68 327 hipo venting
Thread Starter
Le Mans Master
Joined: Jun 2019
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From: Loveland
68 327 hipo venting
I wanted to bring the engine venting system back to original. The right side valve cover just had a filter on it, so I added the vent tube to the underside of the air cleaner. The left side valve cover has the PCV valve (replaced new) and a hose to the bottom of the carb. Took it for a drive and after it got warmed up, ran like crap. It didn't before. What I don't understand with this setup, both sides are under suction. Doesn't make sense to me.
I reinstalled the filter on the rt side valve cover and will test it today.
PS. I ordered the ACDelco hipo PCV valve 19303069 2057 for $5 and got a box of 10.
I reinstalled the filter on the rt side valve cover and will test it today.
PS. I ordered the ACDelco hipo PCV valve 19303069 2057 for $5 and got a box of 10.
Last edited by kodpkd; Apr 22, 2022 at 02:07 PM.
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From: SW Florida.
it could have had a plugged up pcv valve and adjusted to it. and the pcv now working is acting like a vacuum leak. block off pcv and see if it runs better. also possible the tube to the air filter has no restriction while the little filter on the r valve cover could have been restricted. you could also try clean and reinstall old pcv. just cuz something is new doesn't mean it works correctly.
Last edited by derekderek; Apr 22, 2022 at 03:51 PM.
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I wanted to bring the engine venting system back to original. The right side valve cover just had a filter on it, so I added the vent tube to the underside of the air cleaner. The left side valve cover has the PCV valve (replaced new) and a hose to the bottom of the carb. Took it for a drive and after it got warmed up, ran like crap. It didn't before. What I don't understand with this setup, both sides are under suction. Doesn't make sense to me.
I reinstalled the filter on the rt side valve cover and will test it today.
PS. I ordered the ACDelco hipo PCV valve 19303069 2057 for $5 and got a box of 10.
I reinstalled the filter on the rt side valve cover and will test it today.
PS. I ordered the ACDelco hipo PCV valve 19303069 2057 for $5 and got a box of 10.
You have to adjust the idle mixture screws after hooking it up.
Thread Starter
Le Mans Master
Joined: Jun 2019
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From: Loveland
I'm not sure why the air in the air cleaner would be at atmospheric pressure, when the carb is sucking all that air onto the engine. Suck equals negative pressure.
New and old PCV valve were the same. I installed the filter back to the rt side valve cover and seems to run just fine
New and old PCV valve were the same. I installed the filter back to the rt side valve cover and seems to run just fine
Is my vette stock?? HAHA
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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The air inside the air cleaner isnt being affected buy the air inside the caburetor unless your air filter is clogged and creating a vacuum inside the housing. As for switching the hose to a filter you maybe ceating a restriction enough to effect the AF mixture so that your idle mixture screws settings are being affected. Its as if you are plugging and unplugging a vacuum leak. Your filter is less of a leak than the open hose.
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still at atmo until it passes the throttle plates. it is movin around. may even have one down from 14.7 to 14.69-something, but still at atmospheric pressure. if your air in your air filter is pressure-dropped, you need a bigger air filter. way biger...
Thread Starter
Le Mans Master
Joined: Jun 2019
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From: Loveland
So the air is being sucked into the rt valve cover (from the filter) because of the suction of the left valve cover (PCV) side.
One way flow,,,,, into the RT side and out of the LT side valve cover.
One way flow,,,,, into the RT side and out of the LT side valve cover.
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Is my vette stock?? HAHA
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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Correct
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Melting Slicks
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Unfortunately, using the open type rocker arm cover breathers rather than the closed PCV system causes a fine engine oil mist to coat the engine. https://www.corvetteforum.com/forums...ve-covers.html
Thread Starter
Le Mans Master
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From: Loveland
But I still have the PVC on the LT side.. The only difference is the RT side is getting it's filtered air from a little filter rather than a big filter.
My valve covers are the original style baffled covers.
My valve covers are the original style baffled covers.
Last edited by kodpkd; Apr 25, 2022 at 09:10 PM.