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jtmarten
08-23-2008, 01:46 PM
I have a question about which type of vacuum is best. If I source it right to the intake, it has a huge amount of vac at idle. If I source it to the air box it would have low vac at idle, higher at higher rpm.
Which is better if only using a single output?

ridelong
08-23-2008, 05:02 PM
jtmarten,

If you want only to have the maximum vacuum possible, go to the intake manifold. People think there is more vacuum upstream of the butterfly under wide open throttle (WOT). If you think about it, that's impossible. The source of the vacuum IS the intake manifold. How could the thing using the source achieve more vacuum than the source? (putting my soapbox away now)

Does it get better gas milage? I have my best increase so far inputting it upstream of the butterfly 37%. 28% is best so far into intake manifold. But the intake keeps the electrolyte hugely cooler, and it generates much better when the electrolyte is warm. So I jacked my amps from 5-6 to 8.5-9.5, haven't got results yet. Got some numbers, but no conclusions yet.