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Discussion Starter #1
Not trying to start a debate, but which theoretically is less stressful on the tranny?
 

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MonStar1120 said:
Not trying to start a debate, but which theoretically is less stressful on the tranny?
The SC would since hte powerband would be more linear instead of a freight train of power.
 

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Discussion Starter #3
Now see that makes me want to go with a S/C with a BOV so I would feel more comfortable pushing the car to its limits. :(
 

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SC would be your best bet..... It all depends on how you drive. But, therotically the automatic is better.


Ryan
 

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Discussion Starter #5
Yeah but the automatic is 100x less fun to drive than the 5-speed. ;)

But anyway, for a daily driver shifting at 3-4K RPM's what is more noticeable the S/C or turbo? Because with turbo it doesn't reach full boost until a little over 4K RPM's, correct?
 

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MonStar1120 said:
Yeah but the automatic is 100x less fun to drive than the 5-speed. ;)

But anyway, for a daily driver shifting at 3-4K RPM's what is more noticeable the S/C or turbo? Because with turbo it doesn't reach full boost until a little over 4K RPM's, correct?
That depends on which turbo setup you have. some setups gain full boost @ 2.5k ie Garrett GT35R bb turbo
 

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MonStar1120 said:
Yeah but the automatic is 100x less fun to drive than the 5-speed. ;)

But anyway, for a daily driver shifting at 3-4K RPM's what is more noticeable the S/C or turbo? Because with turbo it doesn't reach full boost until a little over 4K RPM's, correct?
But for daily driving, you usually aren't slamming down on the gas, and thus you're not building any boost. You will be in vacuum, and so it will be no different than driving with no turbo/supercharger.

Anyways, since the s/c has a linear torque curve, the power increase it provides isn't nearly as noticeable as what the turbo would provide.
 

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Discussion Starter #8
The S/C power increase isn't nearly as noticeable? I'm not sure what you mean, since regardless of the powerband 300 RWHP is 300 RWHP. I really want to drive in both a supercharged and turbo'd IS, I think. Because in daily driving if a turbo'd IS feels no different than a regular IS, I think I would rather go with the smoother S/C.
 

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i am boosted with supercharger.

since the power curve is linear..you dont feel the g-force or the pull of a turbo.


if you want the g-force feeling, go with turbo.
 

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MonStar1120 said:
The S/C power increase isn't nearly as noticeable? I'm not sure what you mean, since regardless of the powerband 300 RWHP is 300 RWHP. I really want to drive in both a supercharged and turbo'd IS, I think. Because in daily driving if a turbo'd IS feels no different than a regular IS, I think I would rather go with the smoother S/C.
Hm, I guess you greatly misunderstood me. If your not accelerating hard, you won't be putting the engine under a significant load, and due to this fact, you won't be making much boost pressure. When driving normally, a turbo, supercharger, and n/a engine would perform and act fairly the same way.

In regards to the powerband, you need to look at dyno graphs of both turbo and supercharged IS's, and observe the differences between the torque curves. If you have any inquires regarding this particular issue, just ask in this thread.
 

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MonStar1120 said:
Yeah but the automatic is 100x less fun to drive than the 5-speed. ;)

But anyway, for a daily driver shifting at 3-4K RPM's what is more noticeable the S/C or turbo? Because with turbo it doesn't reach full boost until a little over 4K RPM's, correct?
mine is setup to reach max boost at 4.5k

driving daily under 4000 feels like driving a regular is300 with bolt-ons. get on it, and the car transforms into something else
 

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MonStar1120 said:
The S/C power increase isn't nearly as noticeable? I'm not sure what you mean, since regardless of the powerband 300 RWHP is 300 RWHP. I really want to drive in both a supercharged and turbo'd IS, I think. Because in daily driving if a turbo'd IS feels no different than a regular IS, I think I would rather go with the smoother S/C.
you are GREATLY mistaken here. 300 RWHP SC is NOT the same as 300 RWHP turbo. Not even close to being the same. THe turbo will have MORE usable power through the power band. The SC will reach 300 RWHP peak, while the turbo will give it to you as soon as you reach max boost all the way to redline.

To simply asnwer your question to put all speculation aside, the turbo will be more strenuous on your transmission. Lets put it this way....
you have a coke can, you slowly try and balance yourself on it, if you be careful enough, you can do it. Now try to do the same thing quickly, you definetely will crush the can. Same thing with turbo and supercharger. The SC is less strenuous.

Which car will be faster?? the Turbo with 300 RWHP will rape the SC with 300 RWHP hands down.

PS... trying to skimp and be scared of something breaking, you should stay away from boost. I tell that to everyone i do a kit for. 90% of them dont listen and they bust something then get discouraged.
 

