AVS2 compared to Street Demon?

[fratzog lover]

(but I serious dislike the microscopic pump and choke link clips).

Tie a piece of waxcord or white string on them. If your eyes are old like mine! The drag magnet has saved me once or twice out in the stone driveway.

 

[Go Mango]

AVS2 I have needed about 3/8" spacer between the drop base aircleaner base and the carb. The fuel line inlet was hitting the aircleaner. No problem with the choke.

I had to add some bend to my fuel line because of the electric choke, but the factory 1970 340 air cleaner fit fine.

 

[gzig5]

Well I'm going to find out the hard way. Just put the order in for the 650 AVS2 and one of their thick thermal blocking gaskets. Going to be nice to finally have a carb that works right.

Mango,
Did you use AN fitting for the hard line at the carb or just a regular flare fitting? I don't think it should really make a difference? All the fitting they were suggesting online were AN but I don't think my flare tool is compatible with that. I'd like to have as little hose in the circuit as possible and I'm not paying big bucks for a pre-bent set.

 

[Go Mango]

Well I'm going to find out the hard way. Just put the order in for the 650 AVS2 and one of their thick thermal blocking gaskets. Going to be nice to finally have a carb that works right.

Mango,
Did you use AN fitting for the hard line at the carb or just a regular flare fitting? I don't think it should really make a difference? All the fitting they were suggesting online were AN but I don't think my flare tool is compatible with that. I'd like to have as little hose in the circuit as possible and I'm not paying big bucks for a pre-bent set.

I unscrewed the fitting that the fuel line goes to from my original Carter avs, and used it on the avs2. Edelbrock recommends a banjo fitting that might work better, but I didn't need it. I did have to use the thick gasket, but I don't remember what issue caused me to need it. They also recommend a throttle linkage kit for mopars, but I didn't need it either. The only thing extra that I bought was the thick edelbrock gasket.

 

[Go Mango]

My installation was really easy. I've got a 4 speed, so there was no extra linkage for a kick down, and my factory carb was also an AVS. I suppose some installs could be more difficult, but I don't think it should be too big of a deal.

 

[512Stroker]

Well I'm going to find out the hard way. Just put the order in for the 650 AVS2 and one of their thick thermal blocking gaskets. Going to be nice to finally have a carb that works right.

Mango,
Did you use AN fitting for the hard line at the carb or just a regular flare fitting? I don't think it should really make a difference? All the fitting they were suggesting online were AN but I don't think my flare tool is compatible with that. I'd like to have as little hose in the circuit as possible and I'm not paying big bucks for a pre-bent set.

Edelbrock has a drop base air cleaner that works great with the AVS carbs.
I have one on my 340 auto trans setup on an Edelbrock intake.
I used a thermal carb spacer and banjo fuel line fitting everything has good clearance and performs well.

 

[68 Coronet RT]

My 650 AVS-2 showed up today. Found it on e bay for $310 free shipping no tax. Got it installed and I set the choke and fired it up. What a difference from the 750 performer I took off. I set the idle mixture screws and she runs just a smooth as can be and it doesn't burn my eyes in the garage and the choke is dead on it worked perfect. Looking forward to getting it out on the road but with 3 feet of snow in my yard and a prediction of a lot more coming this week it's going to be awhile but the first day of spring is only 18 days away.

 

[7milesout]

Yeah - My AVS is still sitting on the shelf in front of the Scamp. I was going to do the season opener test and tune weekend on 3/1 to try to hit my 13.999 E.T. goal. But a coolant leak put an end to it. The radiator is fixed and will go back in sometime this week. I also have voltage issue to sort out.


7milesout

 

[gzig5]

Those of you using the AVS2 with an automatic transmission, can you post a good pic of the throttle and kick-down linkage? I figure I need to remove some of the stuff from the Holley and move it to the AVS2 but is it just the stud, or that bracket as well?

 

[Go Mango]

Those of you using the AVS2 with an automatic transmission, can you post a good pic of the throttle and kick-down linkage? I figure I need to remove some of the stuff from the Holley and move it to the AVS2 but is it just the stud, or that bracket as well?

I'd be interested in knowing this as well. I've been recommending this carb to anyone who will listen, but I've no idea about the kick-down linkage.

 

[7milesout]

gzig5 - I believe the AVS2 kickdown linkage will carry over from the performer and AVS carburetor. I can show a couple pictures of that, if you think you'd care to see it.

My car is making me sick at the moment. It has wiring issues, and also vapor locks at the drag strip because the fuel line is so close to the headers. I'm combatting these issues. I am resisting putting my AVS2 on the car until I can hit 13.99 at the strip on the current set-up.


7milesout

 

[gzig5]

gzig5 - I believe the AVS2 kickdown linkage will carry over from the performer and AVS carburetor. I can show a couple pictures of that, if you think you'd care to see it.

7milesout

Yes please.

 

[68 Coronet RT]

Here's a few pictures, the bracket that I had on the 750 performer mounted to the 650 AVS2 with no issues. I also used a Banjo fuel line to clean things up a little. I'm also using a half inch composite carb spacer so the linkage is on a little angle but it works perfect.

 

[Darter6]

Not the best photo but may help.68 Valiant Edelbrock linkage adapter,kickdown.Not factory looking but worked for me.

