John Meany (One of the Owners of the "Big Stuff EFI system and the original inventor for two other well known EFI systems) ran a Twin Turbocharged Mopar at one point. Intercooled deal.

He had the dual turbo inlets in the bottom of the inter-cooler tanks, then thru the intercooler brick, then to a common upper tank. The Throttle Body attached very close to the inter-cooler tank and then a run of large tubing went from the outlet of the Throttle Body to the flange on the intake manifold.

This added a bit more Plenum Volume to the system and slowed down the air speed before the air went into the intake manifold.

Two benefits. Zero Blade Angle effect and more total manifold volume with lower inlet speeds/lower manifold height so air distribution to the runners was very good.

Tom V.

 

Great, that's what I hoped you would say. Makes sense to me and it's easily done. Thanks!

 

Hi Tom, I had one more critical question that has just come up. The tuner has recommended that I place individual wet nitrous nozzles in each runner instead of a nitrous plate on the front of the plenum. He says we it will make sure the nitrous and fuel is evenly distributed. Makes sense and it doable. I may planning for up to a 250 shot of nitrous to reach 1000 whp.

One idea would be to use a annular (straight firing) nitrous nozzle and place the nitrous bung directly underneath the fuel injector bung, both essentially firing to the center/bottom of the runner. Will this disturb the injector spray pattern since the nitrous is under so much pressure when it sprays out? With this design the injector and the nitrous nozzle would not protrude in to the runner, they would be flush with the runner wall.

A second choice would be to use a standard 90 degree nitrous wet nozzle and place it as low in the runner as possible. This design would have the nozzle protruding to the center of the runner and aimed down the center of the runner. I don't like the nozzle being in the runner disrupting air flow and I don't like the idea of the injector spraying the back of the nitrous nozzle.

A third choice is to mount the 90 degree nozzle through the side of the velocity stack inside the plenum, then use a bulkhead for the nitrous and fuel lines on the outside of the plenum, again the nitrous spray may disrupt the injector spray pattern since it would be firing direction on top of the spray cone.

A fourth choice is a spray bar inside the manifold which is my least favorite idea since I know nothing about installing one properly. I could do my home work though and figure it out if it's the best option.

What do you recommend? Do you have a better idea? Thanks in advance

 

I like 90* nozzles close to the bottom of the intake. Looks like there's room in the drawing too. you can control how far they protrude by your bung installation.

 

Nitrous gas makes a great mixer of fuel and air especially with the nitrous upstream of the fuel injector.

Nitrous gas does flow backward and you do not want the gas blocking the fuel spray to the cylinder.

Putting the injector spray in the center of the port, is an attempt to try not to hit the walls with a lot of fuel that then will then NOT be mixed well with the charge air.

Assuming that you can just add NOS to the fuel spray and increase the fuel flow from the injector by upping the duty cycle may not be the best deal, especially if a EFI injector stops working. Big Boom coming next.

Better to work out the boost and fuel stuff as one deal and work out the NOS/fuel as another deal added to the process. less chance on bad mistakes.
Also a BIG burst panel is mandatory with Boost and NOS.

Tom V.

 

Thanks for the input!

 

Burst plate, I hadn't thought of that, good point.

We will be dialing in the boost and fuel first before doing anything with the nitrous. Also I would be using a wet shot of nitrous, I wouldn't risk a dry shot.

I do however want to get the bungs mounted while constructing the manifold so that part is ready when we are. From your comments I'm assuming that your suggesting to put them either mounted through the side of the velocity stack using a 90 degree sprayer (aiming it directly down the runner) or to build a spray bar above the stacks?

 

I would put the NOS injectors (example Pro Fogger) a couple of inches below the injector Nozzle Discharge Opening.

The Pro Fogger type nozzle tends to mix the NOS and Fuel very well and the discharge should not affect the normal fuel injection spray to much as the Fogger will
be fogging air and fuel everywhere in the runner and the EFI injector fuel strategy just adds more fuel to the mix. The precision timing of the injector really does
noting at the point that the fogger comes into action.

Tom V.

 

Still need to add the bungs but we have made great progress.

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AGREE A very nice manifold design (using again the GOOD Holley Upper plenum roof).

Tom V.

