You could consider getting Turbo Dynamics to hybrid modify your VNT17
http://www.turbodynamics.co.uk/
Garrett Turbochargers ? Part No 721021-0004 ? Aircooled
VW Part No. ?038253016G - 1999->
APLICATION : VW GOLF 1.9 TDI - 150BHP
Stage 1 ? MD374
Hi flow GT17 compressor wheel, cnc machined compressor housing, 360 degree thrust bearing, cut back turbine blades, lightening of turbine wheel for faster ?spool up?, modified V.N.T. turbine housing, uprated turbine seals. Other ?blueprinting? modifications. APPROX 200 - 220 BHP
Stage 2 ? MD376
Hi flow 2275 spec compressor wheel, cnc machined compressor housing, 360 degree thrust bearing, cut back turbine blades, lightening of turbine wheel for faster ?spool up?, modified V.N.T. turbine housing, uprated turbine seals. Other ?blueprinting? modifications. APPROX 240-260 BHP
Stage 1 ?925 plus VAT for new unit
Stage 2 ?975 plus VAT for new unit
Price to rework existing unit is around ?350 dependent on condition.
I am giving this serious consideration. I take the indicated power figures with a pinch of salt for an otherwise standard remapped engine. The weakness of the standard turbo is the bearing/spindle over 200bhp so this seems like the answer for the next phase of power. If it delivered, I would then investigate running higher boost and fuelling (using standard injectors). I too considered the VNT-20 but think space considerations and lag may rule it out.
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