Power used to spin a blower... Discussion ???
#21
12 Second Club
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I think the point that people are missing is this: If I had no discharge pipe on an F3 blower, and I was letting it push the air into the open atmosphere, then I could freespin the blower to max rpm with not much horsepower at all. For reference, Magnacharger says that it takes only 0.33 hp to freespin their blower at 1000rpm engine speed. I couldn't imagine it taking more 5 to freespin any blower to max rpm.
Now here is where the difference is, when a blower is hooked up to a system and boosting, for example, 20psi, that 20psi of pressure force is pushing in all directions. Thus, it is definitely pushing backwards onto the blower wheel and trying to slow it down/stop it. And that is where the difference comes. It's the pressure.
I have also heard the old story about, "The new 345hp Dodge hemi engine does not have enough horsepower to power the blower on a top fuel car. What they MEAN is that if the hemi engine were connected to a blower system that could still pressurize a seperate system, BUT not yield the benefits of the boost itself, then yes, it could not turn it to the same rpm. But obviously a certain blower engine is receiving the benefit of the boost level to create more power and thus has no problem turning over it's own blower.
Hope I made that easy to read.
Now here is where the difference is, when a blower is hooked up to a system and boosting, for example, 20psi, that 20psi of pressure force is pushing in all directions. Thus, it is definitely pushing backwards onto the blower wheel and trying to slow it down/stop it. And that is where the difference comes. It's the pressure.
I have also heard the old story about, "The new 345hp Dodge hemi engine does not have enough horsepower to power the blower on a top fuel car. What they MEAN is that if the hemi engine were connected to a blower system that could still pressurize a seperate system, BUT not yield the benefits of the boost itself, then yes, it could not turn it to the same rpm. But obviously a certain blower engine is receiving the benefit of the boost level to create more power and thus has no problem turning over it's own blower.
Hope I made that easy to read.
#22
Good point ^^^
I figured that the restricton on the blower forcing air in to the engine would be where the load on the engine comes in to play. My reference to the F1-A just blowing in to the air was ment more to get an idea of the power a engine would lose driving a blower that is loaded to the max.
I figured that the restricton on the blower forcing air in to the engine would be where the load on the engine comes in to play. My reference to the F1-A just blowing in to the air was ment more to get an idea of the power a engine would lose driving a blower that is loaded to the max.
#23
So would it also be safe to say that if a engine makes 500 hp (forced induction, driving its own blower) Now put a 200hp engine in the bed of the truck to drive the blower. Feed the engine the same amount of air as before, it would pick up 200hp not having to drive it's own blower ? So now the same engine makes 700hp. Hope that makes sense.
#24
Launching!
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I think this would be easy to do. Get a baseline of an engine on an engine dyno, then install the blower. Do not hook the discharge piping to the intake. Instead, outfit the discharge piping with a damper so you can regulate backpressure on the compessor outlet (simulating boost). It will take a bit of screwing around to get the backpressure right, but eventually you can dyno it again and compare it to the baseline numbers. This would give you a pretty good idea of how much it takes to spin it at a given boost. I guess you could also do this on a chassis dyno, but I could see the numbers not being as accurate.
#25
But whats the point in installing another engine when you already have a perfect engine that is more than powerful enough under the hood of the car that is more than capable of feeding itself with boost.
if it is simply to get instant at any RPM then this can be simiulated / engineered in MANY different ways. heel you would be better fitting batteries and an electric motor to the engine to give you the 'boost' you needed until the blower kicked in (hint hint this is what Maclaren are doing with their P1).
Alternatively, just fit a gearbox / clutch or converter that will get you in the power band. you want.
if it is simply to get instant at any RPM then this can be simiulated / engineered in MANY different ways. heel you would be better fitting batteries and an electric motor to the engine to give you the 'boost' you needed until the blower kicked in (hint hint this is what Maclaren are doing with their P1).
Alternatively, just fit a gearbox / clutch or converter that will get you in the power band. you want.
#26
But whats the point in installing another engine when you already have a perfect engine that is more than powerful enough under the hood of the car that is more than capable of feeding itself with boost.
if it is simply to get instant at any RPM then this can be simiulated / engineered in MANY different ways. heel you would be better fitting batteries and an electric motor to the engine to give you the 'boost' you needed until the blower kicked in (hint hint this is what Maclaren are doing with their P1).
