What is the vehicle? What does it weigh, what rear end gears? What trans? Where do you live, what is the ambient temp while you are driving?

If engine temp is too cool it will bog, unless tuned to run at that cool temp. Is the heat crossover in the intake clear and not blocked by a gasket? If you have not even checked the outboard springs yet you are missing important info. Know the basics first, then get fancy.

Why not offset linkage? THINK about it, WHAT does that linkage do? It closes two end carbs, so when your foot says to close them, it needs to happen right now. The linkage does not open the carbs.

WHY do you want offset linkage, what is the gain?

1970 Challenger 340 6 BBL 3.55 gears whatever a stock one weighs probably between 3000 and 3500 lbs TX torqueflite between 50 and 70 degrees I don't know on the crossover and haven't checked the outboard springs.

Why would I want to offset the linkage? I was curious about it and the pros and cons of it since I read that taking one turn out of the rear carb linkage and adding one turn into the front carb linkage may be a possible solution to bog/off idle hesitation in a Jan 92 Chrysler Power article on tuning 6 packs and that's what I'm trying to tackle.

From the text...

Make sure the timing is 15 - 18 deg btdc [advance] at idle. THIS IS IMPORTANT

Carry on.

Anyone have any tips on how to modify the slot to limit total timing? Where is the slot that I need to modify?

I have initial at 10 right now because there is 24-26 mechanical and if I go over 10 I would have too much total timing.

To rule out the accelerator pump should I disconnect the linkages and vacuum to the outboards and see if it bogs on just the center?

(1) the FBO plate ($25 to your door) is the fastest/easiest. You can weld the slots up then file em down to the right amt which is time consuming but free (exc for the welding) and the FBO plate has slots for 10-12-14-16-18 (not mine but I eyeballed one) & for dead on dist tuning if the vac gauge method for initial then wants an odd # to get to say 35 total (tried & true SB amt)then the plate will be slightly off (OCD anyone). Jimmy G the JB weldmaster uses that instead of welding. What I would suggest NOW is bump the initial up to 18/slow the idle/reset initial to 18 (if it changed) & see if you can get a good/low(er) idle. it'll take 5 minutes and you can set the initial back in no time if you ain't happy with the results. EDIT the slots are the 2 oblong holes in the flat cam plate in the dist (pop the cap & you can see em & each one has a pin in it & you are limiting how far that pin(s) can move in the slot by shortening the slot on each side)

Here's some pics of the springs in the pods. Not sure if I need different springs for the bog issue. They look pretty light but don't have a color like black, white or yellow. Anyone know?

I just saw a chart on here for them (color VS strength) I'd sure think that one would be the "plain" one, iirc the lightest which would as you know come in the quickest/be the most likely to bog

Anyone have any black or brown springs from a kit that they don't need? Just thought I would ask before I buy a spring kit. Also what part number kit would I need should I not score some on here?

I can get Edelbrock springs for the secondaries locally. Part #12412

http://www.oreillyauto.com/site/c/detail...3&ppt=C0359

Do they have to be Holley springs?

Holley PN 20-13 you'll need to order 2 kits, total approx $30 use genuine Holley parts, you don't need any further issues

Generally I start with the white springs, and move up the spring range to tailor the opening rate/rpm of the secondaries, rather than working downward from Brown or Black springs...I prefer the secondaries coming in as earliest as possible, and basically as demanded by my right foot, rather than "waiting" for the system to overcome high spring tension in the secondaries

Mike

I've read that the Edelbrock and Holley kits are the same. Can anyone confirm?

If you want only springs you can get a pair of any color from Ouick Fuel for $10.00 + shipping !!

Did some more research on this. Holley makes the Edelbrock kit. They are all the same. BIG-10258, 20-13, B5006K, Edelbrock 12412.....and probably some others.

Buy two sets of springs. You will need one for each carb. Additionally, you should buy two new vacuum diaphragms as they are often damaged due to frequent installation and removal of springs. I was told a long time ago to adjust the springs so that you don't have a noticeable "zoo-whaaaaa" when kicking in the secondaries in high gear at 45-55mph. If there is a noticeable bog, and then a pickup, the springs are too soft. All my experience is with a modified RB and six pack set up. I run brown or purple springs in my outboard carbs. If you are getting too big of a hit of fuel off the line, and that is leading to your bog, you can adjust the amount of accelerator pump hit by adjusting the nut on the lever that actuates the pump. Loosen the nut to eliminate some of the hit at launch.

Most of what I read says 15-18 initial, but then I've read some other info that says not to go that high and keep it around 12 with my cam so I'm not sure what is best.

The engine is a 340 with 10.5:1 compression and the cam has 114 centerline. I'll be running 93 octane pump gas, Autolite 65 spark plugs and have brown springs in the vacuum diaphragms. Should I still go for the initial of 16? I have a limiter plate that will allow me to limit it to initial plus up to 18 more degrees.

I'm (was) running 18 on a bone stock 83 318. you might do the "vac gauge method" & see what that gets you for what it wants for initial. No way would I think 12 would be better than 16 even WO a cam & with it even more reason to bump it up. At least see what the VGM comes up with & try both ways if desired & tune for both (idle speed back to your lowest reasonable hot idle speed along with mixture screws) & see which acts the best then change the slot choice in the plate then springs then adj the can.