Contour Enthusiasts Group Archives Forums Modifications Duratec Performance Terry Q again. The "restriction"

if you want to go with pre-formed plastic tubing why don't you go with the grey plastic electrical conduit. It is made of thermosetting plastic so it can be softened by heating and will harden once cooled. You can buy pre made bends as well in 90, and 45 deg. and I believe it has a heat resistance between 1 and 2 hundred degrees. they are available in 2", 3", 4" and so on. It is also inexpensive. I believe about $18 for an 8' section of 3", and the bends are just a few $ each as well.

The conduits are slip together and can be made air tight by lightly sanding the mating surfaces and then wet assembling them with RTV silicone.

Or you could really chince out an use the flexible aluminum vent ducting, it is easy and quick, but it shows, but if it works who cares, right?

The plastic would need to resist atleast 200 degrees IMO (If not more) with out becoming pliable.
I know PVC piping is not suitable. I do not know any specs on the thermosetting plastic you brought up? Would be good to look into!

Would also be nice if we knew the inner diameter of the upper intake as is??? (largest - dual honed SVT ~ actually any would be a start!) Give a starting point of reference.
2" = 50.8mm - I'm thinking that's pretty big intake runners...

The "pleated" venting duct would kill air flow & velocity. Ribbed for her pleasure is not always the best design...

What about acrylic? Anyone know the temp ranges on that? It would be easy to form bends with(spray down the inside with WD40 and then fill(i mean PACK) with sand before heating and bending so the radii dont get crushed... only thing is how temp resistant is it??
Question ... what are those phenolic spacers I always see for intakes made out of?? If we can find the same material, cutting flanges and then chemically bonding the parts should be a piece of cake....

your idea about acryilic is a good one, but acrylic is not resistant to petroleom products, it sufferes from whats called crazing, and with strong solvents or extended exposure to petroleums will start to disolve. I believe its heat resistance is also low. I remember forming acrylics is school in an oven at 180 degrees.

Phelolic spacers are made out of exactly that, a fiberous material usually fibergalss or polyesther impregnated with phenolic resin and cured under pressure to clamp the lay-up together. You are right about machining it though, it is easy, and takes well to most adhesives.

I don't see whay we don't look into making a prototype out of a hard wood like maple or oak, its common, inexpensive, easy to machine, has a low conductivity, can be bonded easily and so on. The only problem is that wood is fiberous and needs to be sealed to prevent water infiltration and air passing through it, but that should be able to be fixed by sealing it with a sealing paint like KILZ

ooh, phenolic plastics are very heat resistant and could easily withstand the under hood temps.

Nylon is also heat resistant but I think it might be more expensiv than the phenolic but I'm not sure.

Phenolics spacers (and the material itself) came up at the beginning of this thread.

Since I made one already... "Toot, toot"

Problem is phenolic resins need to be press molded & then cured. (like you said) Back to needing a mold!

Wood for a model intake. (since you'd never use a wooden intake) Computers are much easier to use IMO. It draws perfect angles and curves for me...

Oak is not a real good option. (too porus)I think a better is Popular. fairly cheap and easy to work. If somebody has some shamatics of this intake I can look at building it. I use wood all the time.

Well, since the phenolic responds so well to adhesives, what would happen if you made a couple of molds for each half of the runner(it would be easy to clamp and press half an elbow...) and then adhere them together? then youd jsut need to attach them to the flange and center body..... maybe I'm just making this sound to easy in my mind....

The problem is making the molds...

Even if you made one by hand (not very precise!) You would need 4 of them to make the 2 halves. Then they would have to be exact in dimensions to each other to fit together properly. (done by hand to exacting tolerances!)

when I mentioned phenolics, I meant pre made blocks of fiber reinforced phenolic resin. it is about as easy to machine as wood, and like you said responds well to adhesives.

I had another thought today, what about masonite, the brown fiber board stuff they make peg boards out of, just buy the stuff without holes. I think it usuallly comes in 1/4 inch thick sheets, 3 pieces could easily be bonded together to get 3/4 inch, and then machined to the desired demensions.

It could even be made bigger than needed, and then bored out to a size large enough to accomodate a plastic tube or similar with a ID equal to the TB bore, which would be inserted and bonded into the masonite spacer block, to, 1. make a smooth surface, 2. make a good seal as masonite is also porous, and 3. to prevent fibers from being injested into the engine.