Its actually been done before, i seen a couple videos on youtube if i could remember them i would post them up...

 

Heres the videos he uses a 05 lly turbo i guess, and does twin turbos on a 6.5

 

What needs to be done to make the switch to the Holset HX40 and can anyone tell me how much boost a 6.5 can handle .

 

Bolts up to the stock flange, might need to clock the compressor and turbine housings, oil supply and drain then a new downpipe, i think that can hold 15 dont count on me for that tho

 

depends on the engine and equally as much on the turbo.

Low back pressure turbos can safely make more boost and the strength left in the engine is always an unknown,the holset will safely make more boost than the GM turbo but the tune in the ECM also is a contributing factor as far as throwing codes.

A stock ECM will code after sustained boost above 10 psi-a tuned ECM will solve that.

 

Thanks Guys , may just try that & see if that will improve my mileage , have already boosted it by about 1/3 just by put 4" straight pipe from downpipe back . Must say she sounds Mean& Narsty now.