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Malekreza11 said:
you are GREATLY mistaken here. 300 RWHP SC is NOT the same as 300 RWHP turbo. Not even close to being the same. THe turbo will have MORE usable power through the power band. The SC will reach 300 RWHP peak, while the turbo will give it to you as soon as you reach max boost all the way to redline.

To simply asnwer your question to put all speculation aside, the turbo will be more strenuous on your transmission. Lets put it this way....
you have a coke can, you slowly try and balance yourself on it, if you be careful enough, you can do it. Now try to do the same thing quickly, you definetely will crush the can. Same thing with turbo and supercharger. The SC is less strenuous.

Which car will be faster?? the Turbo with 300 RWHP will rape the SC with 300 RWHP hands down.

PS... trying to skimp and be scared of something breaking, you should stay away from boost. I tell that to everyone i do a kit for. 90% of them dont listen and they bust something then get discouraged.

i give you some +rep+ malek.

the sc is less strenous because of the power curve. you hit the full whp and full wtq at or near redline. Hence the linear curve and the "luxury" feeling. there is no sudden pull or g-force like a turbo would give you.


the turbo on the other hand can hit FULL WHP AND WTQ to whatever you set it to.

example:

kuuligan = 4.5k
 

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Hirun said:
i give you some +rep+ malek.

the sc is less strenous because of the power curve. you hit the full whp and full wtq at or near redline. Hence the linear curve and the "luxury" feeling. there is no sudden pull or g-force like a turbo would give you.


the turbo on the other hand can hit FULL WHP AND WTQ to whatever you set it to.

example:

kuuligan = 4.5k
full power on a turbo is achieved when the turbo reaches its max spool. THis is dependent on the type of turbo.

For example, a PFS 60-1 HIFI turbo will hit max boost around 3900 RPM while a GT35R can hit max boost around 2.5k.
 

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Malekreza11 said:
full power on a turbo is achieved when the turbo reaches its max spool. THis is dependent on the type of turbo.

For example, a PFS 60-1 HIFI turbo will hit max boost around 3900 RPM while a GT35R can hit max boost around 2.5k.
Hm, I was under the impression that the 60-1 HIFI (which PFS no longer uses btw) hit max boost at 2.5-3k (7psi PFS stage 1). I undertand what you're saying though; each individual turbocharger will fit its certain niche in terms of application.
 

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Malekreza11 said:
full power on a turbo is achieved when the turbo reaches its max spool. THis is dependent on the type of turbo.

For example, a PFS 60-1 HIFI turbo will hit max boost around 3900 RPM while a GT35R can hit max boost around 2.5k.
Just because the turbo is @ full boost, doesnt mean your making the most power as soon as full boost is reached.

A lot of other factors come into play. You can have full boost reached by 2-2.5k for example, but still not hit the point on the power band where your making the most power.This point could be @ 3.5k or as late as 5.5k. Only a dyno could tell you these things.
 

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myMUSICveins said:
Just because the turbo is @ full boost, doesnt mean your making the most power as soon as full boost is reached.

A lot of other factors come into play. You can have full boost reached by 2-2.5k for example, but still not hit the point on the power band where your making the most power.This point could be @ 3.5k or as late as 5.5k. Only a dyno could tell you these things.
that is correct. Remember hp = rpm x tq

Correction on my earlier statement. Max boost is achieved at just under 4K, but max hp is achieved slightly over 4.5K

sorry for the misconception
 

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kuuligan said:
that is correct. Remember hp = rpm x tq

Correction on my earlier statement. Max boost is achieved at just under 4K, but max hp is achieved slightly over 4.5K

sorry for the misconception

really?

hmm..

so the only reason why the supercharger is slower than a turbo is because it hits max hp at redline or really close to it while turbo has about 1k-2k of max hp?

scenario: 300whp turbo and s\c.

or is it because the supercharger is slower than a turbo because it produces a lot less WTQ than a turbo kit?


help this confused Hirun out. =]
+rep+ for anyone that helps me out.

i have been misinformed so now i need to get my facts straight.
 

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Hirun said:
really?

hmm..

so the only reason why the supercharger is slower than a turbo is because it hits max hp at redline or really close to it while turbo has about 1k-2k of max hp?

scenario: 300whp turbo and s\c.

or is it because the supercharger is slower than a turbo because it produces a lot less WTQ than a turbo kit?


help this confused Hirun out. =]
+rep+ for anyone that helps me out.

i have been misinformed so now i need to get my facts straight.
I don't care about the rep, but I'll do my best to answer the question.

First of all, I wouldn’t simply assume every 300whp turbo setup will dominate every 300whp S/C setup. You really need to take a look @ a dyno graph to understand how power is put to the ground.

