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Raceboy Raceboy is offline
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Join Date: Jun 2009
Location: Estonia, Europe
Posts: 1,198
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Quote:
Originally Posted by RarlyL8 View Post
Street turbos spend little time on boost which is where a properly sized tuned system helps out. There is also a bump in HP at the top end as the organized pulses hit the turbine in order.
This only applies to single-entry turbine. Twin scroll turbines with properly split (1+4 and 2+3 on 4cyl, 1+2+3 and 4+5+6 on 6cyl) exhaust manifold will neglect the necessity for making long tube headers. Thus, with twin-scroll turbine you get the best of worlds: short headers for fast spoolup+compactness without having to sacrifice top end.
Tube sizing is important as I said it already in my last post because the slower exhaust gases flow the more heat they lose -> less energy for turbine.
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'83 924 (2.6 16v Turbo, 530hp),'67 911 hot-rod /2.4S, '78 924 Carrera GT project (2.0 turbo 340 hp), '84 928 S 4.7 Euro (VEMS PnP, 332 HP), '90 944 S2 Cabriolet
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Old 06-10-2012, 12:42 AM
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