Hi guys, I just seen that someone down the line decided to mess with the outboard idle mixture screws and broke them. I managed to scrounge up a good base plate and fixed one till I seen that the rear carbs base plate had the same issue and unfortunately it has the same problem as the front...

I was wondering if anyone had any insight as to how to extract these mixture screws, or where I can send it for a quality fix...

Thanks!

See if you can find a machine shop with an EDM (Electrical discharge machining). Just had a broken tap removed from a Holley carb using an EDM, cost me $30.

Thanks for the tip! Hopefully I find someone near my area that can do it.. Most of the machine shops here in SoCal are premadonna's ... If it isn't a 10,000 dollar job they don't want to "tool up" to mess with it...

http://pages.ebay.com/link/?nav=item.view&alt=web&id=261931901538&globalID=EBAY-US

If you get them out clean consider this Idle Screw kit. A little pricey up front but it'll save serious time when it comes to tuning.

I bought that kit and it works great, so easy to get at the rear screws.

The way we used to adjust the idle was to get as smooth an idle using the front carb adjusters, the switch carbs and do the same, works almost as good....

Joe

PS then put carbs back in original positions if you have staggered jetting, (recommended)

I seen that screw set on Ebay.... Although pricey, I can justify the expense for the ease of access....

Whoever at holley designed the base plates on these carbs should be, well i wont go there..... Putting brass idle mixture screws that bust with the slightest bit of pressure doesn't make sense to me, nor does the location..... oh well, I guess it could be worse, non adjustable like a Chevy!

I agree, the screws and adjusting tool are a must for six packs. My TA idles fantastic once they were installed.

Its funny you say that.... I have never had any experience with six pack set ups prior to my challenger.. i didnt think that much of the idle circuit is actually ran off the outboards... Boy was I wrong... I was messing with the center carb all day trying to get the stumble out... as soon as I was able to play with the front carb, I noticed a night and day difference! I'm excited to tinker with it a bit more and get it where it needs to be....

Tinker like this,once you have no change in idle with or without air bleed covered you're where you are supposed to be. .

Thanks again Bill!.... Cant wait to try out these tricks once i get the broken screw worked out....

What makes them so easy to break also makes them so easy to get out, brass. A small small bit on a dermal will get most the center out and the rest will come out with the point of a 16 penny nail gun nail.

I had one in both the front and back give me grief many years ago.

Just ordered up. eBay listing said "last one". Perhaps eminent doom marketing
ploy, if so worked for me. Besides I did prefer not swapping out throttle plate(s) if not forced to. I believe now you must also change out throttle butterflies to new plate(s). Am I misremembering that at one time this was not required?

Fuhgeddaboudit that seller will get more made up. He's got a little gold mine with that product. Maybe $2 worth of hardware and tool. Nice profit margin.
Don't get me wrong, I'm glad I have it. I easily drop $60 buying beer every time I go to a ballgame with nothing to show for it but worn shoes from trips to the men's room.
Glad to see the American Dream come to life! At least for one ingenious dude!

There was a problem with some of the early plates sticking,they were stamped #199,plate stamped #226 corrected the problem,no need to change.

I put my baseplates in a vise (wrapped in a shop rag), put a propane torch to the screw thread area & just dug at the brass screw with a little screwdriver and a pocket knife to "cut" a slot into it and the screws turned out easy once heated. It's a crude method, but it worked for me. Then all you need is replacement idle screws from Holley.

FYI- I have the adjuster tool/hex head idle screws and I don't see it as that big of an advantage since you still need a Promax base plate to get to the back carburetor. The screws are much less likely to strip out again though.

I just read through his write up here: http://www.ebay.com/itm/261931901538 and he doesn't mention having to switch to a Promax baseplate so that his tool/idle screws work. Are we talking about the same tool/idle screws? I would like the ability to adjust the outboards w/o dismounting.

This tool / screw kit works fine for the rear carb screws. You have to figure out exactly the route through the choke linkage, fuel line, vacuum lines, it fits and works both sides. Read thoroughly the instructions on the eBay page.
No need to get a ProMax setup. And you can use the stock screws for the front carb-

Edit- I'll be installing the tool before starting the engine. You can feel the ball end of the tool clip into the socket head idle screws.

Thanks for the clarification.

Looks like I was wrong. That is the kit I got and looking at it (no flex in the tool) I figured "No Way" is that going to access the rear carb with straight screws, so I bought a Promax rear plate which is still a tight angle to get at and I'm using the stock screws in the Promax plate. From the your pictures it looks like I wasted my money on the Promax rear plate.

We all make mistakes sometimes. It just sucks when good money goes after bad. You can always sell the screw kit.