Variable Twin Scroll Turbo on a diesel, opinions please from turbo guru's

[quirkyturtle]

If you are interested in understanding how the twin-scroll system works have a look at this link: https://www.mhi.co.jp/technology/review/pdf/e501/e501023.pdf , it is very important the firing order of 1,3,5 and 2,4,6 are grouped, and the firing order of a 12-ht is 1-4-2-6-3-5, which is different from most inline 6 engines with 1-5, 3-4, 2-6, just check the corresponding ports are going to the correct place. For a 12-HT, cylinders 1,5,6 need to be matched and 2,3,4 also, unlike most with 1,2,3 and 4,5,6. I am currently producing a stainless equal length twin-scroll manifold for my 12-HT 60 series and if all goes well I could look at making a few if others were interested.

 

[Nz Nath]

On a 1-4-2-6-3-5 firing order you'd still want to group 123 and 456... You're trying to seperate cylinders which are adjacent in the firing order.

 

[chelo]

I received my dual volute turbo and manifold to suit with an external wastegate. Should be quick spooling.

 

[Buds]

I received my dual volute turbo and manifold to suit with an external wastegate. Should be quick spooling.

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This is the Eclipse over under dual volute. I been waiting to see how these perform, have you got it on and tuned yet?

 

[chelo]

This is the Eclipse over under dual volute. I been waiting to see how these perform, have you got it on and tuned yet?

This is the eclipse dual volute. I'm waiting on my injectors to come back. It should be another week before I get them. Once I get them and a few other items from partsouq, I will install it.

 

[quirkyturtle]

If it isn't quick enough spooling you should look into using a quick spool valve, which diverts the gasses on one scroll to go thru the other, which means for the gas to pass thru the smaller volume it has to increase in speed which in turn spools the turbine faster, then at higher boost levels the valve opens allowing for the full flow of both scrolls, kinda like a variable geometry turbo but much cheaper and less moving parts.