 

Its got cool factor too.

 

Thank guys! We added the injector bungs and I used a 14mm laser to aim the bungs before welding, it worked perfectly. I made a little target on the plexiglass to mark the spot. I also added the burst discs, that was a great suggestion.

I will be adding the nitrous bungs to the bottom of the runner like you guys suggested.

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THAT V-6 INTAKE IS GOING TO BE VERY NICE.

Keep up the great work.

Tom V.

 

I need a towel

 

Hi all, new to this forum, thought it was about time i joined up (even though im the wrong side of the planet) after having so many great reads here, makes a big change to actually have a forum where most threads stay on topic and most posts are relevant and conducive!

I hope its not a problem posting here but it seems relevant to me at least

I have a dilemma with designing an intake due to packaging constraints, its for a twin turbo Duratec 3.0 V6, i really want to achieve uniform cylinder filling and my solution thus far is this;

https://www.theturboforums.com/attachment.php?attachmentid=671790
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https://www.theturboforums.com/attachment.php?attachmentid=671791
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https://www.theturboforums.com/attachment.php?attachmentid=671792
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I have taken design ques from Porsche with the theory as discussed previously of the throttle body being "de-coupled" and the inlet hitting a wall / being divided and having time to calm down before reaching the runners.

From my crude drawing you can see one of the issues is that the ports are offset, i have offset the TB also to provide equal distance and volume to either plenum.
I aim to have a manifold volum of 160-180% as anything less i think will be difficult to acheive due to the distance between runners and TB.
Do you think i will need to run a balance pipe between the plenum ends?
Please ignore the plenums themselves otherwise for the minute

Really look forward to your input guys!

Dave

 

Your 3.0L Duratec design looks fine.
I can see why you felt you needed to bias the throttle body slightly to make the volume before the runners about the same.

You have the Porsche intake on the bottom, you have the drawing on the top.

Is the center picture your manifold or just another example? The link appears to imply modified Porsche.

Tom V.

 

Thanks for the comments, im happy with the TB bias and splitter then.

Yes the centre pic is a modified Porsche intake, i was just trying to describe the 'Y' split using that image as i looks like a nicer transition than the bottom pic 'T'

Id be interested to here your thought on the plenums, i cant make them overly large as the over all volume of the intake is going to get excessive i feel; im leaning towards 'RED / B' plenum design so there is more of a depth for the air to turn through 90 deg as it enters the runners whilst not wasting volume to the sides of runners (above and below on plenum 'A')

Designs are coming out with volme in the 175-210% hence trying to keep the plenums to a minimum.

https://www.theturboforums.com/attachment.php?attachmentid=671822
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https://www.theturboforums.com/attachment.php?attachmentid=671821
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One thing im definately unsure of is wether or not having a tapered plenum is beneficial, the way i see it (contrary to my first thoughts) the first runners are the hardest to feed whilst the end runners seem to always get the full fill, so is a tapered plenum goin to help 'starve' the end runners effectively boosting the first runners?

Dave

 

Unfortunately the air will always want to pack up in the back runners due to the speed of the air in the passage unless you can kill that velocity by having the air slam into a wall.
Other threads have discussed that strategy. Your Pyramid shape device at the inlet would just have the air doing a high speed "s" turn and most of the velocity would remain, therefore more air in the rear runners. Banging into walls and expansions after passage shapes tend to help things. Nice thing about just moving air is you can kill velocity without having fuel drop out of the mix.

Tom V.

 

So potentially it is better to have the split after the TB as a flat 'T' rather than a pyramid to kill velocity.

To that end would it be beneficial to run smaller ID pipe from the TB to plenums to reduce volume, thereby freeing up volume to be used in the plenums so the air can enter into a larger space again killing velocity? Or would that be pointless as the smaller ID pipe would naturally increase velocity??

I dont follow you when you say "Nice thing about just moving air is you can kill velocity without having fuel drop out of the mix. "

Dave

 

Reducing the diameter after the throttle body would not really do much before the flat wall impact you want.
A shape like this also helps with better distribution. https://mulpix.com/post/1407426932508741535.html as it has a nice radius before the 1st runner entry
and a decent volume and some depth before the back wall.

Tom V.