Secondly, just because a car is making more power than another, doesn’t always mean it can effectively put it to the ground to make for a faster time. (1/4)

Take a look @ this dyno:
http://7mpower.com/raymond_khublal/raymond_khublal_dyno.jpg

You can see that @ ~ 2.5k he’s making ~100rwhp, and @ ~ 3k he’s making ~200whp. @ ~ 3.2k he’s making ~ 290whp, and peaks @ ~ 5.8k making ~ 400-418 RWHP.

You can see he makes close to peak TQ @ ~3.2k @ ~ 450rwtq. His TQ stays pretty solid until ~ 5.2k.

Now, if I were him I would be shifting around 5.5k as long as my next gear placed me after 3.2k.

That dyno is what they call a VERY useable power band. His length of time in useable power is very nice, with minimal lag. He’s getting into some real power @ early as 3k.

-----------

This next dyno looks very different:
http://7mpower.com/alan_jordan/alan_jordan_dyno.jpg

This guy is making very little power all the way to about 3.7k, so obviously quite a bit more lag. He’s really not making any real power until around 4k, but @ ~ 4.3k, hold on tight, because from here until 6.2k and probably higher your making gobs of HP and TQ.

I didn’t type it all out, what his HP was @ what RPM, as I figured you can probably by now read it yourself and see.

---
So, what does this mean? The first car makes decent power much earlier, but less power @ the top of the power band. It probably means the first car will have the jump on the second, assuming he can keep traction. Once the second car gets into his power band however, he’s going to start reeling in the first car. Remember you really only notice lag in first gear. After first, when you go into the next gear, your RPMs are high enough to make power almost instantly.

On the street, the second car would probably win, as its harder to keep traction on the street. Also this is assuming nobody has any slicks on. It is hard to keep traction with lots of TQ in the lower RPM's as the tire isn’t rolling very fast yet.

So unless the first car knows how to launch correctly, and avoid massive wheel spin, the second car gets a good launch, looses little traction, and gets into his power band, and uses his superior power to blow past the first car.

Who would really be faster? I don't know, lots of factors, time for a track :)
 
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myMUSICveins said:
I don't care about the rep, but I'll do my best to answer the question.

First of all, I wouldn’t simply assume every 300whp turbo setup will dominate every 300whp S/C setup. You really need to take a look @ a dyno graph to understand how power is put to the ground.

Secondly, just because a car is making more power than another, doesn’t always mean it can effectively put it to the ground to make for a faster time. (1/4)

Take a look @ this dyno:
http://7mpower.com/raymond_khublal/raymond_khublal_dyno.jpg

You can see that @ ~ 2.5k he’s making ~100rwhp, and @ ~ 3k he’s making ~200whp. @ ~ 3.2k he’s making ~ 290whp, and peaks @ ~ 5.8k making ~ 400-418 RWHP.

You can see he makes close to peak TQ @ ~3.2k @ ~ 450rwtq. His TQ stays pretty solid until ~ 5.2k.

Now, if I were him I would be shifting around 5.5k as long as my next gear placed me after 3.2k.

That dyno is what they call a VERY useable power band. His length of time in useable power is very nice, with minimal lag. He’s getting into some real power @ early as 3k.

-----------

This next dyno looks very different:
http://7mpower.com/alan_jordan/alan_jordan_dyno.jpg

This guy is making very little power all the way to about 3.7k, so obviously quite a bit more lag. He’s really not making any real power until around 4k, but @ ~ 4.3k, hold on tight, because from here until 6.2k and probably higher your making gobs of HP and TQ.

I didn’t type it all out, what his HP was @ what RPM, as I figured you can probably by now read it yourself and see.

---
So, what does this mean? The first car makes decent power much earlier, but less power @ the top of the power band. It probably means the first car will have the jump on the second, assuming he can keep traction. Once the second car gets into his power band however, he’s going to start reeling in the first car. Remember you really only notice lag in first gear. After first, when you go into the next gear, your RPMs are high enough to make power almost instantly.

On the street, the second car would probably win, as its harder to keep traction on the street. Also this is assuming nobody has any slicks on. It is hard to keep traction with lots of TQ in the lower RPM's as the tire isn’t rolling very fast yet.

So unless the first car knows how to launch correctly, and avoid massive wheel spin, the second car gets a good launch, looses little traction, and gets into his power band, and uses his superior power to blow past the first car.

Who would really be faster? I don't know, lots of factors, time for a track :)

thanks a lot for the help +rep+

on my supercharger..my curve keeps rising til it is near redline to redline where it hits its max hp.

i dont know where my dynosheet is right now.. :*(

i want to post it up and also check my torque curve..
 
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