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Turbo vs blower

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Old 11-26-2007, 10:51 PM
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The new adjustible inducer and exducers should take turbos way beyond any blowers as soon as they make them work.
Should be very little lag and alot of power.
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Old 11-26-2007, 10:56 PM
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Originally Posted by Bigyellowcat View Post
23' headed conventional engine around 750 hp reliable
SB2 headed conventional engine around 900 hp reliable
LS1 style engine around 1000 hp reliable

which one do you want?
What do they usually run $ ? I was thinking more like 500hp, those are big numbers.
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Old 11-26-2007, 11:08 PM
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Originally Posted by TexomaPowerboater View Post
What do they usually run $ ? I was thinking more like 500hp, those are big numbers.
if you only want 500 hp I would not waste the money doing a turbo set up you can easily get that naturally aspirated with SB2 cylinder head.
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Old 11-26-2007, 11:16 PM
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if you only want 500 hp I would not waste the money doing a turbo set up you can easily get that naturally aspirated with SB2 cylinder head.
You can get 500 with a off the shelf AFR head.
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Old 11-28-2007, 02:19 AM
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In answer to the original question, turbos are easier on parts than blowers. I have been running twin turbo engine configurations for over 10 years and consistently get more time between rebuilds than my blower loving friends.
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.

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Old 11-28-2007, 06:48 AM
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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
Seems at one point I was told one of the big life savers with Turbo's is balanced pressure. Turbo is pushing air in the intake side of the engine, but the exhaust side is pushing air into the turbo's so you have equal resistance on both side's providing harmony.

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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Old 11-28-2007, 09:39 AM
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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.
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Old 11-28-2007, 11:18 AM
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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.
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Old 11-28-2007, 12:59 PM
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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.
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Old 11-28-2007, 02:34 PM
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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
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