mixture screws

I've got an 82 XJ 550 maxim. I pulled the plugs to the mixture screws and was curious as to their setting. Now I'm wandering what the factory setting is supposed to be. On my spare set from left to right it was 1 1/2, 2 1/4, 2 1/2, and 3 1/2. On my running set they were 4 1/4, 2, 3, and 2 1/2. I kinda thought they would be set the same as the brass plugs were still in and never looked to be tampered with. Any thoughts are welcome.

 

Replacement plugs are available, so it's possible they're not virgins.

On the other hand, if they could manufacture them with consistency they wouldn't need adjustment screws at all.

 

didn't realize they actually made replacement plugs. They looked origional-ish Any how i was just curious, i'll put them at stock if i can find the info and adjust from there.

 

The mixture screws can be adjusted to tune your engine. Get a color tune plug and adjust to get a nice color. You should be set. I just plugged mine with silicone. If I need to adjust all I need to do is dig the silicone out. Check with Rick Co Matic about tweaking those adjustments

 

It's very common for the factory settings to be widely varied.
Once you've moved them as MN said you will need to colortune and or do plugchops to get it right again.

 

I should have elaborated more on what I said:

There is not a "standard" or "stock" mixture setting. Each carburetor will be different. When I open a rack that I believe to have the OEM settings, I put each carb back to it's original setting for my starting point. Colortune from there.

 

If the plugs were still in place those probably were the original settings. yes new plugs were available but I've never seen anybody actually install them. As Carl said, the original settings could be all over the map (and be correct.) I believe the FACTORY used an EGA to set them (hence the little plugs on the bottom of your exhaust pipes.)

 

So just put the screws back to where they were and tune from there. Sounds good.