Bullet Proof Transmission
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From: Miami, FL
Originally Posted by slipstream444,Apr 8 2007, 08:15 AM
You don't loose torque per se; torque is 'stored' in the rotational mass of the flywheel - ultimately to assist the driver during initial takeoff. Heavier flywheels are great for unskilled manual drivers; play better to the least common denominator when mass-producing cars.
The more rotational mass that's in motion, the easier it is at takeoff. The stored energy acts to dampen the initial torque requirements on the engine.
Tradeoffs:
Greater rotational inertia (mass) makes the engine response slower because the engine has to expend more energy to accelerate the greater rotational mass (store energy in the rotational mass). As Newton described: a body in motion will tend to stay in motion until acted on by an external force. This goes both ways, and therefore greater force is also required to slow the heavier rotational mass, and subesquently (unless you increase the internal friction in your engine) your engine will rev-down more slowly. Heavier FW = slower engine response, but easier to drive.
Lower rotational mass requires greater clutch skills at takeoff, and extremely light flywheels require the driver to work harder to rev-match even during casual up-shifting. Otherwise, the engine RPMs drop below optimal shift RPM for the next higher gear, making shifts 'jerky' and increasing the stresses on the next synchro in sequence on the up-shift. Lighter FW = faster engine response, but requires increased level of skill and concentration.
For everyday use - I found the Comptech to be the best compromise.
Additionally, I didn't really notice a difference in performance between the Comptech and the Toda (except the Toda setup slipped under hard acceleration). This leads me to believe the rotational inertia of the two flywheels is close, even though the Comptech's static mass is about 1.7lbs more than the Toda. This leads me to believe the Toda cut too much of its weight from the center (and friction surface) and not enough from the outside radius.
The ACT has a lot of mass removed from the outside radius, which tells me it will have the lowest rotational inertia of the three flywheels (even though its static mass is about the same as the Toda).
I believe the Comptech FW is the perfect FW for daily use, street and occasional track use. The ACT is probably best used by skilled, frequent, competetive autocrossers that need that ever-so-slight edge over the competition (at the cost of daily driveability). I have no information or experience related to the Competition Clutch FW.
The more rotational mass that's in motion, the easier it is at takeoff. The stored energy acts to dampen the initial torque requirements on the engine.
Tradeoffs:
Greater rotational inertia (mass) makes the engine response slower because the engine has to expend more energy to accelerate the greater rotational mass (store energy in the rotational mass). As Newton described: a body in motion will tend to stay in motion until acted on by an external force. This goes both ways, and therefore greater force is also required to slow the heavier rotational mass, and subesquently (unless you increase the internal friction in your engine) your engine will rev-down more slowly. Heavier FW = slower engine response, but easier to drive.
Lower rotational mass requires greater clutch skills at takeoff, and extremely light flywheels require the driver to work harder to rev-match even during casual up-shifting. Otherwise, the engine RPMs drop below optimal shift RPM for the next higher gear, making shifts 'jerky' and increasing the stresses on the next synchro in sequence on the up-shift. Lighter FW = faster engine response, but requires increased level of skill and concentration.
For everyday use - I found the Comptech to be the best compromise.
Additionally, I didn't really notice a difference in performance between the Comptech and the Toda (except the Toda setup slipped under hard acceleration). This leads me to believe the rotational inertia of the two flywheels is close, even though the Comptech's static mass is about 1.7lbs more than the Toda. This leads me to believe the Toda cut too much of its weight from the center (and friction surface) and not enough from the outside radius.
The ACT has a lot of mass removed from the outside radius, which tells me it will have the lowest rotational inertia of the three flywheels (even though its static mass is about the same as the Toda).
I believe the Comptech FW is the perfect FW for daily use, street and occasional track use. The ACT is probably best used by skilled, frequent, competetive autocrossers that need that ever-so-slight edge over the competition (at the cost of daily driveability). I have no information or experience related to the Competition Clutch FW.
I've seen this combo run several other ways with good results asl well.
Just curious. I would have gone with Comptech if it was available, but they were backordered when I did mine.
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Joined: Apr 2003
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From: Temple City
well, comptech is out of business, and i notice hardtopguy replaced teh comptech flywheel with the ACT flywheel, so my options right now for a STOCK car with OEM disc and ACT pp are:
ACT flywheel
Toda flywheel
or the competition clutch flywheel, disc, pp package?
which one's best? kane.s2k any thoughts?
ACT flywheel
Toda flywheel
or the competition clutch flywheel, disc, pp package?
which one's best? kane.s2k any thoughts?
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Joined: Jun 2004
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From: Miami, FL
If you are mostly stock, you can't beat hardtopguy's kit. I believe he says its good for over 400 horsepower. Needless to say any N/A car and probably mildly boosted car is fine with it.
If you are N/A, buying a super high stage clutch disc is just adding needless stress on your drivetrain. Keeping the OEM disc with the ACT pressure plate keeps it very streetable, but gives it a noticecable stiffer and better engagement. The good thing about that is that it won't be shocking the diff as much, an ironman clutch or high stage clutch on an N/A car is overkill.
That being said, if you need a high powered clutch kit, I've heard good things about kane.s2k's kits from local members here. Both are great with customer service.
If you are N/A, buying a super high stage clutch disc is just adding needless stress on your drivetrain. Keeping the OEM disc with the ACT pressure plate keeps it very streetable, but gives it a noticecable stiffer and better engagement. The good thing about that is that it won't be shocking the diff as much, an ironman clutch or high stage clutch on an N/A car is overkill.
