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For some reason I could not type in my OP without losing the pop up keyboard on iPhone 5 ... Mods should look into this.

Anyways, i was thinkig about how the FiST sounds when revving the engine. I suspect that either the ST has a heavy crank and/or flywheel, or the boost blows by in the cylinders through the valve overlap. I'm not sure if anyone follows me, but have't anyone noticed how "uneagerly" the revs drop off while revving the engine at idle? Its almost like it resembles the R32 sound (VW R32 with 3.2L V6). The revs jump up fast, yet stay up and don't fall off as quickly.

Have any of the tuning companies looked into this?
By lightning the crank and/or flywheel, I suspect more throttle response and minimal hp can be gained.

The downside would be unless you shift very quickly, you would drop out of boost.

Let me know what you guys think.
 

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You lighten the flywheel and its going to take more throttle input/inertia to get it off the line, but yes it'll rev a bit more freely. Not sure about you, but I don't wanna dig into a brand new motor and spend a few thousand to lighten a crankshaft to gain a few more hp and have it decelerate quicker, but that's just me lol. I feel that there are much better area's to spend time/money on that'll "pay out" more performance-wise.
 

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It'll probably happen sooner or later but probably not many people in the market until the clutches start nearing the end of life.

And, OP, we don't even have track brake pads to pick from yet. So one thing at a time :)
 

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It will never happen. A lighter crank will cost a large amount of money and in this segment, people want best bang for their buck.

I am not sure if this car uses one, but most new cars do, but the Dual Mass Flywheel is a large damper that allows the car to run smoother and dampen vibrations but at the cost of slower revving and the revs do not fall as quickly as they should.

A tune sometimes can help with the rev hang. If you change a car from a dual mass flywheel to a single mass you will get a lot more vibration through the drivetrain as well as a chattering noise. However the car will get up and sprint much more willingly and your revs will drop MUCH faster.

It is somewhat of a give and take.
 

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I had a turbo Subaru with a lot of mods, one of them was a billet flywheel that was about half the weight of the stock flywheel . It made a noticeable difference to the way the vehicle accelerated and responded to throttle inputs and increased horse power. The negative aspects were it would stall easier and was harder to get off the mark on a hill or with a car load of people, especially both and care had to be taken not to smoke up the clutch in those situations.
 

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For some reason I could not type in my OP without losing the pop up keyboard on iPhone 5 ... Mods should look into this.

Anyways, i was thinkig about how the FiST sounds when revving the engine. I suspect that either the ST has a heavy crank and/or flywheel, or the boost blows by in the cylinders through the valve overlap. I'm not sure if anyone follows me, but have't anyone noticed how "uneagerly" the revs drop off while revving the engine at idle? Its almost like it resembles the R32 sound (VW R32 with 3.2L V6). The revs jump up fast, yet stay up and don't fall off as quickly.

Have any of the tuning companies looked into this?
By lightning the crank and/or flywheel, I suspect more throttle response and minimal hp can be gained.

The downside would be unless you shift very quickly, you would drop out of boost.

Let me know what you guys think.
The rev hang is on purpose for emissions reasons. They have been doing this to cars since the 1970's. A tuner can program that out of the mix.
 

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I had a turbo Subaru with a lot of mods, one of them was a billet flywheel that was about half the weight of the stock flywheel . It made a noticeable difference to the way the vehicle accelerated and responded to throttle inputs and increased horse power. The negative aspects were it would stall easier and was harder to get off the mark on a hill or with a car load of people, especially both and care had to be taken not to smoke up the clutch in those situations.
With Hill Assist, that last part is much less a concern.
 

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The rev hang is on purpose for emissions reasons. They have been doing this to cars since the 1970's. A tuner can program that out of the mix.

This. Slamming the throttle body closed introduces a momentary very rich condition and lets all sorts of unburned hydrocarbons through.

Has anybody had any luck with a tuner fixing the rev hang?
 
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