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Twin Scroll Turbos?? Monster Spool.. FACT or FICTION???

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Old May 4, 2010 | 07:38 AM
  #136  
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why not use a gtx40r, are they out yet?
Old May 4, 2010 | 07:40 AM
  #137  
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Originally Posted by JohnBradley
People that are proponents of twin scroll designs are the ones that actually want to drive the car and feel the rush as much as they can, not just at the end of the line when its time to shift. Drag racers and highway racers just need "top end" and know that power is only a shift away at best. It should be less of a debate and be more a lifestyle choice lol.
This post needs to become a sticky someplace!

How many EVO owners bought an EVO to drag race only with? There isn't even Nopi or import drag racing anymore - haha. I guess forum records are the new fad, no thanks, I like drivng my car and if I can quote TedB, 'moving the gas pedal up-down-up-down and not just holding it down for 8, 9, 10 seconds...'. That line is a freaking classic - right up there with Mike callig Twinscroll 'hype' lmao...

Last edited by Philthy748; May 4, 2010 at 07:42 AM.
Old May 4, 2010 | 07:46 AM
  #138  
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The problem though is there is not a single ounce of DATA to back up the claim of TS providing better response.

It's all opinion.

I can put a smaller SS turbine housing on a turbo and drop peak HP while picking up mid-range, which seem to be what the vast majority of TS setups show.
Old May 4, 2010 | 07:52 AM
  #139  
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Originally Posted by 03whitegsr
The problem though is there is not a single ounce of DATA to back up the claim of TS providing better response.

It's all opinion.

I can put a smaller SS turbine housing on a turbo and drop peak HP while picking up mid-range, which seem to be what the vast majority of TS setups show.
because all the data thats ever been shown are only dyno runs and not showing transient response
the low rpm pulls are not a road "whats faster" scenario in any form be it a street race,drag,circuit
Old May 4, 2010 | 07:57 AM
  #140  
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Originally Posted by JohnBradley
People that are proponents of twin scroll designs are the ones that actually want to drive the car and feel the rush as much as they can, not just at the end of the line when its time to shift. ... It should be less of a debate and be more a lifestyle choice lol.
Amen. My thinking was straightforward and logical:

Pick a realistic power target and build a TS setup to get there. That ensures I get what I want in a package that delivers the best possible transient response, spool characteristics, and broad (read: usable) powerband. Why? Because 99% of my driving time is done on the street, at less than 100% TP, and I want the complete driving experience for my investment.

A car that is more powerful, but with inferior response would be at a disadvantage in a real world situation (e.g. one with corners and curves). And on the highway, 600whp gets to jail-time speeds so quickly that an extra 100whp won't have the time or distance to show it without doing something truly worthy of the Darwin Awards.

If you're a dedicated drag racer, where the difference between 600 and 700whp is measured in the blink of an eye, who cares if it drives like a pig at <100% TP?

I've been through different turbos and various hardware, and I have reached a point whereby I feel like I would change nothing. It's not easy to find that. Anyone with half-a-brain who comes through this area, I'll let you drive my car, and you'll get it before you ever put your foot into it. This is perhaps the only instance where the butt-dyno reveals things a real dyno cannot.

FYI
Old May 4, 2010 | 08:01 AM
  #141  
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Originally Posted by 03whitegsr
The problem though is there is not a single ounce of DATA to back up the claim of TS providing better response.

It's all opinion.
Opinion? There's a TON of published data from real life engneers that explain and provide sceintific proof that TS provides better transient response and improves boost threshold... There are also dozens of people, including myself, that have switched from SS to TS and provided our observations...

Heck, the first forced induction book I ever read, Maxium Boost, goes into detail on the benefits of TS and that book was written a Long tme ago by a Very respected forced induction Guru... If you don't want to see that data, you never will unless you try it for yourself.
Old May 4, 2010 | 08:04 AM
  #142  
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am i barking up the wrong tree? area in red would be hit earlier with TS
boost over time
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Old May 4, 2010 | 08:10 AM
  #143  
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Originally Posted by 03whitegsr
I can put a smaller SS turbine housing on a turbo and drop peak HP while picking up mid-range, which seem to be what the vast majority of TS setups show.
If the two situations were equal as you suggest, than there shouldn't be a world of observable difference between the transient response of a 35R car with .63 A/R T3 and 1.06 A/R TS T4, but there is. The interesting thing is one doesn't even need to get the turbo into boost to know the difference. Looking at housing design, it's easy to explain why it is what it is. Just consider NA collector design while looking at the difference between a primary runner exit and an open T3 housing.

