Edelbrock issue or set up not right?

[Mark1972]

Now this engine was dyno'd with a Holley, although I don't know which unit. I've not had any issues with the Edelbrock I put on it, mind you as soon as the engine was in the car, I took it to a chassis dyno nearby and had them set up the new AVS2 800. He set it up and I've never had issues, but this year I've been a little harder on it being fully broken in. Now, when I floor it, it certainly goes, but after that, when I accelerate hard, it has a hesitation at first, for just a moment, and, it tends to stay at higher idle for a while. I have to kick it down a few times to get it back to under 1000 rpm. Obviously, Edelbrock make good stuff, so do I need to just get this thing to someone who's very familiar with them? Or is there something I can do myself to check something that might cause these issues?

 

[Bee1971]

Check FAST idle screw depending upon choke setting - Not your regular idle screw

Hesitation could bee as simple as an adjustment for secondary air door

What metering rod springs are you running ?

 

[GTX JOHN]

Make sure return springs are strong enough. Make sure throttle Blades are not
touching gasket or side of Throttle bores on Carb.

 

[Ironbuilt]

Tuning the AVS carb is simple. All you need is a timing light, a vacuum gauge and a tach.
https://www.edelbrock.com/pub/media/wysiwyg/documents/carb-owners-manual.pdf

 

[RJRENTON]

Now this engine was dyno'd with a Holley, although I don't know which unit. I've not had any issues with the Edelbrock I put on it, mind you as soon as the engine was in the car, I took it to a chassis dyno nearby and had them set up the new AVS2 800. He set it up and I've never had issues, but this year I've been a little harder on it being fully broken in. Now, when I floor it, it certainly goes, but after that, when I accelerate hard, it has a hesitation at first, for just a moment, and, it tends to stay at higher idle for a while. I have to kick it down a few times to get it back to under 1000 rpm. Obviously, Edelbrock make good stuff, so do I need to just get this thing to someone who's very familiar with them? Or is there something I can do myself to check something that might cause these issues?

When you had "them set up the new AVS-2 800", were these optimum settings recorded? These settings would have been: primary metering jets, primary metering rods, primary step up piston spring color, secondary metering jets, air valve spring preload turns, accelerator pump linkage settings, accelerator pump discharge nozzle opening, in addition to the float level setting, float drop setting and inlet needle size. Ignition settings would also have been recorded: innitial, plus rate (centrifugal) and vacuum. Plus choke pull off and fast idle RPM and fast idle cam clearances should hsve been checked and/or recorded. Knowing these settings, troubleshooting your existing issues will be so much easier to determine......perhaps beginning with the mechanical settings....fast idle cam drop RPM speed and choke pull off settings. Just my opinion of course.
BOB RENTON

 

[Mark1972]

Hey guys. Sorry, got called to work this morning and just got back to work on the car a few minutes ago. I'll gather the info I can and post it. I'll check the metering rod springs, and see what they used. Regarding the recorded settings, I asked for them last year when it was done, but he said his printer was down and asked if I could come back and get the print out at a later date. By the time I got back, they closed the doors for good, and I never got the specs. Also, regarding the Edelbrock manual for set up, that is exactly what I did when I first installed the carb. I had my timing light, tach set up, and vacuum gauge. It was after that I took it to be done by a professional who could read air/fuel ratios.

 

[Mark1972]

Currently, the metering rod springs are the orange, or 5Hg springs, which Edelbrock list as a "stock set up" spring. The metering rod is size 65-52, or .062"x.052", Edelbrock part number 1441. As far as the metering jets, the only ones missing in the kit are the .110" jets. At idle, 700rpm, it's pulling 12-13 inches of Hg. At 2000 rpm, it's pulling 18. At 3000rpm it's pulling 20. Excuse my ignorance, but doesn't vacuum usually drop as you increase rpm?

 

[Mark1972]

Check FAST idle screw depending upon choke setting - Not your regular idle screw

Hesitation could bee as simple as an adjustment for secondary air door

What metering rod springs are you running ?

Orange, which Edelbrock list as a stock set up spring.

 

[RJRENTON]

Currently, the metering rod springs are the orange, or 5Hg springs, which Edelbrock list as a "stock set up" spring. The metering rod is size 65-52, or .062"x.052", Edelbrock part number 1441. As far as the metering jets, the only ones missing in the kit are the .110" jets. At idle, 700rpm, it's pulling 12-13 inches of Hg. At 2000 rpm, it's pulling 18. At 3000rpm it's pulling 20. Excuse my ignorance, but doesn't vacuum usually drop as you increase rpm?

Since the engine is running without any appreciable load, your vacuum readings are typical. IF, you were on the highway, going up a hill, the vacuum readings would be significantly lower. Just my opinion of course....
BOB RENTON

 

[Mark1972]

I believe what the fella that was setting up the carb was shooting for was proper air/fuel ratio. He showed me on the screen that is started out at lower rpm(idle to 1800)around 12.9-13.4/1, then ended up closer to 12.5/1 as the rpm went up. He chassis dyno'd it to 6000, and he said he was happy with the af ratio throughout the rpm range. Like almost everyone else I dealt with, from the engine builder, to the place that dyno'd the engine, to the guy who set up my carb on the chassis dyno, they all were big fans of Holley's. I've not had anyone explain to me the obvious advantage of a Holley over the Eddie for a street cruiser. Guess it doesn't matter now.

 

[62 Dart Convertible]

Your high idle sounds like a sticky throttle cable aand/or not strong enough return spring.