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Discussion Starter · #1 · (Edited)
I have heard 2 different arguments...

1: The super is belt driven which means the engine has to word harder to make boost.

2: Because the super makes power at low rpm.. you can change gears at lower rpm's which helps the engine

Anyway, my question is with a forged rotating assembly... does the super cut away at engine life and reliability? I know it depends on how you drive it and how much power/boost you are making, but I'm just looking for a general answer. I had chosen to go turbo mainly because I thought supers were bad for the engine, but after reading http://www.superchargersonline.com I decided to reconsider. Usually if I talk to a turbo guy... he'll say go turbo, and if I talk to a super guy... he'll say go super. haha... super guy ANYWAY I just want a non-opinionated answer... just lay down the facts.

All input would be appreciated!

Alex

BTW: I'm sure that this topic has been discusses more than once... I just couldn't find anything that answered my question.
 

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This might be extreme, but try carrying a 200# ball around your leg all your life.

If it take XX amount of hp to make boost, I don't care what gearing you have, it takes work to turn that pully, and the more pullies you have the harder the engine has to work.
 

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Discussion Starter · #3 ·
but with forged internals would I see engine life/reliability drop?

Thanks for the input
 

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Turbos do not affect the engine life like a supercharger would. IMO if you were to compare a Turbo charged and Supercharged engine for engine longevity, the Turbocharged engine would wear less.

Turbos make more power in a boost to power comparison. Since turbos dont feed off of the engine, they are more efficient at making power.

However, superchargers are easier to install, make power at lower rpms, and are alot cheaper. If you want to increase boost, just change the pulley.
 

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Discussion Starter · #5 ·
I got some thinking and researching ahead of me...

anyone else have any input?

Thanks
 

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Turbo chargers do 'feed' off the engine....just in a different way. They use the exhaust pulses to turn the compressor wheel instead of the crank. This creates backpressure in the exhaust system. Back pressure is also drag on the engine. The more efficeintly you get rid of the exhaust the faster and more effectivly you can fill the cylinder w/ air/fuel mixture. This is why a good exhaust system is crucial on a turbo car. If you get alot of back pressure in the system the turbo will not spool up as quickly and not be able to pressurize the intake system as quickly -> "turbo lag".

W/ a good exhaust, you'll get less drag on the motor (in the form of back pressure) than you will w/ a crank driven compressor. So you'll be able to make more useable power at the same intake pressure (compared to a supercharger) due to the reduced "drag" on the motor. Also, since the turbo runs independantly of the crank, intake pressure does not have to be relative to the crank rpm. Meaning that you will be able to make more boost earlier and keep it throughout the rpm range, making more power under the curve as well. That depends on what kind of and how big a turbo you use though.

Hope this helps.

SJ
 

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Discussion Starter · #7 ·
Thanks for the info, I knew most of the ups and downs to turbos, but I never really thought about stress because of too much back pressure. I now just have to decide if I want to go super or turbo. If money wasn't an issue I'd say turbo all the way, but unfortunatly it is :( I plan on keeping my car for a long time... so I should probably stay away from forced induction anyway, but I'm like everyone else... I want more power :D

If I do get a turbo or blower and 6 years down the line my engine is worn out pretty badly... what does that mean? Do I make less power? Am I moving closer and closer to detonation? Do I need a new shortblock? longblock?

I know these are pretty newbish questions, but please bear with me :)

Thanks
 

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stanggt00 said:
However, superchargers are easier to install, make power at lower rpms, and are alot cheaper.

yes they are easier to install, but with a properly setup Turbo, you will be at full boost much sooner then a Centrifugal Supercharger and possibly a Roots blowe as well.

If you want to increase boost, just change the pulley.

LOL!, I guess you never heard of the phrase "Turning up the Wick" on Turbo'd cars. No pully change necessary.
 

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Discussion Starter · #9 · (Edited)
no need for laughing at people... he was just trying to help
 

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6 years down the line, your engine's wore out...you'd just need a new short block unless you've done some kinda damage to the heads.

I think that the supercharger would put more stress on the main bearings due to increased tension on the crank snout...other than that I really don't know what other differences there would be in engine wear....w/ a good tune and a reputable engine builder either will last a long time.

SJ
 

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yea you also have to remember how fast that turbo is spinning. more things can go wrong with a turo than a supercharger. some of the fastest cars use superchargers remember that.
 

