fuel spilled.
The 800 AVS2 can be tuned easily to give street and race performance, but I would urge caution about over carbing a street driven engine. Again, on the race track is one thing but how much power do you really give up.driving on the street.
As enthusiasts we need to be responsible. Our hobby is under attack and we do not need to toss nitro on that fire. Doing burnouts, fishtailing and drifting with lieberloon wokie tokies watching on the sidewalk, is not a service to any of us. To the police and law makers they see no difference between any of us. Similar was the impression of motorcyclists. Some thought if you were riding a motorcycle your mindset had to be to come and rape their daughter or wife, so they would try to run you off the road.
I would chose a bit less power at the track as you give up basically nothing on the street.
Considering that a carb is a quick and simple component to change, you could run the 650 on the street and swap on the 750 or 800 for track days. Run what you have already in the shop.
At this time it is not wise to spend money unless you have to. I hold minimal faith for a positive direction of the world over the next 5 years to 10 years.