Now, I know the difference from first-hand driving experiences, so I see no mystery, no need for speculation. Take it or leave it.

Last edited by Ted B; May 4, 2010 at 09:17 AM.
Old May 4, 2010 | 09:04 AM
  #144  
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Originally Posted by 03whitegsr
The problem though is there is not a single ounce of DATA to back up the claim of TS providing better response.
Eh? So you think the engineers at BMW are idiots? You drive one (based on your info under your screen name), you know they make some of the most high tech engines with the best HP/L outside of Ferrari. You also know they raced F1. If there's no 'data' to back it up, think they would bother with TS?

Seriously, there are a few hundred, if not thousand guys with PhDs that have worked on vehicles and spec'd out TS systems for them. There's a reason Mitsu uses TS. And Subaru. And GM. And Catapillar if you want to get into industrial stuff. I mean, Catapillar probably only makes a couple billion in revenue a year, what do they know?
Old May 4, 2010 | 09:31 AM
  #145  
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I'm not sure what else there is to discuss here. It's the same old pattern time and time again. Those with the least comparative experience are the most skeptical if not downright critical. Meanwhile, those with the benefit of experience with both configurations would revert back in a heartbeat if TS wasn't what they expected, but that doesn't often happen. I don't think I need to bother explaining what that implies.

Some don't care what the car does so long as the dyno says 700whp somewhere in the chart. Others aren't satisfied with something that drives like on/off switch (mostly off) and want something different. As Aaron put it succinctly, it's a lifestyle choice.

The bottom line is that TS technology continues to show up in OE and respectable racing efforts. That isn't by accident, and is beyond debate.
Old May 4, 2010 | 09:49 AM
  #146  
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This thread should just be a sticky and then when this same old topic comes up again in a few weeks/months, this thread won't be buried in the search option...
Old May 4, 2010 | 09:51 AM
  #147  
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this is a good read as well. http://www.modified.com/tech/modp-09...ign/index.html
the main advantage of a twin is the throttle response which is important for road racing. so i guess it depends on what you want to use the car for and the budget that you have.

it would be nice to have real data to back this up.
Old May 4, 2010 | 10:56 AM
  #148  
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Originally Posted by Ted B
It's the same old pattern time and time again. Those with the least comparative experience are the most skeptical if not downright critical.
This reminds me of another Evo community debate regarding when ECU boost came out. The people with manual boost controllers didn't want to give them up, so they tried to poke holes in the advantages of ECU boost.
Old May 4, 2010 | 11:17 AM
  #149  
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Originally Posted by Ted B
Amen. My thinking was straightforward and logical:

Pick a realistic power target and build a TS setup to get there. That ensures I get what I want in a package that delivers the best possible transient response, spool characteristics, and broad (read: usable) powerband. Why? Because 99% of my driving time is done on the street, at less than 100% TP, and I want the complete driving experience for my investment.

A car that is more powerful, but with inferior response would be at a disadvantage in a real world situation (e.g. one with corners and curves). And on the highway, 600whp gets to jail-time speeds so quickly that an extra 100whp won't have the time or distance to show it without doing something truly worthy of the Darwin Awards.

If you're a dedicated drag racer, where the difference between 600 and 700whp is measured in the blink of an eye, who cares if it drives like a pig at <100% TP?

I've been through different turbos and various hardware, and I have reached a point whereby I feel like I would change nothing. It's not easy to find that. Anyone with half-a-brain who comes through this area, I'll let you drive my car, and you'll get it before you ever put your foot into it. This is perhaps the only instance where the butt-dyno reveals things a real dyno cannot.

FYI
Makes me wish I was a little closer to the east coast, even for just a ride...

Last edited by jasnm21; May 4, 2010 at 11:19 AM.
Old May 4, 2010 | 11:35 AM
  #150  
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I drove ted's car ! I felt that rush your talking about

Originally Posted by JohnBradley
People that are proponents of twin scroll designs are the ones that actually want to drive the car and feel the rush as much as they can, not just at the end of the line when its time to shift. Drag racers and highway racers just need "top end" and know that power is only a shift away at best. It should be less of a debate and be more a lifestyle choice lol.

my 2 cents.

Last edited by mega-z; May 4, 2010 at 11:39 AM.


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