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Sorry man you lost me....i said they are more NEEDY . I.E...steady flow of oil, cool down time/turbo timer, oil changed frequently, intercooler, btm, boost control, guages and all that kind of stuff if you want to run at a high boost. Superchargers you don't have to worry about all that or buy most that equipment.

For just all out power you can boost more on a turbo basically cause you can control it using the boost control. the only way to increase the boost on a super is to buy a bigger pulley so obviously the turbo can over power the supercharger .

Originally posted by IS300GTE:

that first line is not true. you can make the same amount of hp from a turbo, maybe more actually, as you can with a supercharger. the turbo can push the same amount of CFM into the motor, add that with spark fuel and timing, and the motor can potentially make the same power with either add-on. the turbo might even make more power at the wheels, because it doesn't have parasitic drag like a supercharger does.
 

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both are very great ways to gain hp. with my opinion. i would chose a turbo over a supercharger anyday. a turbo is free power given by the exhaust pressure. basically it is just recycling the air. less stress on the motor. but, with a supercharger. it is belt driven. so it takes power to make power. just like how the a/c works, or power steering. the great thing about the super charger is that it is on all the time. great for road racing. very wide power band. but is limited by a pulley. a turbo can run as much boost as desired. just make sure you dont run too much. lolz. sorry, if that sounds all broken up. just very long night. hopefully, the point did get across though. also, a turbo car is much more fun to drive in the higher powerband range. since it just keeps climbing. with a supercharger, the power curve is more flat. with a turbo though. you can also have a very smooth power curve, if the turbo is set up correctly, such as a smaller a/r for less lag. but, with a smaller a/r. your top end will not be as strong. give and take.

[From TEG: It isn't exactly "free". You extract a penalty on the engine with the backpressure you put on the exhaust. You have to make it up by using _more_ boost to get back the lost power. It may not be a mechanical load on the engine, but you put a huge "thermal load" on the engine. Some engines are not suited to turbocharging because of intake/exhaust "overlap". ]

[This message has been edited by TEG (edited November 14, 2000).]
 

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Originally posted by GPR:
Sorry man you lost me....i said they are more NEEDY . I.E...steady flow of oil, cool down time/turbo timer, oil changed frequently, intercooler, btm, boost control, guages and all that kind of stuff if you want to run at a high boost. Superchargers you don't have to worry about all that or buy most that equipment.

For just all out power you can boost more on a turbo basically cause you can control it using the boost control. the only way to increase the boost on a super is to buy a bigger pulley so obviously the turbo can over power the supercharger .
Most of the stuff you listed does come into play with superchargers also. Some superchargers do come with intercoolers or sometype of air cooler. Dont get the idea of "just turning up the boost" always works. That spell disaster if your fuel system cant compensate for all the air your forcing into the engine.
 

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Originally posted by Keith Ta:
both are very great ways to gain hp. with my opinion. i would chose a turbo over a supercharger anyday. a turbo is free power given by the exhaust pressure. basically it is just recycling the air. less stress on the motor. but, with a supercharger. it is belt driven. so it takes power to make power. just like how the a/c works, or power steering. the great thing about the super charger is that it is on all the time. great for road racing. very wide power band. but is limited by a pulley. a turbo can run as much boost as desired. just make sure you dont run too much. lolz. sorry, if that sounds all broken up. just very long night. hopefully, the point did get across though. also, a turbo car is much more fun to drive in the higher powerband range. since it just keeps climbing. with a supercharger, the power curve is more flat. with a turbo though. you can also have a very smooth power curve, if the turbo is set up correctly, such as a smaller a/r for less lag. but, with a smaller a/r. your top end will not be as strong. give and take.
Oh yeah and dont listen to this guy! He knows nothing!

Kev =Þ



[This message has been edited by SupraSport (edited November 14, 2000).]
 

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Originally posted by Keith Ta:
lolz. very funny. do i know you? =P
NO you dont know me. Now get back to putting your engine in your car. One more thing, wheres my drill? Oh yea and those Option videos, id like them back now. That is all.

Kev
 

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lolz. well hey u have to come by. hey come over now, if you want to chill. sorrie i just been working on my car.

Originally posted by SupraSport:
NO you dont know me. Now get back to putting your engine in your car. One more thing, wheres my drill? Oh yea and those Option videos, id like them back now. That is all.

