Need help with installing the pcv valve hose connection on california emission car. I am currently restoring a '67 camaro with original 327 4 bbl engine, which came with the smog equipment, road draft tube ( which routes a hose from top back of engine block to air cleaner) , rochester carb, and pcv valve installed in the oil fill tube and routed to the rear of the carburetor. I believe this is listed as a "closed positive ventilation system" First I need to know which side of the carb the hose is properly routed- drivers or passenger side? Is there a bracket which holds the hose out of the way of the choke linkage and/or road draft tube, or on the other side-the throttle linkage assembly? Or does this hose just lay loosely on the intake? Also the hose diameter seems to fit the pcv valve fine, but the other end which connects to the lower back side or the carburetor is to small. Or the nipple out of the carb is too big. Do I need a junction block off the nipple or some kind of a reducer? The nipple seems to be pressed (not threaded) onto the center of the back base of the carb. In case it would matter, I am not putting the smog items back on, and will be running headers. Thanks in advance for all help!

I wouldn't run the smog equipment unless you are trying to make it look original. Even California does not smog that year anymore. I believe yours was probably run from the valve cover to the air cleaner. You should get a PCV valve that matches your engine vacuum at idle.

Once you rip all the smog stuff out you can run the PCV straight to the manifold. You will need a 3/8 hose barb. If all your hoses won't connect you can get vacuum tees off old cars at the local salvage yard. I have a bunch of them that I keep on hand for any future changes.

If you run power brakes you need to keep a seperate 3/8 fitting. You do not want to tie the two together off a "T" fitting.

I guess I was planning on running the pcv set-up as original, without the smog equipment installed. (because of putting on headers without smog set-up). I am also running solid valve covers as original, so I thought the right way (original) is to run the pcv out of the oil fill tube (as original) then hose it to the original nipple on the lower backside of the rochester carburetor. This was how it "was" routed except mine (hose)was on drivers side around the throttle linkage, and others I have seen are on the passeger side around the choke linkage and road draft tube. Which is correct and is there a bracket to hold the hose up and out of the way of these obstructions ? also the nipple on the carb is bigger than the nipple on the pcv valve. (maybe I lost this reducer when I took off the smog equipment) How do I downsize off the carb nipple? This nipple is pressed onto the carb. I could use a larger diameter hose and slip it over the pcv nipple "and valve body", but this doesn't look appropriate. The hose is only supposed to go over the nipple. FYI the road draft tube is the only connection to the air cleaner at this point. (there was a connection for smog hose, but like I said, that is no longer going to be used.) I did'nt know California no longer inspects this year car for smog--interesting. Thanks

I believe yours was probably run from the valve cover to the air cleaner. You should get a PCV valve that matches your engine vacuum at idle.

Once you rip all the smog stuff out you can run the PCV straight to the manifold. You will need a 3/8 hose barb. If all your hoses won't connect you can get vacuum tees off old cars at the local salvage yard. I have a bunch of them that I keep on hand for any future changes.

If you run power brakes you need to keep a seperate 3/8 fitting. You do not want to tie the two together off a "T" fitting.

No holes in the valve covers of a '67... It wasn't until '69 when they placed a pcv valve and breather in the valve covers.

For clarification CA law doesn't require an inspection but if stopped and questioned you could be sent for visual. Legally you are required to have what the car came with...

The brake booster is tied into the manifold at the same place as the tranny, RS headlight doors, AC etc. The only reason the pcv is not into the manifold at the same place is by having it in the base of the carb the crud it pulls from the crank case doesn't end up all going to one runner and cyl to be burnt off.

Need help with installing the pcv valve hose connection on california emission car. I am currently restoring a '67 camaro with original 327 4 bbl engine, which came with the smog equipment, road draft tube ( which routes a hose from top back of engine block to air cleaner) , rochester carb, and pcv valve installed in the oil fill tube and routed to the rear of the carburetor. I believe this is listed as a "closed positive ventilation system" First I need to know which side of the carb the hose is properly routed- drivers or passenger side? Is there a bracket which holds the hose out of the way of the choke linkage and/or road draft tube, or on the other side-the throttle linkage assembly? Or does this hose just lay loosely on the intake? Also the hose diameter seems to fit the pcv valve fine, but the other end which connects to the lower back side or the carburetor is to small. Or the nipple out of the carb is too big. Do I need a junction block off the nipple or some kind of a reducer? The nipple seems to be pressed (not threaded) onto the center of the back base of the carb. In case it would matter, I am not putting the smog items back on, and will be running headers. Thanks in advance for all help!


You have the right idea, I think there were two ways your PVC could have been plumbed. One is the valve is in the fill tube and plumbed to the carb and the other is the valved screwed into the base of the carb. Both ways used a breather off the back of the block. You can get a classic ind catalog online or from most any of the other parts vendors and find the various parts used. With what you know already just seeing the parts in the catalogs will allow you to figure it out. I don't know your exact application but a lot of pieces/hoses were molded with different end sizes etc.

No holes in the valve covers of a '67... It wasn't until '69 when they placed a pcv valve and breather in the valve covers.

For clarification CA law doesn't require an inspection but if stopped and questioned you could be sent for visual. Legally you are required to have what the car came with...

