Need a source for small diameter ovalized tubing.....

[blykins]

Got a Tunnel Port intake that's gonna take some modifying.  The round tubes that are in it are about 5/8" diameter.  I'm looking for some ovalized tubing to help with pushrod clearance.

[Heo]

i bought oval tubing a long time ago, bigger though than that
but they where listed as aircraft tubing at the steel suplier
if that is any help

[jayb]

For my tunnel port intake adapters I use .060" wall 3/4" OD tubing, then squeeze it down in a vise to get an oval profile.  I machined an arbor to drive them into place, but I've sent some tubes out for people to sleeve intake adapters that have been ported into the pushrod holes, and the squashed tubes will go in without the arbor if you are careful...

[scott foxwell]

You can put round tube through a roller if you know someone who has one. That does a nice job of making oval tubing.

[67gt350]

Brent, try doing a Google search for oval wardrobe tubing !! Believe it or not it is available in 5/8 -30mm H -15mm W length can be specified. Price is around $25.00 for a 30 inch piece. You say you need it for clearance but K&S Precision Metals has a streamlined tube that is available in 5/8 and 3/4 not sure but the shape may offer a flow advantage ?? Hope this helps..

[blykins]

Thanks to all for the options.

67, thanks for the lead, I'll check it out.

Jay, do you have any tubes made up?

[jayb]

No, but its trivial to do it.  Just get the 3/4" tubing (I buy it at the local building supply store), and squeeze it in the vise.  Bevel one end to get it started in the pushrod hole.  Green Loctite to seal.

[blykins]

Still thinking through this one. 

If I stack another set of intake gaskets on, everything clears.   However, the intake was cut to perfectly match the ports up with a single gasket thickness.   If I lay the intake on without bolts and cycle the engine through, the intake pushrods will move the intake up and down. 

The heads had been extensively milled before I got them.  Most of the thumbprints were gone.  We did a .005" pass to make sure they were perfectly straight and smooth, and to equalize chamber volumes between heads.

The exhaust pushrod holes will be easy to fix on a mill.  The intakes will be slightly more difficult. 

It may be easier to drill/cut the existing brass tubes out, mill the hole into a "slot", then use an aluminum tube in the correct position, and weld it at the top and bottom.   My guess is that the tube needs to be moved "up" about 1/8" to center the pushrod in the hole.

This is a hydraulic roller engine with .580" lift.   With T&D rockers, I'm using a 5/16" diameter pushrod.

[jayb]

Sorry I couldn't respond in detail before, been buried in my Shelby project.  I dug around this morning and found a couple of spare pushrod tubes.  Here's a photo of my installation tool, plus the tubes, which have not yet been fitted to the tool:



The tubes are 0.060" wall 3/4" OD aluminum tubing.  I cut them to a 3" length with a tubing cutter, then deburr the ends.  Next I stick them in the vise and start to squeeze them, until the installation tool will slide in, as shown:






After the tool is all the way in I squeeze down the vise the rest of the way, then release it and take the tube off the tool.  The end looks like this:




Next I bevel one end of the tube in the grinder to make for an easier fit into the intake:




Finally I polish up the tube in the deburring wheel.  It is shown here on the installation tool, ready for installation:




All there is left is to pound it into place in the intake.  I get the tube most of the way in, then run a circle of green Loctite around the top and the bottom, so that when it is pounded into the final position the Loctite has a chance to wick into the joint and seal.  Finally, here is the size of the hole that I machine into my intake adapters to fit these tubes:




I hope that helps.  If you want me to send you the two tubes that I have, and the installation tool, text me - Jay

[blykins]

That's pretty slick.  I may take you up on that, give me a few days.

[482supersnake]

http://www.ebay.com/itm/427-Ford-Tunnel-Port-Airfoil-Intake-Tubing-/302482070843?hash=item466d561d3b:g:WuQAAOSwRsZZ223r&vxp=mtr

This just popped up on Ebay.