TBI Valve Cover Swap

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TruckCo

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Hey all,

I was looking at dressing up my engine. I have a 87TBI that has a threaded oil cap on the driver side. It also has a gromet with what looks like a pcv line that runs to the rear of the intake. On the passengar side its got the same style fitting only it goes to the front. Id like to get the attached valve covers below. Will these work? I also attached a photo of what my setup is, only the oil cap fill is on the driver side not the pass side. Just wondering how i will “plumb” this up. Thanks!
 

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bucket

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You would use a standard aftermarket style push-in oil fill cap, along with pre-'86 style pcv grommets.

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TruckCo

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You would use a standard aftermarket style push-in oil fill cap, along with pre-'86 style pcv grommets.

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Bucket thank you are their diameter sizes so i know exactly what to order?
 

TruckCo

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These holes are clearly in the wrong spots. Am i able to delete the pcv hoses and just put vents out of these holes? Help!
 

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bucket

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These holes are clearly in the wrong spots. Am i able to delete the pcv hoses and just put vents out of these holes? Help!

You can put those grommets into different holes. Use the cover with two holes on the passenger side. It will get the oil fill cap and the large hole grommet for a breather. Use the small hole grommet on the driver's side, with the pcv valve.
 

bucket

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You'll also have to forgive me, as I'm going off of memory. I'm currently out of town and away from everything.
 

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You'll also have to forgive me, as I'm going off of memory. I'm currently out of town and away from everything.

Bucket this is my setup. I need two for the driver side and a fromt hole for the driver side for the pcv or whatever. Each valve cover currently has a line. Pass side front cover goes to the front intake, driver side rear cover goes behind the intake. This is my delema. One cover only has one hole so im wondering if i can safely delete anything. Also do both sides have to be vented or can just one side be? Also where the new cover gromets are there is a thing underneath and i domt know what purpose that serves. Maybe a splash guard. Just need some help and insight thank you!
 

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bucket

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I forgot that the truck covers are set up a bit different from the car type covers.

But basically all that matters is you have a PCV on one side, and a breather on the other side. The oil fill can be on either. The oil fill hole is the one without the baffle on the underside. You can adapt the little plastic factory breather to the valve cover, or simply run a universal type breather in the valve cover.

Placement doesn't need to be exactly as factory. GM had other setups too, like this:
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TruckCo

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I forgot that the truck covers are set up a bit different from the car type covers.

But basically all that matters is you have a PCV on one side, and a breather on the other side. The oil fill can be on either. The oil fill hole is the one without the baffle on the underside. You can adapt the little plastic factory breather to the valve cover, or simply run a universal type breather in the valve cover.

Placement doesn't need to be exactly as factory. GM had other setups too, like this:
You must be registered for see images attach
Thank you so much for clarifying. I think id rather have a breather and less lines. That way i can just have the pcv. I assume mine being an 87 they sent the breather back to the motor for emissions. But deleting it will Give it a cleaner look. Which one is the pcv in my photos and that wont trip codes correct?
 

bucket

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Thank you so much for clarifying. I think id rather have a breather and less lines. That way i can just have the pcv. I assume mine being an 87 they sent the breather back to the motor for emissions. But deleting it will Give it a cleaner look. Which one is the pcv in my photos and that wont trip codes correct?

Your PCV is the one on the passenger side. The other one is the breather... all it does is recycle any oil vapors back to the air cleaner base so the engine can burn it. My Camaro engine pictured, the breather is on the passenger side and it goes to the air cleaner housing itself. It does the same thing. If you run an open type breather, it will simply vent to the atmosphere.
 

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