Divided Plenum Manifold HOW-TO

[Matt_vp]

twin tb

would u be better dividing the banks and giving them each a intake and tb

 

[VT-565]

He also said the a long runner tuned manifold would be pretty easy to make using aluminium pipe and bending it with sand inside, he reckons you can make all sorts of crazy stuff with it

Foam, sand bending has been in practise since day dot. it is an excellent way to bend pipe and tube while keeping a constant internal cross sectional surface area. however, it can be quite tricky to do. i notice that the new harley v-rods use a water bending method for the new bike frames, where the pipe is pressurised with water than bent, keeping that constant internal diameter. cool stuff indeed.

 

[greenfoam]

I saw that documentary about the V-Rod last year (I had never even heard of the bike), I got enchanted watching it and then I drove down the street straight after watching the tv and saw one parked in front of the pub!!!!! my eyes nearly popped out of my head. I read about sand bending a while ago too when I was going to make some extractors but it didn't hit me that I could use it to make a manifold with aluminium tubes

 

[greenfoam]

would u be better dividing the banks and giving them each a intake and tb

That's the plan if I make a second manifold like in that drawing ^

 

[Matt_vp]

i took a manifold to work tonite and started making one, but i chopped the top off it, and fabed a taller one so i can put a tb on each side in the middle. Might add some photos 2morrow but need sleep now.

 

[greenfoam]

If you can try and extend the runners, even another 3 inches will work wonders

Here's some simulations, All engines are buick V6 with 24 inch extractors, and a good dual cat exhaust.

Image 1) Current is a stock manifold like I have with a divider, Last is the stock manifold (open plenum)

Image 2)Current is stock manifold. Last is split manifold with 6 inch runners

 

[Matt_vp]

all i need is some basic demensions and im sure it can be done.

 

[greenfoam]

Well I'll get back to you on the plenum size but You could extend the runners like this. If you have the tools to do that, it would be a wicked manifold throttle bodies could be both at the back or front or sides? 6 or 7 inch runners would be choice and still fit under the bonnet

 

[warney]

you have such paitence foamy

can i have your babies?

 

[greenfoam]

If you are really Adriana Lima, and just using a silly name because you like Commodores, then yes