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Discussion Starter #1
Hi, all. I posted this a few days ago and didn't get any responses so I thought I'd try again. I've got a 68 GT 350 with the J-code 302. Cobra Hi-rise intake and Holley 600 CFM carb. Where does the PCV hose attach? I've read the back posts that state it will make a cylinder run lean if I put it to the intake, yet there is no spacer(like on regular Mustangs) to plug the hose into. Someone suggested a phenolic carb spacer. Is that correct or just a fix? I'd like to keep the car as original as possible. There were 1657 small block Shelbys built in 68, somebody has to know the true story and I bet it's a VMFer!!! Thanks.
 

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Discussion Starter #3
The oil breather cap is connected to the back of the Cobra air cleaner. The PCV needs some type of manifold vacuum. On this car I'm not sure where it goes though.
 

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I started a reply to this yesterday but never posted it.

All 68 GT 350s had a carb spacer plate that the PCV hose connected to. This includes 4 speeds and automatics. On the GT 350s that were built before the middle of March 1968, the spacer plate was ~1" tall and made out of aluminum. ALL of these GT 350s came with Ford cast iron intakes and Autolite 4300 carbs. After Ford issued the intake recall (March 1968), the GT 350s started coming from the factory with the Cobra aluminum intake and either a Holley carb (4 speeds) or an Autolite 4300 carb (automatics). The spacer plate on these GT 350s was ~3/8" tall and made out of resin/plastic. At the back of this plate was a metal port that is round on the PCV hose end and tapered into the spacer plate. For GT 350s that answered the recall notice, the intake setup was replaced with the Cobra aluminum intake, new spacer plate (original 1" would not work on the Cobra intake), and either the Holley carb or the original Autolite 4300 carb.

This spacer plate has long been obsolete and few if any NOS ones may still exist. I will take a picture of an original, correct spacer plate and post it tonight for you to see. I have found that the boss 302 spacer plate with some modification works the best as a replacement.

Obviously, your spacer plate is missing and you may wonder why. Here are my observations as to what may have happened. The 3/8" spacer plate is somewhat brittle and easily breaks where the metal tube goes into the plastic, thus during carb rebuilds a mechanic would toss it and re-route the PCV hose to one of the ports on the rear intake runner. On recall GT 350s, the Ford mechanic simply did not follow the TSB and never installed the correct spacer plate and re-routed the PCV hose to one of the ports on the rear intake runner.

BTW, you are correct about the routing of the oil breather cap hose to the air cleaner base plate.

Regards,
 

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BTW, I see your GT 350 is a 4 speed. Is the smog stuff still attached? Another interesting fact is all 68 GT 350, 4 speed Shelby's came with smog assemblies. It was the only way these cars could pass emissions.

Most previous owners removed the smog stuff and tossed it making for a difficult correct restoration today.

Regards,
 

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Discussion Starter #7
Pete,

Yes all the smog stuff is there. The PO put it back on so he could get it licensed in CA then they changed the rules so he just left it on. I just private messaged you.
 
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