Adding a vintage oil fill tube to a modern intake


We machine our new Edlebrock intake to accept an oil fill tube and look the vintage part!

Back before PCV valves were standard lexicon among hot rodders, venting a motor was oftentimes a simple matter of letting the crankcase vent to the atmosphere via either a road draft tube or a breather apparatus of some sort. When it became passé to dump raw hydrocarbons into the atmosphere, more exotic methods were adopted. If you’re building an engine that yearns to identify with a certain era’s aesthetic, like the 383 that we’re building, then simple things like crankcase ventilation and oil fill start to become important build aspects.

And what better way to achieve said aesthetic than to incorporate an oil fill tube to a modern intake manifold? To get the fuel into our motor, we’re going to use an Edelbrock Performer RPM intake manifold. While outwardly similar in appearance to an original four barrel manifold from a 283, it features a port design that is 100% 21st century technology, providing power like a single-plane and throttle response like a dual-plane. Couple that with the ability to add an oil fill tube for that vintage look and you’ve got the best of both worlds.

Unfortunately, if you want to add an oil fill tube to your Edelbrock manifold, you’re going to have to approach your local machine shop with a 6-pack and a smile as Edelbrock doesn’t offer it “out the door”. They do however offer everything it takes to make a modern intake look the part on a vintage motor, which is worth its weight in salt.

For our 383 build, Edelbrock sent us everything we needed, intake, tube, and breather cap, and we did the rest thanks to our trusty Millrite milling machine. There’s just no substitute for the right tools is there?! CC

Sources:
Edelbrock
(310) 781-2222
www.edelbrock.com
Eastwood
(800) 343-9353
www.eastwood.com
Here’s our Edelbrock Performer RPM intake before any modifications have been made. Note the cast pad at the front of the intake that allows the machining of the oil fill tube.
The first step is to set up the milling machine. This meant finding the proper angle of the pad’s surface and adjusting the machine to suit. For our setup, 25-degrees was the magic number.
Edelbrock specs a hole size of 1.250-inches for the oil fill tube. An end mill of similar size makes simple work of the procedure; however we were not so lucky. So, we started by drilling a clearance hole in the manifold, followed by a 1-inch bore cut by a corresponding end mill.
For any boring work (no pun intended!) where I don’t have a corresponding end mill to give me the proper finished diameter, I turn to my Criterion DBL-202 boring head to get the job done. Adjusted to bore the exact diameter hole (1.250-inch), it was a simple matter of running the head through the intake and we were ready to install the tube.
The machined hole checks out perfectly and we’re ready to install the oil fill tube.
First, the intake manifold is shot in Eastwood’s Chevy Orange High Temp Engine Paint, while the tube is shot is my favorite Satin Chassis Black before taking a nap in the freezer. Letting the tube chill for a few hours allows it to shrink ever so slightly, while the intake remained room temperature. This made driving the tube into the machined hole a simple affair, accomplished by a 2×4 and a mallet. The result is a combination that looks more at home on a vintage 283 than a modern 383 stroker motor.