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Hi lads, I've got the 7 blade gt3076 with the t04s 0.7 a/r compressor cover on it, 0.82A/r rear housing ext gated. I have used this turbo on my previous RB25DET and made 292rwkw @18psi on the state's lowest reading dyno (C-Red @ W.A). I'm currently doing a RB30DET conversion with this same turbo and after lot of research (sau, hardtune, nasioc etc) I find that there is not a conclusive answer to the difference between the real GT3076R (6 blade) vs the Gt3076 with 7 blade T04S compressor cover on it beside "the 7 blade old design chokes flow at high boost, it acts like a brake". I have looked the compressor maps (attached below) and there isn't much variation point to point between the pressure ratio and the air flow between the 6 blade and 7 blade, they also flow to about 53lb/min at 68% efficiency. Question is, can experts point out where I did wrong/right to verify the 7 blade (52T) is inferior to the real 6 blade gt3076r (56T)? What I'm aiming is like al's or cubes setup but externally gated, ~350rwkw with E42.5 (50% E85 and 50% 98 ron) with the intention of full boost by 3000rpm and to max out the AFM, turbo and injectors. The setup is: RB30DET 9:1 CR 86.5mm CP pistons Spool conrod My current 7 blade turbo Tomei poncams RB25DET head vct enabled Power FC Steam pipe exhaust manifold Greddy Intake manifold 760cc JECS Injectors Z32 AFM The RB25 made full boost by 4000rpm which was great for barbagallo long track but as soon as I go short track or enter rally sprint events (very tight course) the lag really slowed me down. Also did a quick calc based on the real GT3076R RB30DET setup like al's and cubes; 3L, 7000rpm, VE 92%, Boost: 18psi gives a pressure ratio of 2.2 and 53lb/min air flow (see no corrections air temp etc are made here) plots to the right side of the 65% efficiency range but these guys are making ~330rwkw happy power..... What do you think?