1968 Z28 cowl plenum smog tubes
 

Were smog tubes on a cowl plenum car the same as on a open element breather car?

Re: 1968 Z28 cowl plenum smog tubes
 

The drivers side is but the passenger side takes a hard turn to the front on the engine to miss the bottom of the air cleaner.

Re: 1968 Z28 cowl plenum smog tubes
 

Use the original tube,but replace the rubber hose with a 90 degree bend. John p.s. That is what I plan to do when the time comes.

Re: 1968 Z28 cowl plenum smog tubes
 

That sounds like a good idea,I have been told a certain Nova smog tube will work but just more money

Re: 1968 Z28 cowl plenum smog tubes
 

The tube will still hit the bottom side of the breather, been their and done that, be better to get a different tube.

http://www.fototime.com/D85A3241097B0DE/standard.jpg

Re: 1968 Z28 cowl plenum smog tubes
 

If you use a 69 pass side tube it bends 90 deg before the valve screw on. Not correct (obviously) however it should work.

Re: 1968 Z28 cowl plenum smog tubes
 

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

Re: 1968 Z28 cowl plenum smog tubes
 

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.

Re: 1968 Z28 cowl plenum smog tubes
 

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

Re: 1968 Z28 cowl plenum smog tubes
 

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.