Kev
 

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dang supra guys...you guys taking over the IS300 board too??? especially that keith guy...
jk...

yeah, the turbo car is a bit harder to handle racing around curves. especially in the rain
amhik


the supercharged cars are always a bit more predictable. i'm still not that used to the turbos kicking in while i'm making a turn. keeps you on your toes tho...

as for all the arguments on here, i think they are all valid...but i think it's still a personal preference. someone posted that it depends on what you want it for. if it's for daily driving and not much racing around, i think i'd go with the supercharger. but if you want to do some occasional dicing around with some friends...i'd go with the turbo. nothing feels quite as good as a turbo spoolin and putting you in your seat. and the top end is quite exhilirating...especially going down the freeway at over 150mph...not like i did before or anything...


do your research before choosing one over the other...

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2001 IS300 Graphite Grey
94 Supra TT/6-speed/HardTop
90 Integra
86 Corolla GTS (AE86)
 

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very well put my friend! lolz. as for supra guys taking over.... i doubt that. but, hey they do have supra motors.


Originally posted by HyperMKIV:
dang supra guys...you guys taking over the IS300 board too??? especially that keith guy...
jk...

yeah, the turbo car is a bit harder to handle racing around curves. especially in the rain
amhik


the supercharged cars are always a bit more predictable. i'm still not that used to the turbos kicking in while i'm making a turn. keeps you on your toes tho...

as for all the arguments on here, i think they are all valid...but i think it's still a personal preference. someone posted that it depends on what you want it for. if it's for daily driving and not much racing around, i think i'd go with the supercharger. but if you want to do some occasional dicing around with some friends...i'd go with the turbo. nothing feels quite as good as a turbo spoolin and putting you in your seat. and the top end is quite exhilirating...especially going down the freeway at over 150mph...not like i did before or anything...


do your research before choosing one over the other...

 

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Originally posted by SupraSport:
Most of the stuff you listed does come into play with superchargers also. Some superchargers do come with intercoolers or sometype of air cooler. Dont get the idea of "just turning up the boost" always works. That spell disaster if your fuel system cant compensate for all the air your forcing into the engine.
ok, i said oil/fuel system on an earlier post, if you read it. You can put on an intercooler or a water spray thing but it's not really nessesary compared to a turbo. You can run a supercharger without it and your fine, but all turbo's come with some sort of intercooling system whether it's an FMIC or one of them side ones. Personally i think a reinforced block would help prevent detonation over the fuel system upgrade.

[From TEG: Not all turbos come with intercoolers. Most do these days, but in years past there were plenty of turbos sans intercooler. Yes, it is more common to find a supercharger _without_ an intercooler, but that is often because they are producing less boost, and/or they are mounted on the engine in such a way that it is hard to plumb an intercooler.
A proper A/F ratio is absolutely necessary particularly when running boost. Go ahead - get a reinforced block - but with an overly lean A/F ratio you can damage your valves and pistons over time.]

[This message has been edited by TEG (edited November 15, 2000).]
 

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just a fuel system alone won't do it if you're running excesive boost levels. you really should do everything together. do it right the first time...

my opinion, get the lowest air temp you can. first start with an effecient forced induction product. some superchargers on the market will heat up air tremendously if you spin them too fast. ppl think that more boost is better...not true, remember that boost is relative to temperature. boost is measured by pressure right??? what happens to a ballon (with air in it) when you leave it in the sun??? it expands right??? so...more pressure. so the same thing happens in your car. just because your boost gauge reads higher boost levels, it doesn't mean you get more air...it may actually mean that the air going in is hotter than before. so, my point is, cool air will help. your point about the block is valid, but i think you should think about every small little detail when it comes to making power. why skimp when it comes down to it??? do it right...fuel, air, block...everything...that way, you won't have to worry so much about blowing anything up...

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90 Integra
86 Corolla GTS (AE86)
 

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Originally posted by GPR:
ok, i said oil/fuel system on an earlier post, if you read it. You can put on an intercooler or a water spray thing but it's not really nessesary compared to a turbo. You can run a supercharger without it and your fine, but all turbo's come with some sort of intercooling system whether it's an FMIC or one of them side ones. Personally i think a reinforced block would help prevent detonation over the fuel system upgrade.
True. You can run a Supercharger without a intercooler, you can also run a turbo without a intercooler. You also wont get the same consistant power output due to heated air. Detonation is what it is, detonation...a reinforced block isnt going to stop that. Once you run too lean, no matter how reinforced internals are, that adds up to one thing, thermal melt down. Check the prices on internal upgrades, im sure you would want togo the fuel system route after one glance.


[This message has been edited by SupraSport (edited November 14, 2000).]
 

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true dat one...seems like supra guys really know their forced induction basics huh???


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90 Integra
86 Corolla GTS (AE86)
 

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Wow, there is so much that have been said here. Some of you are knowledgeable and some of you are just ...um lets just say misinformed.

Well here is the scoop, we will compare a turbo to a centrifugal supercharger.

