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Old 01-14-2010, 11:15 PM
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Can someone take the time to explain Boost, both via a Supercharger and Turbo. My understanding which is very neanderthal, it's the amount of air being pushed into the cylinder. But I'm a little confused in that I've seen "boost" switches to increase or decrease the amount. Wouldn't the fuel amount need to be adjusted too? Or is that done via ECM?

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Old 01-15-2010, 12:17 AM
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You could ask a number of members on here to help further your knowledge. Brad Zastrow, Hot Pursuit, 40FlatDeck, many helpful members in the community
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Old 01-15-2010, 02:18 AM
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I have never seen a "boost" switch
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Old 01-15-2010, 04:13 AM
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Dont know if this helps but I will throw what little I know in here:
Boost is the measurement of resistance to airflow not the actual amount of air being "pushed". The harder it is to push thru the resistance the higher the boost reading.

Example: A blower that makes 10lbs of boost on a stock
motor with stock components will make probably only about 5lbs of boost if you put big heads,cam,intake and exhaust on the same setup because you have lowered the resistance to air flowing thru the entire engine.

another example: 5lbs of boost on a 502 big blocks requires almost twice as much air to be "pushed" than 5lbs of boost on a 350..
Take a turbo rated at 20lbs of boost off a a small engine like a 4cyl Import sportcar and put it on a 600" V8 and it may not even make boost because the engine requires more air than the unit can push.
CFM is a much better qualifier for a supercharger than boost.
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Old 01-15-2010, 09:13 AM
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Quote:
Originally Posted by Griff View Post
I have never seen a "boost" switch
I use one.
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Old 01-15-2010, 09:39 AM
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Old 01-15-2010, 01:27 PM
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Quote:
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I use one.
So how does it work???????? I would guess some type of wastegate or pop off valve to relieve the extra boost????????
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Old 01-15-2010, 01:54 PM
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Quote:
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So how does it work???????? I would guess some type of wastegate or pop off valve to relieve the extra boost????????
As far as I can tell Check 300 has the ECM pre-programed for differnent boost levels that are controled by how fast he is spinning the huffer via different pulley sizes. But thats just a guess ???
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Old 01-15-2010, 02:06 PM
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As far as I can tell Check 300 has the ECM pre-programed for differnent boost levels that are controled by how fast he is spinning the huffer via different pulley sizes. But thats just a guess ???
Not quite, thats likely a turbo app.

His deal is always making more boost than he is using, and the excess boost is electronically "bled" off.

This way you can regulate output, and adjust for fuel quality, and make a decisions between output level and component lifespan.

Mercs 6 and 700's bleed off more than they use as well but from a supercharged app. this is why they can deliver their rated (long story) power at any altitude or under any load condition.

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Old 01-15-2010, 02:10 PM
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He does have a turbo set-up .That sounds more realistic ...Thanks Uncle dave
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