I have the original intake tubes for my 86.5 but keep them off the car because they are NLA and prefer to preserve them. I used 3 inch brake duct hose as a substitute and loved the way that looked but it did not hold up where it passed through the pinch point on the passenger side near the hood switch.

I did some poking around on the internet and found another solution that ends up looking exactly like the plastic corrugated tubes used on OB’s. I started with plastic 3 inch dust collection hose here:

http://www.highlandwoodworking.com/flexhose3.aspx

They also sell a straight connector to splice two sections together that provides an opportunity to have something solid and durable to slide over the tubes on the top of the timing belt cover. These parts are here:
http://www.highlandwoodworking.com/s...onnector3.aspx

To reproduce the rubber cover over where the tubes join, you need to cannibalize two 3-inch diameter shielded no hub pipe couplings. I got mine at the local big box home improvement store. They look like this:

http://www.lowes.com/ProductDisplay?...llow&cId=PDIO1

or

http://www.homedepot.com/p/Fernco-3-...0-33/100372287

or

https://www.fernco.com/plumbing/shie...-hub-couplings

You will also need a heat gun or a wife who will allow you to dunk the hose in boiling water and wine bottle or a 1 liter Coca Cola bottle.

Take the rubber section out of the two flexible pipe couplers and turn them inside out. There is a ridge down the middle that fits between the two pipes that are joined by the coupler when it is used for its intended purpose. Cut off the ridge as close to flush as you can. Turn the sleeve back to having the original outside out. Punch a hole in the sleeve for the timing cover pipes. I made a punch by sharpening one end of a short section of ¾ inch copper pipe. I then used a hole saw to cut a 25 mm hole in the middle of the plastic coupling. I had to shape that hole a bit with a round file and/or a dremel to get it to fit over the timing cover vent pipe.

The final challenge is getting the plastic hose to fit over the round ends of the scoops on the fan shroud/radiator header. The plastic hose needs to be stretched to fit over the scoop ends.

I cut the long sections of the tubing first and found that I had enough hose left over to make 4 short sections that fit between the timing covers and the scoops. You can stretch one end of these short sections by heating it in boiling water or by using a heat gun. After a few minutes in the boiling water the end should have softened enough to take a stretch. Put your wine or coke bottle on a solid surface and put the hose over it and push down. This should enlarge the end enough to get it over the scoop fitting. The hose has a lot of “memory” so let it cool a bit before pulling off the bottle.

Put your rubber sleeve over the plastic connector and then maneuver the hoses onto the connector.

Pictures below.

 

Nice!!! Many guys searching for NLA tubes will love this!

 

Win !!!
This is just great !
Thanks so much for linking to your parts sources.
My tubes are getting kinda toasty and this is a super solution.
Thanks

Dan

 

Very nice!

Nice looking, inexpensive alternative, to the originals. Would work great for guys that have the older sytle tubes. Your set up looks like my 78's tubes...and they are no longer available...so this is a sweet option for an extra set.

Thank you, for sharing.

Brian.

 

I've seen these on Otto's car, and they are fantastic and look very much like the nla early tubes. I keep my original ones off the car for the most part now in order to preserve them, but I will make these and use them too in order to keep the correct look. Thanks for the post Otto!

 

That's not an OB.

For OBs and all 928 through '84 the 3" brake duct works fine.

 

Nice work on the DIY.

I have 1 of the old tubes off my '79 5-speed. If anyone is interested in it, make me an offer. I don't need it with my supercharger setup, so it's sitting in my parts pile. I can inspect it and take photos. Email me at petza914@gmail.com.

 

Petza...
I may be interested, depending on condition.
Waiting on a pic.
Nevermind.....just noticed the year.

 

Pete - email sent.

 

Glen - Otto's set up is the best aftermarket/DIY set up that I have seen that duplicates the look of the early tubes. Here is a picture of mine for reference. Also I am in the market for extras, if anyone has any to sell.

 

Thank you,good information which i will take advantage of.

 

Yes, thank you. They look great.

 

Isn't There is an old thread using these Mercedes tubes with coupler to connect 2 tubes together. 4 tubes total needed and 2 couplers.

http://www.ebay.com/itm/111580699111?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

When they find Hoffa, he'll have a S3 tube in each hand.

 

Agree with Ed...When I saw Otto's car at a gathering I thought the tubes were new OEM replacements and asked him how he found them. Otto's got some other creative solutions on his car. I like what he did to clean up the defroster vents where the leather had started to dry out and pull away. To anyone who doesn't know 928s his cosmetic treatment can pass for original.

Otto's car is one of my favorite 928s. The dark blue and pearl interior are a great special order combo.