1968 Z28 cowl plenum smog tubes

[firez]

I can not hink why GM would not have made a camaro specific one for this application

[bluel78]

Im still learning but I would think the tube would be the same. The cowl plenum was an over the counter piece/ dealer installed and did'nt come with a smog tube. They probably assumed if you installed the cowl plenum setup you would also buy headers, therefore no interference with the smog tubes.

[302moz]

Plan b shorten the tube.Then the check valve will be lower. Send it to Bill and have it replated. John

[jack hatch]

I have a set of smog tubes that I acquired from Jerry MacNeish years ago. The passenger side tube is rare and built specifically for the Cowl Plenum installation.The passenger side tube sweeps 90 degreees in the direction of the tube itself pointing to the smog pump. It also starts its sweep at the firewall end of the tube to allow room for the hose to connect to the smog pump The drivers side is the same.

[Charley Lillard]

Here is what Jerry posted on CRG.

"One set of std. tubes were used on the 68 Z28 and they do not work with a CP air cleaner. The right side will not clear the duct.

These CP air cleaners came in the trunk and it was up to the dealer or new owner to deal with installiing the air cleaner. That meant removing the smog stuff. There is a right side Nova tube with 90 degree angle that will work but it is not technically correct.

Jerry"