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Discussion Starter · #12 ·
top fuels are super charged....

w/ a good tune and a reputable engine builder either will last a long time.
that compells me to go super :) Mainly because its so much cheaper. I got a few more newb questions for you guys and then I promise I'll leave you alone for at least....... a day ;) What super charger causes the least amount of engine wear? Should I run an intercooler? I know mainly the intercooler is used to make the charge denser... but doesn't it also bring down engine heat?

Thanks for all the input!
 

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stangfreak said:
yea you also have to remember how fast that turbo is spinning. more things can go wrong with a turo than a supercharger. some of the fastest cars use superchargers remember that.
Your right, some of the fastest cars use a supercharger, but then again, some of the fastest cars are also Turbo Charged, and yet again some of the fastest cars use Nitrous . . . Your point being?

Let's see the record holders right now for Mod Motor with Power adder are???? You guessed it Turboed.

8 second 2V, Turbo Power.
7 second 4V, Turbo Power.

As far as spinning, I guess you have never heard of anyone overspinning their S/C and grenading it.

Look this thread is not which power adder is better, for every S/C you can name, Turbos and Nitrous can be named just as often.

Now let's get back to the subject of this thread.
 

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Discussion Starter · #14 · (Edited)
haha thanks.... I don't think forced induction is for me though. I don't have the budget to upgade my shortblock and tranny.

Thanks for all the info
 

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Bottom line to make life simple...

If you can't pay, don't play!

Performance mods are costly, if you can accept that up front, great, more luck to you. But if you can't afford the catastrophic rebuild, don't mess with it.

Joe
 

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Discussion Starter · #16 ·
LodBot said:
I don't think forced induction is for me though. I don't have the budget to upgade my shortblock and tranny.
I realized that :(
 

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Well, forced induction in any form places additional stress on the engine.

In a belt driven application, you have the additional load placed on the crankshaft (if belt tension is higher, then the belt is trying to snatch the crank in the direction of the load) and the load imposed by the compressor may place an additional load on the crank as well (I sure it does, but to what degree I cannot say, although I think belt tension would create a bigger problem).

As for the compressed intake charge, it tends to be heated beyond typical operating temps which places a higher thermal load on the engine (evidenced by the need for ignition timing changes and better fuels). Which I suppose is one reason the bsfc is higher on S/C'd engines since additional fuel is used to cool the intake charge (this seems to be the simple straight forward answer). Then again (and this is just a complete shot in the dark) bsfc might also be higher because of turbulent air being pushed around the intake tract creating lean or rich condtions which are beyond the intake manifold or port to control.

And you also have higher cylinder pressures to deal with (a result of generating higher horsepower in any application)

All of these things combine to place additional stress on any motor.

Now is the engine in stock form designed to handle these stresses

??

I can say the 4.6 is light years ahead of the 5.0 in terms of durability.

As for forged components, in an apples to apples comparison they tend to be more forgiving than a cast part due to thier ductile nature (eg; a glass window (cast) compared to a plexi-glass window (forged) )

Also forged materials typically possess better material properties owing to the forging process (better grain, less porosity, higher density, ect.) and in automotive aftermarket scenarios the forged parts are often designed to work in higher stressed applications which means they are inherently tougher.

Another thing to consider is engine oil (which is to say the actual bearings in the motor) and the oil's ability to handle higher heat (it also acts as a thermal conductor).


what you need to ask youself is what level of power are you trying to accomplish and with what budget?

If money is more abundant than sense (not being derogatory, and this is a valid approach) you can slap the strongest components on the motor and forget about it.

If you are using in minimalist approach, then you need to examine each aspect of the engine and determine the relative margin of safety designed into the part (probably pretty hard since you have to have engineering data at both ends of the problem or rely on the expertise of somebody)

Or you are approaching it like most people, a mix of the above due to part/financial constraints.
 

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hey calypso, you got a problem chief? why you gotta give an attitude answer. solidsnake is right, this forum isnt that friendly. im from new york i aint tryin to hear no bs like that. :shootbird
:shootbird :shootbird :shootbird :shootbird :shootbird :shootbird :shootbird :shootbird :shootbird :shootbird. for you buddy
 

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Discussion Starter · #20 ·
stangfreak there isn't any need for that. I dont' want to start a big argument here... but personally I found these forums to be very helpful and filled with nice/knowledgable people. calypso was just trying to help, and please don't respond with a big message saying that I dont' know anything and that calypso is a total ass because honestly.... no one wants to hear that and 1/2 of it isn't true (the calypso being an ass part :D)

Thanks
 
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