Turbo vs blower
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Michael
#56
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I can't think of any reason why a turbo engine would last any longer than a supercharged engine, unless the supercharged engines don't have intercoolers, and/or they are running high boost with an inefficient supercharger (more parasitic drag). The engine's intake ports have no idea where the boosted air is coming from.
Michael
Michael
Blower is just slaming air into the intake side, with no resistance on the exhaust side. So you have a lot more volital atmosphere. Kinda like your valve train etc. is getting continually ***** slapped............LOL. Causing a quicker failure rate.
Turbo's have been around a long time as so many have pointed out. One there is more to understand, but two you were married to them in the carburetor world. Now that fuel injection and programable fuel maps etc. are off the shelf items, it opened up a whole new animal in the performance world and seem to be comming on strong in all performance arena's
Again just going off memory here.............
Jon
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The reason a turbo engine goes longer between rebuilds than a comparable engine with a blower is the crankshaft on a blower application has the blower belt pulling on it and the bearings wear faster.
#58
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Don't forget the HP it takes to spin the blower! Try and rotate a roots and screw blower by hand, feel the resistance? On a 1000hp engine, the supercharger will probably take around 250-300hp. Atleast in the mustang world that was the rule of thumb. So, your 1000hp engine is making 1250 or 1300 or more.
With a turbo, it takes away very little hp, so a 1000hp engine makes only a little over 1000hp. These numbers aren't right on, but the difference is significant and why turbos are gentler on an engine.
With a turbo, it takes away very little hp, so a 1000hp engine makes only a little over 1000hp. These numbers aren't right on, but the difference is significant and why turbos are gentler on an engine.
#59
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Turbo makes more power with less boost.
A turbo dosent require radical cam specks..low duration and overlap. Low valve train stress.
At least on a car (boats a bit different) once a steady state speed is reached the turbo is just idling along not producing much boost and not soaking up much energy or stress on the engine.
Turbo's are or can be one of the most efficent devices there is at one time only a transformer was more efficent.
A turbo dosent require radical cam specks..low duration and overlap. Low valve train stress.
At least on a car (boats a bit different) once a steady state speed is reached the turbo is just idling along not producing much boost and not soaking up much energy or stress on the engine.
Turbo's are or can be one of the most efficent devices there is at one time only a transformer was more efficent.
#60
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DonziJapan - I don't see what difference it makes what the output curve looks like, and which blower are we talking about, centrifugal or positive displacement?
courgarman - Don't see what difference it makes if the boost pressure is higher than the exhaust pressure. Neither type of engine uses much overlap anyway. Also a well designed turbo system also has higher boost pressure than exhaust pressure.
check300 - I can see on startup how the bearings could wear more with the blower belt, but if you've broken through the oil film while running, the bearing would get so hot it would seize.
Joe92GT - Agree the blower engine will need more overall horsepower output since some of it is going into driving the blower, and could reduce the life.
turbo2256b - Blower engines don't have radical cams either, or it will blow the fuel out the exhaust during overlap. Agree, more parasitic loss with the blower engine.
If you run any engine under boost, the life is going down. It's like running at full throttle and then some.
Michael
courgarman - Don't see what difference it makes if the boost pressure is higher than the exhaust pressure. Neither type of engine uses much overlap anyway. Also a well designed turbo system also has higher boost pressure than exhaust pressure.
check300 - I can see on startup how the bearings could wear more with the blower belt, but if you've broken through the oil film while running, the bearing would get so hot it would seize.
Joe92GT - Agree the blower engine will need more overall horsepower output since some of it is going into driving the blower, and could reduce the life.
turbo2256b - Blower engines don't have radical cams either, or it will blow the fuel out the exhaust during overlap. Agree, more parasitic loss with the blower engine.
If you run any engine under boost, the life is going down. It's like running at full throttle and then some.
Michael