worked up the prototype version of the Y pipe for the dutra duals, for the D-150

for the prototype used a section of the foam insulation that goes over water pipes,, inserted doubled coat hanger wires to give it some memory when bent,, added masking tape to give the radius better form. The intent is to have a model,, I can take to a couple of shops, so when they are quoting the work, I can show an example of how I want the final product to be shaped
http://www.flickr.com/photos/13718356@N ... 782622638/

I started with a six foot length of the insulation, cut it in half, so currently each pipe is 3 feet long, is 3 feet a reasonable length for the exhaust pipe ahead of a collector? I can shorten it six to 10 inches or add a foot, would one or the other be better for performance. I am trying to maximize low end torque with this build.

thanks

You mean you're going to miss out on the fun of driving your truck to the exh shop with open manifolds???

3 ft is about right for low end performance, but I have less data with Dutras than headers...

Lou

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Home of Slant6-powered fun machines since 1988

I'll need to drive the truck with the manifolds open to a shop,, it does have a nice bark to it,,,the foam parts are real close,, but it is not real stable and can be easily distorted,, the purpose of the foam parts is to be able to show the shop, my interpretation of an ideal pipe routing,,

I think you may get a better result if you make the pipe on the right side have a bigger radius. So have it curve towards the other pipe more like a side ways parabola, or have it connect to the other pipe even closer to the fire wall.

Just my input, looks like fun .

Neat idea........thanks. Been pondering these pipes myself.

the Y pipe install was completed today,,

http://www.flickr.com/photos/13718356@N ... 782622638/

the exhaust sounds nice,, real quite at idle,, gets into a higher pitch raspy note around 4K,,motor really revs a lot freer

See you on the dragstrip soon - no excuses!!

Lou

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Home of Slant6-powered fun machines since 1988

Insulation and wires; nice work!
We used a a bunch of small-diameter flexible (vacuum cleaner?) hoses from a container, and punched holes with regular intervals and filled them with polyurethane insulating foam from a spray can. They could be formed while hardening, but got a bit hot from the hardening process and slightly deformed in places, but the curves was the main thing. A friend of mine still has a set hanging on the garage wall, painted silver! He use to tell people they are some experimental german racing headers...

Imagination rules!

Olaf.

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Aspenized

Good job! Can't wait to hear it!

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66 Lil' Red Piggie Valiant (Mater Crusher) - Thanks Zilla!!!!! 72 Demon (Number 1 Son's)

Or T it into the front pipe like I did. Yours is similar otherwise. I love the sound of a Y pipe into a single versus true duals. Eliminates a lot of drone.

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If it was easy, everybody would be doing it.

I am just guessing,, but I bet the "a side ways parabola" comment is in reference to the Y pipe that Doc has posted a photo of.

The set up that I did is for a D-150,, I have a lot of room between the motor-frame rail -steering box,, that allowed me to exit the manifold straight out to a large radius and still have starter clearance,, doing a y manifold in an A body would require the side ways parabola like Doc has shown.

you can see I had plenty of room to run the pipes side by side and the collector flat,, I believe Doc has the pipes over and under and the collector in the stacked position,,