The brake booster is tied into the manifold at the same place as the tranny, RS headlight doors, AC etc. The only reason the pcv is not into the manifold at the same place is by having it in the base of the carb the crud it pulls from the crank case doesn't end up all going to one runner and cyl to be burnt off.

not start an arguement but, my 68 327 has fittings and pvc in the valve covers. I have owned the car for 35 years and I am the second owner.

not start an arguement but, my 68 327 has fittings and pvc in the valve covers. I have owned the car for 35 years and I am the second owner. No problem, I know the '67 didn't and the '69 did. Stand corrected on the '68...

If you have the '67 assembly manual, check out page "K19 A10". I think this is the diagram you are looking for.

If you have the '67 assembly manual, check out page "K19 A10". I think this is the diagram you are looking for.

Actually the AIM section is K24-A2 for a 'Closed System' ;)
K19 is the A.I.R. system.

Here are a couple of old posts discribing the 1967 RPO-K24 systems along with a few other emissions thingys;
http://www.camaros.net/forums/showthread.php?t=55694&highlight=k24
http://www.camaros.net/forums/showthread.php?t=53996&highlight=smog+system

Post back if you have a specific question on any of the above.

Actually the AIM section is K24-A2 for a 'Closed System' ;)
K19 is the A.I.R. system.



Yup, Definitely that one! :thumbsup:

If you have the '67 assembly manual, check out page "K19 A10". I think this is the diagram you are looking for.
Tom,
Actually my system looks more like page "K24 A2" with the hose that routes to the rear. The problem is this picture shows the 2bbl version with some sort of a junction block off the carb. My carb has a large diameter port which is substantially larger than the pcv valve nipple. How do I find this "junction block" (or reducer) ? What would determine if I could route this hose to the front of the carb? Does it matter which way? Or could I route this hose to the "T" junction on the intake manifold where the transmission vacum hose connects to? FYI- I do not have power brakes, so this "T" is a single connection.

You have the right idea, I think there were two ways your PVC could have been plumbed. One is the valve is in the fill tube and plumbed to the carb and the other is the valved screwed into the base of the carb. Both ways used a breather off the back of the block. You can get a classic ind catalog online or from most any of the other parts vendors and find the various parts used. With what you know already just seeing the parts in the catalogs will allow you to figure it out. I don't know your exact application but a lot of pieces/hoses were molded with different end sizes etc.
Dennis,
I do have the system where the valve is threaded into the fill tube and plumbed to the rear of the carb. And I do have a breather off the back of block. All the actual pcv hoses I have seen are the same diameter from pcv to carb. Problem is, my connection (port) on the bottom back of carb is much larger than the nipple on the pcv valve. Should I be looking for a hose that changes in diameter from one end to the other? Or am I missing a junction block (reducer) off this port on the carb? Should I consult someone who restores Rochester carburetors to figure out this rear port or possible junction block ? What actually determines whether this hose goes to the front or rear of the carb? Anyone have any pictures of this backside carburetor hose connection. Thanks

Joel, I was wrong at first~ K24 is the right page and applies to both 2bbl and 4 bbl carbs. The have the 4 bbl drawn in with dotted lines and "L30" is the 327 4 bbl. It looks like the block from the back of the carb is just a 90* fitting. I think the drawing may be saying that with 2 bbl, the hose goes to the rear of the carb and with 4 bbl it goes to the front. Your oil filler neck has one pcv valve, right?


My car uses the system shown on page L30 A3 and just routes to the front of the carb.

Joel, I was wrong at first~ K24 is the right page and applies to both 2bbl and 4 bbl carbs. The have the 4 bbl drawn in with dotted lines and "L30" is the 327 4 bbl. It looks like the block from the back of the carb is just a 90* fitting. I think the drawing may be saying that with 2 bbl, the hose goes to the rear of the carb and with 4 bbl it goes to the front. Your oil filler neck has one pcv valve, right?


My car uses the system shown on page L30 A3 and just routes to the front of the carb.
Tom,
Thanks for the advice and suggestions. Yes my car does have just one pcv valve off the oil fill tube. You mentioned the block on the back of carb is just a 90degree fitting, i guess I need this fitting but not sure where to find one or how to attach it to the outlet tube/nipple on the back of carb. Maybe a place that rebuilds carbs? Currently the lower back of the carb has a pressed in outlet tube/nipple ( which is oversized for a standard pcv valve hose , available in all the parts books). The front of the carb does have a more appropriate tube/nipple in the center bottom that is not being used at this time. (capped off). Maybe I should just route a shorter hose to this "front" nipple from the pcv/oil fill tube and cap the back outlet tube/nipple. Any reason the pcv is routed to the front or back of carb? FYI the carb is a Rochester 4bbl. Thanks again!

Maybe I should just route a shorter hose to this "front" nipple from the pcv/oil fill tube and cap the back outlet tube/nipple. Any reason the pcv is routed to the front or back of carb? FYI the carb is a Rochester 4bbl. Thanks again!

I think that is what you should do and that is correct according to the drawing. The rear port is used on the 2 barrel carbs. I think there was no room for it in the front on 2 barrel carbs and that's why. That makes sense to me anyway.

Good luck!

I think that is what you should do and that is correct according to the drawing. The rear port is used on the 2 barrel carbs. I think there was no room for it in the front on 2 barrel carbs and that's why. That makes sense to me anyway.

Good luck!
I'll try that, Thanks!