Alternatively, just fit a gearbox / clutch or converter that will get you in the power band. you want.
if it is simply to get instant at any RPM then this can be simiulated / engineered in MANY different ways. heel you would be better fitting batteries and an electric motor to the engine to give you the 'boost' you needed until the blower kicked in (hint hint this is what Maclaren are doing with their P1).
Alternatively, just fit a gearbox / clutch or converter that will get you in the power band. you want.
#27
If you haven't already have a look at the turbine boosted engine. Look crazy but is all fast up the hill!
#28
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I think a 1000cc + bike engine would probably fit the bill better if someone wanted to try it (I would LOVE to read the build thread ). It would give you good rpm band, fast throttle response and light weight.
If you haven't already have a look at the turbine boosted engine. Look crazy but is all fast up the hill!
If you haven't already have a look at the turbine boosted engine. Look crazy but is all fast up the hill!
#29
I think a 1000cc + bike engine would probably fit the bill better if someone wanted to try it (I would LOVE to read the build thread ). It would give you good rpm band, fast throttle response and light weight.
If you haven't already have a look at the turbine boosted engine. Look crazy but is all fast up the hill!
If you haven't already have a look at the turbine boosted engine. Look crazy but is all fast up the hill!
#30
On The Tree
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I have used two superchargers in my automotive life. One was a B&M 144 on a small block. Wholly f*ck I'm glad those days are over. What a pile...
I have an Edelbrock E-Force on my 2009 Silverado. The Eaton rotor assembly is definitely tight and with the air its moving, I don't doubt it takes quite a bit of HP to get the thing moving. I recently switched to an 8lb pulley (plus a few other mods) and got 420hp to the rear wheels. With the 6lb I got 350hp. I really don't want to go much further than that with this truck. I have a feeling the transmission hates me.
I have an Edelbrock E-Force on my 2009 Silverado. The Eaton rotor assembly is definitely tight and with the air its moving, I don't doubt it takes quite a bit of HP to get the thing moving. I recently switched to an 8lb pulley (plus a few other mods) and got 420hp to the rear wheels. With the 6lb I got 350hp. I really don't want to go much further than that with this truck. I have a feeling the transmission hates me.
#31
UNDER PRESSURE MOD
iTrader: (19)
I think the point that people are missing is this: If I had no discharge pipe on an F3 blower, and I was letting it push the air into the open atmosphere, then I could freespin the blower to max rpm with not much horsepower at all. For reference, Magnacharger says that it takes only 0.33 hp to freespin their blower at 1000rpm engine speed. I couldn't imagine it taking more 5 to freespin any blower to max rpm.
Now here is where the difference is, when a blower is hooked up to a system and boosting, for example, 20psi, that 20psi of pressure force is pushing in all directions. Thus, it is definitely pushing backwards onto the blower wheel and trying to slow it down/stop it. And that is where the difference comes. It's the pressure.
I have also heard the old story about, "The new 345hp Dodge hemi engine does not have enough horsepower to power the blower on a top fuel car. What they MEAN is that if the hemi engine were connected to a blower system that could still pressurize a seperate system, BUT not yield the benefits of the boost itself, then yes, it could not turn it to the same rpm. But obviously a certain blower engine is receiving the benefit of the boost level to create more power and thus has no problem turning over it's own blower.
Hope I made that easy to read.
Now here is where the difference is, when a blower is hooked up to a system and boosting, for example, 20psi, that 20psi of pressure force is pushing in all directions. Thus, it is definitely pushing backwards onto the blower wheel and trying to slow it down/stop it. And that is where the difference comes. It's the pressure.
I have also heard the old story about, "The new 345hp Dodge hemi engine does not have enough horsepower to power the blower on a top fuel car. What they MEAN is that if the hemi engine were connected to a blower system that could still pressurize a seperate system, BUT not yield the benefits of the boost itself, then yes, it could not turn it to the same rpm. But obviously a certain blower engine is receiving the benefit of the boost level to create more power and thus has no problem turning over it's own blower.
Hope I made that easy to read.
#32
This is the exact reason why it is more efficient to put a bigger blower on a bigger motor. Spinning the blower to the same rpm, ie same pulley setup, it will take less power on a bigger cube motor making say 15psi, then a smaller motor spinning it the same rpm making 20psi.