Not an I-4, a Pontiac 482 CID Twin Turbo Engine, some friends of mine made 2885 Horsepower. Same Pontiac guys who build "Big Chief's Pontiac Engines.

Tom V.

 

Easier to believe, as anyone with the coin can build a big block Chev with all aftermarket parts and get 3000 HP. Any 4340 crank, any 4340 rods, any forged pistons, any displacement, any cnc heads over 350 cc intake ports, any solid roller cam, and a quartet of 88 mm turbos will suffice. The only problem is the cost, and then a suitable transmission, which doesnt exist, so double the cost.

But you get a bit more respect, like Big Chief has, by doing it with a Traditional Pontiac Engine and a 350 cfm head, not a (350cc head).

Tom V.

 

cast off the shelf edelbrock tunnel ram manifold, un touched
cast out the box dart 325cc pro1 water heads, un touched

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sbc
stack injection manifold , converted to turbo

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Butler

I heard them heads where worked over. Damn!
3.99 baby!

 

I have a distribution issue on my Ford 4.6 2V motor using an Eddy Vic Jr and a 6061 elbow with a 90mm Accufab TB and this thread got me thinking into how to even the distribution among the cylinders. Since I love to design things I thought I would come up with an idea and get peoples input on it.
Car will be going for 900hp at boost levels from 25-35psi at 6500rpm.

Most of the designs I see dump all the air into a single "formed" chamber that tries to even the air above each intake stack. I was curious if using multiple "levels" with strategically placed holes to the next lower level may help distribute the air better..?

The below CAD pics were done real quick in the middle of the night so they only show my theory of the different chambers and hole placements. The distance between levels, hole shapes, hole sizes etc could be altered as needed if this theory would work.

ks

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Don't need the two layers with the holes before the stacks.

The air (hitting the flat wall) will evenly disperse just fine to the stacks without them.

Notice the center inlet and the flat wall on the far plenum side

Tom V.

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I didn't know if the spacing of the stacks being farther apart on a 4.6 2V would still distribute the air to the ends well enough.

Thank you!

KS

 

I am NOT saying use that manifold or modify that manifold for the 4.6L Engine.

I am saying that a manifold of that basic design pictured would work well for air distribution.

So post up what you are trying to do with the 4.6L Ford Engine.

Tom V.

 

I know, no worries..

ks

 

Hi Tom, first of all I just want to say thanks for all your help here. There's very little information out there and most of it exists in this thread! I've actually read it completely 2xs and took notes.

I have a project that you should be very well qualified to give advice and I'm hoping you will help. I have a 2010 mustang that I did a 3.5 ecoboost swap using the f150 PCM and 6r80 transmission. It's a drag car and currently holds the record for fastest 3.5 ecoboost, this was on the stock engine, stock turbos, e85 and a little help from a 75 shot of nitrous. I was only able to make 3 passes before breaking a piston skirt but ran 11.38 at 122mph leaving off idle, no boost. I had transbrake issues, long story. I was able to run e85 by installing injectors on top of the factory ecoboost intake and using a secondary fuel controller.

Fast forward to today, the engine is being built with diamond pistons, Manley turbo tuff rods, ported heads, larger valves, modified cams and new precision top-mounted turbos. We are shooting for 800-1000 whp. I also need to upgrade my intake manifold for a couple reasons, I want aluminum in case of a nitrous backfire, I need better positioned injector bungs, and I need better flow. I have a mechanical engineer friend that's helping me with the design, the engine builder is helping me weld it all up.

We have a design that I should be able to post a drawing of on Wednesday, I'm hoping you can analyze it for me. I found 3.7 runners for sale that I was planning on starting with, they seemed much better than what I could build myself. I'll need to weld on bungs which I would do somewhere in the middle of the runner. Overall the runners would be close to 10" including the velocity stacks that will be inside the plenum. I was planing on making a plenum 1.5x the engine displacement, the plenum space would be 5.5L.

More info to come, here's my old intake and the runners I purchased to build the intake. These runners were designed for ITB, I will not be using that. My plan was to use a gt500 throttle body.

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Manifold parts

I found this plenum top and base mounting flange from Holley. We will probably use this along with the runners I found for the 3.7. That leaves us with designing and fabricating the lower plenum only.

These parts may help someone else trying to build a custom manifold, they are fairly inexpensive. Also here's a cad drawing of the entire manifold, again I'll only be using the top plenum and buying the mounting flange for the lower. It's awesome that Holley sells these separately.

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Excellent Find!

ks

 

Thanks! I was surprised to come across it today after researching this for nearly a year.

 

We aren't done designing yet but here's a sketch of the bottom plenum. We will be using 2" injector bungs to reach the face if the velocity stack. This plenum volume is around 4x displacement with the top so we will be trimming that back by making the bottom center come to a point instead of flat between the runners. I'm not too concerned about large plenum volume, the 3.5 ecoboost daytona race car has huge intake plenums.

The Holley intake flange and plenum would go on top, these are the cast 3.7 runners from jenvy. Also I should a pic of the huge plenums on the rough Yates 3.5 ecoboost.

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Hate to screw up your design work but we tried that deal on a Pontiac Engine quite a few years ago. Did not work well at all.
HP was 2885 HP, to give you an idea of the capability of the engine (after team went to a different injector placement design (basically put the injectors back in the runners).

What was happening was the injector shields were blocking some of the airflow trying to get into the runner inlets and the fuel from the injector space before the runner inlets was also being forced to the rear of the plenum making those runners run fuel rich.

Tom V.

By the way, the people who assembled this engine (Butler Performance) also do the engine work on Justin's Crow Mod (Street Outlaws) race engine.
There are lots of good engine builders out there. I am posting the Pic based on your question about Intake design not as a Ad. They tried it, it did not work.

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Please screw it up, that's why I posted this here

Thanks for the input, we have a plan B that we were discussing this weekend that would allow us to move the injector in to the runner. I'll discuss this with the engineer and see what we can come up with and post another drawing. Thanks for getting back to me.

 

Ok here is the redesign. Much smaller plenum space, this will be around 1x engine displacement. What do you think about this?

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Very nice CAD work. I would think about your injector discharge position.
This is my first impression. The injector fires, the spray goes thru the center of the of the runner at the bolt together flange location, then it bangs off of the roof of the port about 2" after the bolt together flange. So now you have a lot of fuel on the roof of the port at that location. I would instead have the injector spray hit more in the center of the runner at the horizontal flange location. This gives the runner a nice "cone" of spray centered on the runner diameter at that point before the fuel and air go into the head.

Tom V.

 

I can't take credit for the CAD work, that's all from a friend of mine. Thanks though!

Thanks for the advice, I completely agree about the injector angle and we made that change. It looks like I'm ordering material tomorrow and we are getting started soon! I'll post a pic of the finished manifold in a couple weeks.

I found a 14mm OD laser (same OD as my injector) that I'll use to align the bung perfectly. I'll use the laser as if it's an injector and install it in the bung. I'll angle the bung until the laser fires in the exact center of the runner at the bottom, then I'll weld the bung in place.

Also, on your advice in previous posts, we plan to have the throttle body installed after a 90 degree elbow. Coming out of top plenum will be a 4" 90 and the TB will be bolted to the end. We are doing this assuming the air will be better mixed when it enters the plenum, not being affected by the TB blade.

If you have any additional comments on these ideas please let me know.

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