High mount ?

 

That boost6 looks more suited to Petrol

 

Genuine. About $300 delivered from partsouq

 

Maybe for one half. $231 and $292 plus delivery. around $550

 

Dts

 

Highmount or lowmount does not bother me.

Is the genuine or Denco unit really much of an upgrade over the safari manifold I already have?

 

Nothing really wrong with the safari manifold.
Factory or denco are good as well.
Yes Radius has a new manifold design with a better collector setup, improvements in spool times over the previous design. Richie was sending me one to do some testing with, but he is working on another now with a different collector again.
But piston cracks? where are they? If the are on the outer edge near the pre comb opening, or around the edges of the piston chamber itself, little tiny cracks from the edge of the sharp edges, they are quite common to see ,but usually after a few km though.
I does sound like you just have multiple issue though.

 

Oh and Radius will also have a similar collector style factory position manifold soon.

 

I cannot tell you what is best. What I can tell you is long runners with collector are more suited to higher rpm torque so what you gain you loose at the other end.

I haven't seen a radius example in the flesh but there is a bit more to it than sticking pipes together. I have made both and tested them, I even made my own cast manifold because none were made yet at the time that were of a STD I thought good.

If you do your research here you will find info regarding what is required for a std turbo manifold to work to its optimum for a 2000 rpm ish torque peak to complement our cam shaft for a street TD42.

To answer your question Your safari manifold will work to its best with a bit of die grinding at the port intersection. For your application towing heavy loads your log Safari cast manifold is ideal so no the two other examples are not an upgrade over your existing manifold.

If you want to play with pulse then what you have is ideal if you do a twin scroll turbine. Are the gains significant, No because a diesel works at low rpm to generate its torque from fuel injected to develop gas to drive the turbine wheel early in the rpm range.

I really don't know your issues but I can tell you the manifold doesn't have much to do with back pressure or getting the gas away. For our diesel we will see high ratios imp to emp 1.4 is about the limit you should see. And if you can find a turbo to see less than 1:1 then you have the ideal if you can still get the turbine drive to develop the power you expect.