 

[gzig5]

Looks like something is bolted onto the stock linkage. Is this it?
Edelbrock Throttle Lever Adapters for Performer Carburetors 1481

 

[68 Coronet RT]

Looks like something is bolted onto the stock linkage. Is this it?
Edelbrock Throttle Lever Adapters for Performer Carburetors 1481

Yes that's the same adapter I bought.

 

[MopaR&D]

I like the Street Demon, comments about Demon carbs being junk aren't related to this carb at all. Demon (Barry Grant) had quality control and final manufacturing issues (lots of carbs sent with shavings inside, incomplete machining etc.), I believe they came out with the SD design right before Barry Grant got bought out by Holley, which is why it's now called a HOLLEY Street Demon so you know it'll work and be made right.

Personally the AVS2 seems like a waste for that much money; you could get a used Carter or Edelbrock AVS for 150 bucks and just swap over the boosters, big deal. The Street Demon is a completely new clean-sheet design, first new 4-barrel in what 40 years? The newest one I can think of is the ThermoQuad which you can tell heavily influenced the SD design.

Doesn't mean the AVS2 is bad I just wouldn't spend the money on a new one if it's really just an AVS with annular boosters added. Still running on a 60-year-old carb design plus you can't get the "aircraft-grade composite" fuel bowl to keep the gas cooler. JMHO

Oh yeah I'm running the 750 cfm Street Demon on my Duster's 5.9 Mag 'hybrid' it works awesome. I have also tuned and run Carters and Edelbrocks they are fine carbs just a tad old-school but I HATE the bowl design, can't go around corners or hit the brakes too hard you might stall out!

 

[68 Coronet RT]

I have also tuned and run Carters and Edelbrocks they are fine carbs just a tad old-school but I HATE the bowl design, can't go around corners or hit the brakes too hard you might stall out!

That's funny I have never had that issue with a Edelbrock but I have had more issues with the holley that I had on my 68 Coronet RT. Never could get it to run right one day perfect next day run like crap. Installed the 800 thunder series all issues went away. There are a couple of guys in our car club that run the street demon and they run ok but a lot more money than the Edelbrocks

 

[12many]

There are a couple of guys in our car club that run the street demon and they run ok but a lot more money than the Edelbrocks

Not sure what pricing youre looking at, but a 750 Street Demon is about $350+/- depending on where you source it, they are not "a lot more money" than any Edelbrock from what I've seen. The Demon is just about the cheapest out there.

 

[68 Coronet RT]

I paid $310.00 free shipping no tax

 

[MopaR&D]

I have also tuned and run Carters and Edelbrocks they are fine carbs just a tad old-school but I HATE the bowl design, can't go around corners or hit the brakes too hard you might stall out!

That's funny I have never had that issue with a Edelbrock but I have had more issues with the holley that I had on my 68 Coronet RT. Never could get it to run right one day perfect next day run like crap. Installed the 800 thunder series all issues went away. There are a couple of guys in our car club that run the street demon and they run ok but a lot more money than the Edelbrocks

You can get Street Demons at most parts stores now alongside the AVS-2 for ~$350. They all work well, I actually like Holleys too. Maybe the newer Edelbrock Thunder carbs are different but I had an older Carter AFB 625 cfm and it worked amazing to be honest, great carb for the street but it liked to boil modern ethanol-gas in hot weather and would spill over a bit from the boosters in hard cornering. It didn't have quite enough airflow for a built 360 so I sold it and got the 750 Street Demon. I think carbs are more prone to have issues due to age or bad build quality vs. design. You might have gotten similar results with a brand new Holley Street Avenger, not saying it's better just that all brand-new carbs tend to run perfectly once tuned unless it's junk from the factory.

 

[7milesout]

Guys,

I'm a newbie here to this scene and carbs. So I appreciate anyone evening listening to a word I say. I have no experience with Holley. The reason I'm messing with the Edelbrock is because it is what came on the car. But I've fell in love with them due to the ease of working on them. That and the fact that one day at work when I had a bit of free time I decided to make a spreadsheet that would help me with the tuning. I put a whole new exhaust, including TTi headers on my LA 360 when I took ownership. And a brand new 1405 (600 CFM manual choke). The spreadsheet plus the AFR gauge, my car is tuned to as good as it's going to get. And it runs really good. Good power, and nice response at light throttle.

I have only one problem with the carb. And it's the same as most others experience. About 1 second after throttling away at light throttle from a stop, it experiences a lean spot. For about another second. I've had the pump at all 3 settings. Nothing stops this. But it is not horrible. Just slightly annoying.

Other than that the carb is great. None of the other issues mentioned about sharp turns or hard stops. Course I try not to do either with a 72 Plymouth Scamp.

 

[68 Coronet RT]

Check your timing, initial should be around 12 to 14 and total should be 35 to 36 degress. I thought I had a lean spot also but it turned out to be my timing

 

[7milesout]

The AFR gauge paints the picture perfectly clear. It's a lean spot.

 

[68 Coronet RT]

The AFR gauge paints the picture perfectly clear. It's a lean spot.

You have a few options. In your owners manual look under your carb number ( 1405 ) Calibration Reference Chart. You are going to want to go richer, start with 4% that's a rod change only. If that doesn't cure it you will have to do a rod and jet change.