SPEC Clutch Proprietary Clutch + Single Mass Flywheel Combos are now available to order!

Ruskee

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Lighter flywheel does put more stress on transmission, no? At least in aggressive driving situations. Because there's less dampening in between, doesn't that mean it transfers the power more abruptly?



 

BoostedDreams

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Lighter flywheel does put more stress on transmission, no? At least in aggressive driving situations. Because there's less dampening in between, doesn't that mean it transfers the power more abruptly?
I would like to know this as well before making final decision. I would think a lightened flywheel would extend the engine life as there is less stress on the parts and bearings, however, a drag car will probably not benefit from it as a heavier flywheel will hold it's kinetic energy better than a lightweight flywheel.
Any concern with dropping too many rpm's during boost between shifts? @Two Step Performance
 
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Two Step Performance

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That’s not bad at all really. I might just pull the trigger on the lightweight one.

Someone mentioned that there is a bit of a power loss at higher speeds with a light flywheel? Is there any truth to this ? @Two Step Performance
That is new to me. With a lightweight flywheel, you reduce rotating mass, decreasing drivetrain power loss, and increase power to the wheels. It has not been tested in this vehicle, but I do not think it is unreasonable to think one may could pick up to 10 hp on a chassis dyno.
 
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Lighter flywheel does put more stress on transmission, no? At least in aggressive driving situations. Because there's less dampening in between, doesn't that mean it transfers the power more abruptly?
I would like to know this as well before making final decision. I would think a lightened flywheel would extend the engine life as there is less stress on the parts and bearings, however, a drag car will probably not benefit from it as a heavier flywheel will hold it's kinetic energy better than a lightweight flywheel.
Any concern with dropping too many rpm's during boost between shifts? @Two Step Performance
No issues with the RPMs dropping faster than one can shift. It is typically accepted that the lighter rotating mass is less stressful on both the engine and transmission.
 
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MavicTB

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That is new to me. With a lightweight flywheel, you reduce rotating mass, decreasing drivetrain power loss, and increase power to the wheels. It has not been tested in this vehicle, but I do not think it is unreasonable to think one may could pick up to 10 hp on a chassis dyno.
Its not a power loss but a momentum loss, you don't lose power you make more as you said, but going up hills and such you have less momentum and need to use more throttle to maintain speed. Its minimal in my experience though. The biggest drawback of a LW flywheel IMO is accelerating from a stop in normal driving conditions ie. stop and go traffic. Again this is minimal in my experience on low displacement cars fitted with a LW flywheel.

All that said, I am waiting to change my clutch/flywheel out until it is needed, but when that time comes this seems to be a great option.
 

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joshhjackson2112

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d1zguy

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I was thinking about the 3+ but not sure what the difference between 3 and 3+ are. I am a super noob but learning.
only more ft lbs and less money in your bank. I don't plan on ever running more than 447 ft lbs at the flywheel
 

d1zguy

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Yes, stage 1-2+ offer a more streetable and stock like engagement stage 3 on up engage more aggressively the higher you go up. Meaning on stage 5 to get the car to move you will need high revs and or sporadic application of the clutch pedal.

Ever hear an old d16y7 manual civic go through the gear and that lame exhaust note as the clutch is released on the upshift. That's because the clutch material slips to slow down the engine coupled with a heavy stock flywheel it extends the exhaust farts. Vs a stage 5 clutch that will get rid of the extended clutch farts and eliminate the slip and more heat resistant at the expense of city drivability.

This is why DCT cars like the Golf GTI or BMW M5 sound like shotguns going off when upshifting DCT's are essentially stage 5+ clutches between shifts.

I have driven and installed 3 lightwieght flywheels
a 13 lbs flywheel on a 2000 gti GLX VR6. stage 2 massive noise from trans, but good drivability no snap shifts required, faster rev up and easy to rev match downshift.
a stage 3 on a 2005 audi S4 . no trans noise but the rotational momentum lost in such a lightweight flywheel on that engine (short stroke) required really fast downshifts or upshifts to get it just right. Good drivability but no lazy shifting or rev matching allowed.
1987 bmw 325e with dual mass, swapped in early model single mass about ~8 lbs lost. Faster rev up and no snap shifts needed

The L15 drives like a truck diesel engine so I expect it to be more managable like the VW GTI and not the S4 that required snap shifts at all times. But I'd rather not chance it and wait for a more sensible drop in weight ~10lbs and get a more similar experience to the BMW 325e's with more torque on tap. Mind you none of these cars had an inadequate clutch or flywheel from factory to begin with. tnx honda

Come to think of it all of the Honda cars I've owned have been fitted with inadequate clutch and pressure plate combos from factory. My SI and my AP2 S2000. They went from single mass in AP1 (much lighter) to Dual mass in AP2 BUT kept the same pressure plate and clutch from the AP1. Causing 1. massive amounts of rev hang, 2. on quick shifts slipping the clutch aiding to that extended fart sounds d16y7's have. I took it to a track session and had to slow down my shifts about 1 sec just enough for the engine to start reving down on it's own before engaging the clutch. Screw you Honda
 
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BoostedDreams

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After some self debate, I’m going to wait for the steel option. I need the car as driver friendly as possible since I do real estate and often will have clients in the vehicle with me.
The stage 2+ seems like the best option for my needs with flex fuel and TSP stage 2. I don’t plan on adding more power, I just want to use the power that i currently have without the stupid clutch slipping!
Also, a spec rep told me that the steel flywheels should be up for sale thru @Two Step Performance by end of next week
 
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davemarco

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Looking forward to member reviews!
 

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