Josh R

iTrader: (1)

Ok so i have an LG4 with a full exhuast. I made it so i can adjust how far the AV over the secondaries opens. I also bought a set of CC rods, CK rods, and a G hanger. I first went all out and put the G hanger and CC rods in and made the AV open fully and also have no tension. I took it for a ride and let it warm up. It bogged around 3 thousand but once it cleared up it flew. I then tried the CK rods with the AV stock open. It bogged even more. At low Rpms when i would hit the gas the engine would lose all power. When I let off a tiny bit the engine would jolt with power. I think that thats a lean bog. I really have no idea whats wrong. I then tried tuning the AV to open less than stock. It still bogged. I put the CC's back in and the AV really closed and it would bog and then go fast and seem way to rich at high RPMs. Which makes sence. No matter what i tried the car would bog when i floored it. I have it timed advanved right now. It ran good with stock rods and hanger. What could the problem be. I've read stuff and it seems like when i floor it its getting too much air. Which means i need a hanger that will give it more gas once the AV opens. Does this sound good? I really don't know.


Ok i know no one has posted yet but i realized something else. I put the CC rods in with the G hanger and retimed it a bit. The timing mark is at the beginning of the timing mark indicator thinger. When the car first starts (not cold) it runs perfect. When i started it again it was at like 180 degrees. Then after a few minutes of driving it gets all boggy again. What is changing in the engine that after begining driven a little it gets boggy?

Fast355

iTrader: (2)

The A/V is tricky to setup. You need to adjust it to zero tension. You do this by tightening the screw until the open butterflys just snap closed. Once they do, tighten the screw 1 full turn, the tighten up the jamb screw.

JamesC

iTrader: (5)

Sounds as if the AV tension isn't correct (IIRC, bog requires more tension). If you haven't already, you might consult the tech article.

https://www.thirdgen.org/quadrajet

By the way, I played with rods/hangers along with an L69 dual snorkel set-up (to include the ducts and hoses) and full L69 exhaust. Made me smile!

JamesC

Josh R

iTrader: (1)

Yeah you guys are right about the AV tension. It was too loose. It said in the tech article that the vacuum would let it out slow enough, but apartently not. Now my new problem is that i f**ked up the AV spring. No matter which way i turn it, it doesn't keep the flaps closed. I tied a rubberband from the AV lever to the screw i put in place of the tab and took it for a ride and it had no bogging. The rubber band was too tight though because the secondaries weren't opening until near 4500 rpms. Is it hard to fix that spring? Or is there a way to make the vacuum let it open slower???

Josh R

iTrader: (1)

help?

five7kid

iTrader: (14)

When the engine is cold, the choke locks out the secondary throttle blades.

Do you have the choke pull-off on the carb and working properly? It should have a link to the AV. It is the first line of bog defense, and shouldn't be defeated. If it leaks (doesn't hold when pulled with a vacuum pump like a MityVac), you will bog more readily.

I've never had to replace the AV tension spring, but it involves removing the AV shaft, which means the AV butterfly pieces have to be removed from the shaft. They are held on by staked screws, which have to be carefully ground off and new screws (most likely) used and re-staked. A bit of a pain, but do-able.

A while back, someone posted about using an old accelerator pump spring (I believe it was) over the air cleaner stud with a nut/washer to provide the AV spring load. Not saying I recommend it, but that would be one alternative to tearing the AV apart to replace the stock spiral AV tension spring.

jamon8

iTrader: (3)

sometimes the plastic cam that raises the rods wears out

check it out