I'm wondering if anyone can help guide me in the right direction on how to install different carb jets? I know basics about tuning but I have not yet had to change out jets.

I just purchased a 750 mighty Demon carb and it seems to be running a little rich on my setup. To correct this I would like to decrease the jet size and see if that will take care of the problem.

If anyone can help me out I would really appreciate it. Or if anyone knows of a website where they have pictures of the process that would also be very helpful.

Thanks

 

Welcome aboard TGO!

You have to remove the fuel bowls. Each bowl is held on by 4 bolts (take the fuel line off first, of course). The jets are in the metering block behind the bowl.

Steps of 2 jet numbers at a time (for instance, from 76 to 74) are recommended.

 

Thanks!

Are there any tricks to taking the fuel bowls off and putting them back together or is it really straight forward?

Thanks for the help

 

Pretty striaght forward. Just unhook the fuel line and rmove the 4 bolts (total of 8, 4 for each bowl) and then change the jets. Simple.

 

When you remove the first bottom bolt from the bowl, that bowl will drain. Good idea to have something under it to catch the fuel. You can get a fancy little cup that has a chute on it to go under the bolt, or you can cut a tin can short enough to fit under it. Whatever turns your crank.

 

I also need to jet my Holley 750 cfm vacc secondary carb. How do I know what jets to start with and when to stop?

 

http://www.holley.com/data/TechServi...ech%20Info.pdf

 

Thanks again for the info.

I'm going to try changing them out tonight!

 

Your mixture is about perfect when your plugs are a tanish/browinsh/goldish color. If their black, lean it out, if they're white richen it up (or you could have a bad head gasket).

 

Five7, thanks for the site, I will check it out. The car backfires badly when I get on it and the left off. I have been told by several people it needs to be jetted? If I recall correctly when I pulled the plugs they were blackened = too much fuel . The motor was in a truck and I'm in the process of putting it in my Camaro. We'll have to see what happens. Thanks again. Later
-Greg

 

Just wanted to say I got the new jets in, went down two sizes on the primary and secondary and the car seems to be running excelent.

Tomorrow I will have to take it out for a spin and see how it runs on the road!

Thanks for the help!