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What is the difference in performance between plumb back and atmospheric valves?

Remix-

By Remix-,
in Forced Induction Performance

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Roy Grand Master

Roy

Posted
Posted
Sorry Otto,  

Your wrong! no explanation needed.

Actually he is kinda right, on paper the inlet air will be cooled (to an extent), its just that in brush strokes the compression process heats far more then the expansion of the air from the BOV being plumbed back. :D

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Splitpin Newbie

Splitpin

Posted
Posted

Well I'm aircraft avionics tech and otto does have a point, but the 747 ACM system runs off about 150 deg 40psi bleed air and has had a heap more money spent on it than any turbo set up we'll ever see. The low pressures, low temps, and low flow rates of a turbo (compaired to an aircraft ACM) all add up to the cooling effect of plumbing back your BOV being nothing.

I'm looking at buying an r32 GT-R sometime soon and I'm thinking about using a trick that the Toyota Celica GT4 had on it called an anti lag valve. Instead of plumbing the air from the BOV back into the compressor side of the turbo I'm going to try directing it into the exhaust manifold on an angle so it gets directed straight at the turbine. This way the turbo should keep spining between gear changes. Now the only problem I can see is that maybe the hot/cold shock of the air on the turbine may cause it to shatter but thats just a minor detail :rofl:

If anyone can see and huge problems with what i want to do then please speak up. I'm more into electrical stuff so there may be something huge thats gonna throw a spanner in my idea.

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4door_Sleeper Veteran

4door_Sleeper

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Posted

How about this for an anti lag device, its called an AUTOMATIC TRANSMISION since I don’t need to take my foot off the accelerator between gear changes, I don’t suffer the lag problems of those lesser MANUAL TRANSMISSIONS. In fact the only time my BOV works is when I decelerate. (OK an auto isn’t much cop for track work, but for most other applications it’s the bomb)

But just to add to the comments above: the frictional effect of air moving through the system should be negligible as air moves in a lambda flow if I am not mistaken, and hence reduces friction by moving slower against the edges than it will in the middle (think of a river flowing down a riverbank, the current is strongest in the middle)

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