Edelbrock AVS question....today only

66furys said:
Another learning moment for me.....the secondaries dont open on the stock manifold. Both mfr and sales outlet said all good for the AFB replace.....hmmm. I have ordered an adapter riser plate to allow more room for larger throttles. Edelbrock has notes about this for ford, chevy and for mopar thermoquad....but not the AFB. Same bolt pattern, but 383 stock manifold holes too small. Do more homework than I did.
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I used a Felpro 60123 to keep the AVS2 800cfm from hitting my stock manifold.
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Very nice resto work. I like the gasket, and am curious whether what look like brass spacers affect compression....interesting.
 
saforwardlook said:
I believe the original AVS carburetors on our cars were 650 CFM. This carburetor you purchased is 800 CFM so that is probably why the secondary throttle blades do not fit.

With the new annular primaries the new AVS II carburetors deliver much better fuel atomization than the original design that leads to much improved throttle response, especially off the line but also part throttle. The original AVS carburetors were very marginal in this performance area and if you didn't have your crossover fully hot, fuel vaporization was really bad with the original AVS design leading to crappy throttle response during warm up until fully warm.
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THANK YOU FOR THIS SUCCINCT OBSERVATION ABOUT THEIR 1ST GENERATION AVS CARBS!! I got a Performer 1405 w Gertrude last year, and had it rebuilt and put it on a stock iron 4 bbl intake. Sure as ****, until Gertrude warms up to 195 F +, she coughs, spits and pukes in mid throttle, which is where we need her to be at her Beast in morning crush hour traffic. I suppose I should at least put a 195F thermostat in for the cool season, if I want to save pennies on warm-up time. Was mulling over whether to get their rods and jets kit for this unit. I like how well they document the procedures for various adjustments. As of today, the carb is set for the NIB factory rods and jets.
 
66furys said:
Very nice resto work. I like the gasket, and am curious whether what look like brass spacers affect compression....interesting.
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I suspect they used soft malleable metal to control compression such that the gasket/spacer is not distorted.
 
Hmmm, malleable.....I think of my youth. I was reviewing some changes to a submarine shaft made of an exotic. There was a hard notch, that I pointed out, and one of the shipyard engineers asked me if I had heard of a high modulus of elasticity......hmmm, another day, another lesson. Malleable.
 
I am a believer in adjusting the choke during its early ops. Some are slow, some are fast, but they need to be adjusted when this happens in the warmup. The early ones had a tube that warmed the springs. Unfortunately the mid term ones, as on my 383 have a spring in the manifold that is marginally adjustable. And, the electrics can be adjusted a bit. But, for early problems, it has been my experience that it is fuel before the carb warms. The later fuel injection units had a separate injector that added fuel when cold to compensate. Once the beast is warm and can vaporize the fuel all is well. But not so for cold ops. Dont mess with secondary stuff for cold ops.
 
70bigblockdodge said:
Put more timing in it. If your at 35° total you need it to come in earlier.
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Changed distributors. This one has a less aggressive vac advance which plays nice w the Edelbrock. Come to think of it, she hasn't complained much since installing this one, I use a manual choke of course, which is why I LIKE the 1405. I need to do a total timing data set again with this distributor, and again, after I put the FBO retard plate on one of my 2444676s after a little refurbishing. I'll got for minimal mech advance with the aggressive vac advance, to avoid shooting over 36 degrees total. I had to disconnect that damn thing and just use mech advance, which did very nicely, once warmed up well, as mentioned.

Once I'm really happy with the ignition, then and only then will I experiment with the metering rods and jets. For now, she develops plenty easy power, smooth as silk, and I like that, but a shorter warm-up would be good.

Also need to replace the spring on the crossover butterfly in that passenger side exhaust manifold too, and likely the entire spring set. I'm glad I have something in this one, having removed the other entirely for the summer.
 
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66furys said:
I am a believer in adjusting the choke during its early ops. Some are slow, some are fast, but they need to be adjusted when this happens in the warmup. The early ones had a tube that warmed the springs. Unfortunately the mid term ones, as on my 383 have a spring in the manifold that is marginally adjustable. And, the electrics can be adjusted a bit. But, for early problems, it has been my experience that it is fuel before the carb warms. The later fuel injection units had a separate injector that added fuel when cold to compensate. Once the beast is warm and can vaporize the fuel all is well. But not so for cold ops. Dont mess with secondary stuff for cold ops.
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WISE words! I <3 my manual chokes.
 
When I was a squirt, I got a used distributor machine, and re curved a lot of distributors for folks during the car years of the 60's. I still have, after all these years, spring sets that have not been opened, and some weights. Used to know what I was doing before getting to the golden years and losing faculties. Cant recall how many carbs were rebuilt along the way as well back then. We used to have a great carb cleaner. Went to auto parts and got Gunk recently. That crap would not even turn brown when soaking....and took NOTHING off the carb. I later read that maybe using pine sol to soak could work. Next time. One more fine point on the vac advance is the type that is used, some like full and some like timed vacuum, and never the twain should meet. Basically, at higher speeds you wont have enough manifold vac for advance.....might be a bit, but you need a machine to apply vac to the unit and measure advance while spinning and grinning...you can do all of that easily on a machine. Then compare with engine vacuum at speed and load to get a feel for where you're at. Mo fun
 
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