The efficiencies of either of these products completely depend on one major design alone, it depends on the compressor housing, and impeller wheel design. This efficiency is called the adiabatic efficiency of the unit wether a turbo or supercharger.

Well now you are going to ask what is adiabatic efficiency, in laymans terms it is the rate of flow of air vs. heat generated vs. impeller RPMs. Typically good chargers will operate at or about 65-70% efficeincy in the normal operating range. Chargers that are better will operate in a higher efficiency range.

With this said and done what it boils down to is how you spin the impeller wheel. a turbo uses exhaust gases whereas a supercharger uses a belt/pulley system.

There is no such thing as spent/wasted exhaust gas recirculation. Bottom line is it takes power to make power, a turbo creates some form of restriction to the exhaust system so the exhaust gases and the engine has to work harder to push the turbo and exhaust gases out to create the power, don't belive me well then explain why a good free flow exhaust makes more power. So we have established that a turbo does consume HP to spin the turbo.
On the flip side yes it is true that superchargers have a drag effect on the engine, because it uses HP to spin the impeller via the belt. However look at this example: a good designed supercharger will typically consume about 25-30HP to generate 1000HP and gain it back from a well designed free flow exhaust.

So both the turbo and supercharger will consume HP, well then what the heck are the differences.

Well here are the major differences:
1) High HP (>400HP) turbo systems have lag, whereas superchargers have absolutely no lag.
2) Turbo systems are generally expensive, because more parts are required.
3) Superchargers are usually loud with a characteristic whine (not all superchargers are loud, wait for the SRT line of super quiet superchargers).
4) Superchargers have a very linear more manageable power band, vs. peaky power bands for turbos.
5) Both superchargers and turbos can make tremendous HP, not one has an advantage more that the other.
6) You need to run the engine at idle to cool down in a turbo car after some hard driving, no need for this in an S/C car.

Here are some myths clarified:
1) I can make as much boost as I want in a turbo all I have to do is turn a knob: FALSE you will have to get a bigger turbo to make more HP period, yes your boost can go up however you are getting that from heat being generated and the overall adiabatic efficiency of your system is going down. So you CAN't get as much USABLE boost as you want just by turning up the knob. However yes you can adjust the boost in the usable range.
2) Superchargers are parasitic drags on engines: True superchargers do require HP to operate, BUT so does Turbos, from a different source.
3) You can't run more than 10PSI of boost with a supercharger: FALSE, you can run as much boost as your system is designed for, we ran upto 20 PSI of boost in our GS400 from a supercharger before the Head Gasket called it quits (It made 630RWHP)
4) A supercharger creates more strain in your engine because you are always in boost: FALSE, S/C kits that use a blow-off valve are Vacuum 95% of the time and under boost only when you need it, further refining the power curve. And since the power is more linear than abrupt it is actually easier on parts.
5) Rumors say that superchargers are the major power adders of the future: TRUE, due to stricter emmissions laws turbo systems cannot pass cold start emissions laws of 2005, because the CATs in a turbo car require a long time to heat up, thus being ineffective, but S/C systems actually lower the cold start emissions.
6)
 

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Let me just address the "peaky" power delivery of the turbo:



This is the before and after dyno graphs of my Miata at 6psi, untuned. This was pretty much plug it all and see what happened. Since that dyno, I had reworked the fuel pressure and some other things, but still, power delivery is virtually identical to the stock all-motor graph... This is a small BB turbo and gets into boost fast. Anyway, I'm in the middle of rebuilding the system and will be going to 12 psi. Should be fun.


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Tony
'01 Spectra Blue
'94 Turbo Miata

[This message has been edited by webmaster (edited November 14, 2000).]
 

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that guy must be a supra guy too huh??? heh...just kidding...



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90 Integra
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Originally posted by GPR:
Sorry man you lost me....i said they are more NEEDY . I.E...steady flow of oil, cool down time/turbo timer, oil changed frequently, intercooler, btm, boost control, guages and all that kind of stuff if you want to run at a high boost. Superchargers you don't have to worry about all that or buy most that equipment.

For just all out power you can boost more on a turbo basically cause you can control it using the boost control. the only way to increase the boost on a super is to buy a bigger pulley so obviously the turbo can over power the supercharger .

most of that is also necessary for a supercharger install also. also, you can turn the boost up on a turbo only so much, before it becomes totally inefficient and won't make any more power, same with a supercharger, you can only make the drive pulley so small. with either, you just have upgrade to something larger at a certain point.

the reason you can make more power with a turbo, all other things being equal, is because the turbo works off of waste (exhaust gases) while supercharger itself wastes to make power because the motor has to spin it just like a p/s or a/c pump to push air into the motor.
what it boils down to is that both increase the efficiency of the motor, but a turbocharger will increase the efficiency more.
 
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