Subaru Enthusiasts Car Club of the Sierras - View Single Post

knucklesplitter · 2007-12-20, 04:06 PM

I hate to argue the rotated intake manifold thing, especially with Mike advocating it... but how much IC tubing length does that save? What - 2 or 3 feet of 2.75"OD tubing? That's about 200 cubic inches (or about 1/8 cubic foot) of volume. How long does it take for a 400whp turbo to pressurize 1/8 of a cubic foot? That would be the gain in response. 400whp is say 500bhp which is about 500cfm or 8 cubic feet per second for a whopping 0.015 sec reduction in response just SWAGging it. I dunno - there must be something I don't understand. And running speed density (or BTM) there is not the lag time between MAF reading and induction into the cylinders either - that's the thing I don't like about FMIC and its long tubing along with draw-thru MAF.

2007-12-20, 04:06 PM	#29
knucklesplitter EJ205 Real Name: Matt Taylor Join Date: Jun 2005 Location: Cousin-Fck, Carolina Posts: 1,475 Wish in one hand and sht in the other...	I hate to argue the rotated intake manifold thing, especially with Mike advocating it... but how much IC tubing length does that save? What - 2 or 3 feet of 2.75"OD tubing? That's about 200 cubic inches (or about 1/8 cubic foot) of volume. How long does it take for a 400whp turbo to pressurize 1/8 of a cubic foot? That would be the gain in response. 400whp is say 500bhp which is about 500cfm or 8 cubic feet per second for a whopping 0.015 sec reduction in response just SWAGging it. I dunno - there must be something I don't understand. And running speed density (or BTM) there is not the lag time between MAF reading and induction into the cylinders either - that's the thing I don't like about FMIC and its long tubing along with draw-thru MAF.