Join Date: Dec 2008
Location: Tyler, TX
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The turbo is the most efficient form of forced induction short of the Axial Flow Supercharger (ala Jet engine). You get the most FLOW for a given HP input and the least increase in air temp.
At best, a turbo is about 72% efficient, that is very far from "free" power but much better than the 50% efficiency of a Roots/hEaton style blower.
Blowers will give you the great off-idle Tq like a N/A engine can, but cannot supply the coolish air at the upper RPMs like a turbo (or AFSC).
It's all about the goals. That is why the 6.0L/6.4L have VGTs, it allows a medium-large turbo to flow a lot of air at low enigne RPMs (like a small turbo), but not over-speed at the higher RPMs like a small turbo and still flow the amount of air that is needed to make very good power.
'93 F-250 HD, 7.3L IDI, 5spd - FARM TRUCK
I Support: Trailer brakes an every axle over the towing vehicle's GVW; CDLs for RVers; Safety inspections for ALL vehicles and 6 axle trucks (97K GVW proposal).
Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote - Benjamin Franklin
I vote for LIBERTY!