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 2443TT
A.k.a.: Ian
Fahrvergnugen
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| posted on April 10th, 2003 at 05:17 PM |
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Vacuum Pumps - Performance applications
Has anyone ever considered using a vacuum pump on their high performance engine? It seems that a lot of more radically engineered engines are doing
this for some benefits in power and improved oiling.
There are few ways this is being done in VW's that I have read about. They are mechanical or electric pump, or by a velocity-extraction pipe
welded into the exhaust header (which only works at higher rpms).
From what Ive read there are quite a few advantages.
- Reduced oil leaks (good in vw's)
- Less pressure on the bottom of the pistons on the down strokes(less horsepower loss)
- Reduced oil foaming
any thoughts?
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Baja Wes
Bishop of Volkswagenism
V6 Baja Pioneer
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| posted on April 10th, 2003 at 09:37 PM |
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I can see it would reduce oil leaks, basically cos it is sucking up the blow by before it can make any crank case pressure.
I think it would increase oil consumption because it would suck out the oil/air mist before it had a chance to seperate out.
I woulda thought the HP increase would be almost unmeasurable.
I think it may help cooling as blow by is extremely hot and heats the oil. It is the reason older engines run hotter (more blowby heating the oil)
I would install a sand seal on the crank pulley before trying to run this set-up, otherwise you would suck crap in though the oil slinger threads.
That's my thoughts...
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70AutoStik
Insano Dub Head
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| posted on April 10th, 2003 at 10:06 PM |
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In High Performance applications they produce a significant increase in HP due to decrease in windage - a Group A engine will lose about 40HP without
it! I think for most applications on the beetle the drag of the pump (it's a crank-driven pump) would outweigh any benifits.
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OvalGlen
Custom Title Time!
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| posted on April 11th, 2003 at 11:58 PM |
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If I were doing it I would go for the scavenger in the exhaust after the collector system.
Just as the stinger or tail pipe expands after the collector.
Regards,Glenn>
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