intake manifold modification

[OldMav]

The petrol manifolds do not fit.
And yes I did test a round lid makes no difference as this is not a true plenum as such. And I have built and tested many designs but most near all were for 200rwkw in mind.
I have not done any testing to improve vacuum for the N/A engine. But if you emulated the square to tube runners and about 130mm tube runner length and about half the engines capacity for the volume of the plenum you would probable produce a stronger torque curve. But you may not realise for a 2000rpm cam sweet spot it is very difficult to get a N/A diesel to react to this sort of thing like a petrol does. Your gains are usually about half of what you would expect compared to a petrol. hence turbo best bang for your buck.
As for reliable well this engine is a freak and was designed with little compromise for strength. There are many of these engines with double and triple the std power doing way past I million KLMs treated correctly.

This is the design I am runner at the present.

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