TBI/center bolt valve cover options

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Scruffy49

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Found these on Fleabay.
https://www.ebay.com/itm/186737828145

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They look pretty nice and less squared off than the typical center bolts.
Those are what is going on my carb conversion Vortec 350, with the passenger rear oil filler assembly off a factory carbed 4.3L V6… Replacing the stock solid “pop in” oil filler plug with a “pop in” breather… PCV will be in the driver side valve cover, plumbed to a 650cfm AVS2 “carbon dater”…;)
 

1lejohn

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How so?

Placement of the breather/pcv/oil fill is not critical. GM themselves moved them from location to location depending on the year and car/truck model. All that matters is that the breather is on the opposite bank as the pcv valve.

Here's two typical ways GM did it. The breather and PCV swapped sides and the oil fill was driver front or driver rear.

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Those are the ones I'm running on my truck. The ones I had come from a 92 F-Body.
 

Gander

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350 TBI
One thing I’m wondering about the center-bolt valve covers. The drivers side cover I’ve got doesn’t seem to be threaded for a screw-on cap and doesn’t have the cutouts for a bayonet-style cap. When I got the truck it just had a generic press-on rubber cap which was of course all dried out and seeping so I replaced it with a FC140 cap.


I’ve actually got a couple questions about it. First, has anyone else seen centerbolt valve covers with press-on caps? I’ve seen plenty with the plastic screw-on cap and I’ve seen a couple with the old metal bayonet blade style cap but I’ve never seen them with press-on caps before until this truck. Second, if anyone has, is there any way to use the oil filler extension you see on some of the later motors that use the center bolt style covers? Or do those extensions thread in?
 
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