VA-128 Best way to make?

Brantel · #1 09-17-2008, 06:38 AM

I am getting ready to hang my engine and the builder installed a steel 45? fitting in the oil pressure port but it is not a restrictor fitting.

My question is: Can I modify this one by some method and if so what is the best method to make this a restrictor fitting. I have seen somewhere instructions to insert a rivet with a hole drilled in it and cut it off.

Waiting on Van's to ship me a $17.20 fitting plus shipping and handling stinks if I can modify this one into the same thing for nothing.

I understand that the VA-128 is punched somehow to hold the insert in the fitting????

What size hole is the best?

647jc · #2 09-17-2008, 07:22 AM

I made a restrictor fitting for my MAP sender according to instructions supplied by someone on this forum (I think). I don?t recall the exact sizes but basically I tapped the fitting (aluminum in this case but should work with steel) with I think a #8 or possibly #6 tap. Only tap to the depth of about 3/8?. I then drilled a very small hole, size probably not important down the shank of a #8 or #6 machine screw, try to keep it centered and be sure and drill deeper than 3/8?, at least ??. Next, screw the screw into the tapped fitting and torque it down then cut off the part of the screw left sticking out with a dremel tool. You probably shouldn?t tap the end of the fitting that screws into the engine. Anyway, I copied the process from someone else and it worked well for me.

noelf · #3 09-17-2008, 04:59 PM

This is not a comment on how to make a restrictor fitting. The 45-deg fittings I got from Van's were quite nice. The fittings are steel, and the restrictor is "pined" into the fitting. It looks like they used a punch tool with points spaced every 90-deg. This results in four crimps in the steel fitting and pinches into the metal restrictor.

Also, I hope you ordered one for the fuel pressure sense line as well.

And you might want to consider what you want to use in the manifold pressure line (if used). The restrictor here is used to attenuate the pressure (vacuum) pulses before they reach the MP sensor. For my installation, I could not use the 45-deg fitting from Van...the geometry that I needed required a straight fitting at the #3 cylinder head.

noelf · #4 09-17-2008, 06:45 PM

Found my Tony Bingelis "Firewall Forward" book...page 229 shows how to make several different versions of the restrictor fitting. The one I like the best is to use a brass fitting, filling with solder, and drilling a .040 hole...

LifeofReiley · #5 09-17-2008, 06:54 PM

Quote:

Originally Posted by noelf

Found my Tony Bingelis "Firewall Forward" book...page 229 shows how to make several different versions of the restrictor fitting. The one I like the best is to use a brass fitting, filling with solder, and drilling a .040 hole...

This is a great method, one I learned about 14 years ago and forgot totally about. Thanks for the brain shake!

Brantel · #6 09-17-2008, 07:11 PM

Is this the best place for a brass fitting? A critical part with a hose hanging off of it?

LifeofReiley · #7 09-17-2008, 07:20 PM

Quote:

Originally Posted by Brantel

Is this the best place for a brass fitting? A critical part with a hose hanging off of it?

Brian,

The oil pressure hose from Van's is pretty small and very light weight. I personally would not be concerned. You're going to support the hose with clamps too. I don't believe Tony B. was very concerned either.

I just went out to the garage and looked at an E2D accessory case, the OP fitting is brass right off a certified plane.