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Custom intake manifold - bad design?

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So I did order a custom intake manifold from a reputable welder that does these things for a long time.

I simply can not understand why the throttle body is so close to the 1st cylinder and why would you make such long runners.

Doesn't it mean that the cylinders will fill unequally? This was built for a GTX35 turbo, so definitely ram-effect is more important than low end torque.

Also, I had a fire incident which is unfortunate, although my manifold has been restored, I had a chance to actually have a look inside it :).

Do you consider this to be a correct runner shape? I am afraid this affects (negatively) the airflow especially at gear shifts, when TB closes and a lot of air has to enter the cylinders again, but since the design of the runner makes me unsure about this.

Thank you

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It's a tough one to really give you solid feedback on. Personally I would like to see a little more distance between the trumpets and the far side of the plenum wall. The location of the throttle body is probably not where I'd have put it but I've often been surprised at how well a manifold works that on face value looks like it would favour flow to one cylinder.

Theres a lot of science that goes into the design of an inlet manifold but beyond that you'd really need to be able to build and test multiple versions of a manifold design to really validate which is best. Most of the companies specialising in this work use CFD to speed up the design and validation.

Thanks Andre,

I guess my first step to assess on what is really going on in the combustion chamber is to pull the spark plugs and see what I get. 5 EGTs or lambdas are not the things I can afford, unfortunately, although it would reflect perfectly what is going on inside the cylinders.

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