SlinktRR
Well-Known Member
I have run an Edelbrock AVS 800 (1812) for a few years now on an RB 499ci stroker. It dyno'd at 600bhp and 625 ft-lbs torque and runs really well with a ported holley street dominator and trick flow 240's, 18 initial 34 total timing. Cam is Comp XS290 solid, so 10" vacuum most of the time. My wife keeps complaining about the fuel smell. The AVS I have tends to run lean at idle, so I've been adjusting here and there to clear that up. Full throttle, idle performance, in gear it runs great just the lean stink. I bought the 800 for super cheap used years ago so I figured hey I'll buy the new AVS2 800 from summit, it should just bolt on and go.
I put it on and tried to set idle. It idled beautifully, 10" vacuum on the gauge at 1000 rpm. The old 1812 came stock with .113 jets, but I changed those to .104 when I first got it and tuned to 7052 metering rods which is how the 499 engine liked it. The new 1912 AVS2 comes with .104 main jets but stock calibration has 6552 rods and orange 5" springs. So I ran it like that and it idled smooth. Idle screws 2 turns out, like the old carb.
Then I put it into gear and it would die. Checked plugs, lean. I had to go 5 turns out on idle screws until it would idle in gear, which I have never had to do on an AVS. Also put in yellow 4" springs. Still rough in gear but wouldnt die. Around town it ran terrible so I used the edelbrock chart and started changing rods. Any change and the idle would go bad in gear. I had to do other things at home so I set back to stock drove back and parked it.
I'm going to go through the old AVS and clean it up, recondition it to put back on if I need to. In the meantime I'm going to call Edelbrock to see what ideas they have and also ask FBBO for some help. To sum up, only change was AVS to AVS2. Jet change? I may need to deviate a lot from the edelbrock tuning guide for jetting. The good news is the lean stink is gone, but it runs like *** so not a good trade off. The 5 turns out idle screws also threw me for a loop which makes me think there is something wrong in the idle circuit of the new carb.
I put it on and tried to set idle. It idled beautifully, 10" vacuum on the gauge at 1000 rpm. The old 1812 came stock with .113 jets, but I changed those to .104 when I first got it and tuned to 7052 metering rods which is how the 499 engine liked it. The new 1912 AVS2 comes with .104 main jets but stock calibration has 6552 rods and orange 5" springs. So I ran it like that and it idled smooth. Idle screws 2 turns out, like the old carb.
Then I put it into gear and it would die. Checked plugs, lean. I had to go 5 turns out on idle screws until it would idle in gear, which I have never had to do on an AVS. Also put in yellow 4" springs. Still rough in gear but wouldnt die. Around town it ran terrible so I used the edelbrock chart and started changing rods. Any change and the idle would go bad in gear. I had to do other things at home so I set back to stock drove back and parked it.
I'm going to go through the old AVS and clean it up, recondition it to put back on if I need to. In the meantime I'm going to call Edelbrock to see what ideas they have and also ask FBBO for some help. To sum up, only change was AVS to AVS2. Jet change? I may need to deviate a lot from the edelbrock tuning guide for jetting. The good news is the lean stink is gone, but it runs like *** so not a good trade off. The 5 turns out idle screws also threw me for a loop which makes me think there is something wrong in the idle circuit of the new carb.