sure quiet around here lately...........

kingcat162

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They are the same pressure....................
So many people think it's a 3-4psi boosted machine - - when it's actually a ZERO psi boosted machine - it's a 14.7psi in the manifold all the time machine - there is a huge difference between 14.7psi in the manifold and 17.7psi in the manifold
 

maxwell

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So many people think it's a 3-4psi boosted machine - - when it's actually a ZERO psi boosted machine - it's a 14.7psi in the manifold all the time machine - there is a huge difference between 14.7psi in the manifold and 17.7psi in the manifold


ok now your just confusing everyone. why do you feel that you need excess manifold pressure?

you can say its not boosted all you want, but compared to an N/A sled it has higher manifold pressure at 8000ft so?

and when you chop the throttle there is pressure releasing. Its just the way the computer manages the boost pressure. because when the throttle bodies close there is pressure there LOL

this is all part of why it runs so flawless. if you are maintaining 14.7 PSI manifold pressure at 8000ft you are 40hp above the N/A version
 
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kingcat162

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what's the manifold pressure on a na expert at 8000feet?

not 14.7?


oh so it does produce boost then....lol
It produces enough boost to compensate the loss in absolute manifold pressure - at 8000 ft you will lose around 4lbs of absolute manifold pressure to 10.7 - the ECU tells the system to maintain the 14.7 - if you put a boost gauge on it you will see zero all the time - all boost gauges are also calibrated to 14.7 - comprehenday?
 

minnow10

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thats genious IMO. The only head wrapping fact is that it flat out works. Doesnt really matter how BRP engineering arrived at the 40hp boost for most. why do you need boost pressure on components? sounds perfectly engineered.

WHOA WHOA WHOA , you want to start an argument, put the word "perfect" and "Engineer" in the same sentence!
 

kingcat162

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If it was pushing 4lbs of boost over and above 14.7 it would have an absolute manifold pressure of 18.7psi - it never will without a reflash - that's all I'm saying - as much as everyone's wonderful little ears are hearing the awesome turbo sounds - it's a zero boosted machine end of story it's a 14.7 absolute manifold pressure machine - everybody and their dog needs to wrap their head around that 1 - even tho they think it's awesome and it's pushing 4 lbs it's not pushing 4lbs over and above 14.7 - the bikeman tune might do that I'm not sure - but stock this is what it is - it is what it is bottom line
 

maxwell

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If it was pushing 4lbs of boost over and above 14.7 it would have an absolute manifold pressure of 18.7psi - it never will without a reflash - that's all I'm saying - as much as everyone's wonderful little ears are hearing the awesome turbo sounds - it's a zero boosted machine end of story it's a 14.7 absolute manifold pressure machine - everybody and their dog needs to wrap their head around that 1 - even tho they think it's awesome and it's pushing 4 lbs it's not pushing 4lbs over and above 14.7 - the bikeman tune might do that I'm not sure - but stock this is what it is - it is what it is bottom line


Ya your correct, But why does anyone need to wrap their head around that if it was 4lbs above 14.7 it would be 205hp at 8000ft which is not advertised. When the throttle bodies close there is 4psi to release LOL. so ya, it is boosted, altutude compensating, turbo normalized as they call it in the aviation industry. Makes 40 more hp at 8000ft and makes cool sounds no matter what scientific way you slice it.
 

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I think it’s quiet because some of us are waiting for a true game changer. The doo turbo is within 60 lbs of a sidewinder with a can. 50 lbs heavier than a stock poo 850. Love the engine but she’s a little heavy.
 

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It produces enough boost to compensate the loss in absolute manifold pressure - at 8000 ft you will lose around 4lbs of absolute manifold pressure to 10.7 - the ECU tells the system to maintain the 14.7 - if you put a boost gauge on it you will see zero all the time - all boost gauges are also calibrated to 14.7 - comprehenday?

oh I get it, just don't think you do
 

powpowpowpow

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I think it’s quiet because some of us are waiting for a true game changer. The doo turbo is within 60 lbs of a sidewinder with a can. 50 lbs heavier than a stock poo 850. Love the engine but she’s a little heavy.

When the doos start riding with t axys at 200hp+ its not going to be fun. More power and min 50lbs less weight
 

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Well for starters everyone needs to stop measuring absolute manifold pressure at altitude because a MAP sensor actually measures vacuum below absolute 14.7

what is the turbo for? increasing manifold pressure, one might even say for boost. or just for looks?
 

AreWeThereYet

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what is the turbo for? increasing manifold pressure, one might even say for boost. or just for looks?

When an engine load increases, it pulls more vacuum the MAP sensor tells the ecu hey more fuel/air,.. the turbo as was mentioned is an altitude compensator delivers more air to reach absolute 14.7,.. you could go as far as saying its a vacuum compensator. There is no boost per se as there is air makeup because of less density at altitude.
 

lilduke

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You & 90% of people don't get it - if you have a boosted machine with data logging capabilities - then and only then will you understand

lol I get what your are saying. it doesn't boost above 14.7...
 
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lilduke

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When an engine load increases, it pulls more vacuum the MAP sensor tells the ecu hey more fuel/air,.. the turbo as was mentioned is an altitude compensator delivers more air to reach absolute 14.7,.. you could go as far as saying its a vacuum compensator. There is no boost per se as there is air makeup because of less density at altitude.

so if air pressure is 11psi and its boosting it to 14.7 how is that not boost?? what ever
 
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maxwell

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so if air pressure is 11psi and it boosting it to 14.7 how is that not boost?? what ever

because there is no actual "boost" pressure in the airbox, only sea level calibrated pressure.

again, dont friggn matter what way you slice it the spinny thing forces air in to make it go faster
 

maxwell

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You & 90% of people don't get it - if you have a boosted machine with data logging capabilities - then and only then will you understand


i have a similar sled to yours, 12 psi, Full WTA, data loggers, fully built engine, EGT loggers, you name it. Runs phenomenal. i know more about turbos now after building that machine than i will ever care to know again.

It sat in the garage all year
 
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