replacing original quadrajet with newer model

[dclu1997]

I want to install a 17057204 (1977) to replace the original 7040504 on my 1970 ss 396 chevelle the motor is 100% original but the carburetor well plugs appear to be leaking (hard starting after sitting)the carburetor is original to the car and i don,t want to drill and tap the plugs.should I install the same size jets and rods in the newer carb? the specs on the newer carb are close to the original  Thanks for any help

[Ethan1]

I want to install a 17057204 (1977) to replace the original 7040504 on my 1970 ss 396 chevelle the motor is 100% original but the carburetor well plugs appear to be leaking (hard starting after sitting)the carburetor is original to the car and i don,t want to drill and tap the plugs.should I install the same size jets and rods in the newer carb? the specs on the newer carb are close to the original  Thanks for any help

 Welcome to CHP!

 It is not hard at all to install the new plugs. If you are not up to the task, send it to Cliff. But, seriously, it is a 1 hour job. Plus waiting on the Marine-Tex to harden up. You also need a good tap set and good tapping fluid for the soft metal. Grind off the top of the old plugs, pull the old plugs out, tap and screw-in plugs with Marine-Tex (make sure you get all tapping fluid gone before installing plugs w/ Marine-Tex). That is it.

[carmantx]

The 77 Quadrajet is a nice carb to build from.  It has the APT access through air horn, and the hot air choke you could convert to electric.  It is a different style quadrajet and will need to be set up correctly for your 396.  If you are going to build it for your 396, call Cliff to get the correct parts and modifications required for it to work well for you.  Probably going to need idle tube mods, at a minimum.

[dclu1997]

thanks for the replies   ,i,m kind of a original nut, and don,t want to drill and tap the original carb,thats why I want to make the newer carb work on the chevelle,I will take your advice and check with Cliffs   Again thanks guys, first time I have been on a forum

[Ethan1]

thanks for the replies   ,i,m kind of a original nut, and don,t want to drill and tap the original carb,thats why I want to make the newer carb work on the chevelle,I will take your advice and check with Cliffs   Again thanks guys, first time I have been on a forum

 Not a problem. I would go with Carman's recommendation anyways. Much better in the long run for your application.