That being said, if you need a high powered clutch kit, I've heard good things about kane.s2k's kits from local members here. Both are great with customer service.
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Joined: Apr 2003
Posts: 8,595
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From: Temple City
Originally Posted by Jsmply,Apr 8 2007, 01:11 PM
If you are mostly stock, you can't beat hardtopguy's kit. I believe he says its good for over 400 horsepower. Needless to say any N/A car and probably mildly boosted car is fine with it.
If you are N/A, buying a super high stage clutch disc is just adding needless stress on your drivetrain. Keeping the OEM disc with the ACT pressure plate keeps it very streetable, but gives it a noticecable stiffer and better engagement. The good thing about that is that it won't be shocking the diff as much, an ironman clutch or high stage clutch on an N/A car is overkill.
That being said, if you need a high powered clutch kit, I've heard good things about kane.s2k's kits from local members here. Both are great with customer service.
If you are N/A, buying a super high stage clutch disc is just adding needless stress on your drivetrain. Keeping the OEM disc with the ACT pressure plate keeps it very streetable, but gives it a noticecable stiffer and better engagement. The good thing about that is that it won't be shocking the diff as much, an ironman clutch or high stage clutch on an N/A car is overkill.
That being said, if you need a high powered clutch kit, I've heard good things about kane.s2k's kits from local members here. Both are great with customer service.
Joined: Feb 2004
Posts: 1,491
Likes: 11
From: Pensacola
Originally Posted by Jsmply,Apr 8 2007, 10:16 AM
Could it possible that you would have experianced different results if you had used the same pressure plate (mugen vs. act) on both setups? I only ask because I use the toda flywheel with the ACT pressure plate and stock disc and there is no slip, just grip.
I've seen this combo run several other ways with good results asl well.
Just curious. I would have gone with Comptech if it was available, but they were backordered when I did mine.
I've seen this combo run several other ways with good results asl well.
Just curious. I would have gone with Comptech if it was available, but they were backordered when I did mine.
Joined: Jan 2002
Posts: 1,065
Likes: 10
From: Skopje
Hi Guys..
I had my car NA for 40000km and had super fast Shifting On my S2000 And i shifted super fast 1-2-3-4. Maybe have Grinded the tranny 5-10 times by a small stupid mistakes...in that 40000km
Than i supercharged my S and after that i noticed that I couldn't do that fast shifting at all and i had to wait.....
I was a Moron About it and i thought i shifted faster than this and i knew that Faster shifts were possible and that i have been doing them for most of the cars life without any problems...
And as i said i was moron about it and in the First few thousand Km i destroyed my 2nd Gear sinchro. I Wanted to fast shift as i used to and I ended Up Grinding every 2nd gear shift and i got madder and madder and than the Sinchros died and that was it.
So i Definitely know that the SC made the shifts Slower and i needed a lot of time to Adjust to the slow shifting so i don't destroy the second set of sinchros. It must have to do with the Faster Rev of the Car helped with the SC and the Faster spinning of the engine.
So i use Grandmother Shifting now and i still get some Grind once a While when i get carried off.
I wouldn't say that Lighter flywheel eases shifting at redline only makes you work more to get a faster shift than before since the revs are falling faster and you don't want to get stuck out of Vtec if you slow shift with a lighter Flywheel.
Cheers.
I had my car NA for 40000km and had super fast Shifting On my S2000 And i shifted super fast 1-2-3-4. Maybe have Grinded the tranny 5-10 times by a small stupid mistakes...in that 40000km
Than i supercharged my S and after that i noticed that I couldn't do that fast shifting at all and i had to wait.....
I was a Moron About it and i thought i shifted faster than this and i knew that Faster shifts were possible and that i have been doing them for most of the cars life without any problems...
And as i said i was moron about it and in the First few thousand Km i destroyed my 2nd Gear sinchro. I Wanted to fast shift as i used to and I ended Up Grinding every 2nd gear shift and i got madder and madder and than the Sinchros died and that was it.
So i Definitely know that the SC made the shifts Slower and i needed a lot of time to Adjust to the slow shifting so i don't destroy the second set of sinchros. It must have to do with the Faster Rev of the Car helped with the SC and the Faster spinning of the engine.
So i use Grandmother Shifting now and i still get some Grind once a While when i get carried off.
I wouldn't say that Lighter flywheel eases shifting at redline only makes you work more to get a faster shift than before since the revs are falling faster and you don't want to get stuck out of Vtec if you slow shift with a lighter Flywheel.
Cheers.
Joined: Feb 2004
Posts: 1,491
Likes: 11
From: Pensacola
Originally Posted by stena,Apr 9 2007, 05:05 AM
Hi Guys..
I had my car NA for 40000km and had super fast Shifting On my S2000 And i shifted super fast 1-2-3-4. Maybe have Grinded the tranny 5-10 times by a small stupid mistakes...in that 40000km
Than i supercharged my S and after that i noticed that I couldn't do that fast shifting at all and i had to wait.....
I was a Moron About it and i thought i shifted faster than this and i knew that Faster shifts were possible and that i have been doing them for most of the cars life without any problems...
And as i said i was moron about it and in the First few thousand Km i destroyed my 2nd Gear sinchro. I Wanted to fast shift as i used to and I ended Up Grinding every 2nd gear shift and i got madder and madder and than the Sinchros died and that was it.
So i Definitely know that the SC made the shifts Slower and i needed a lot of time to Adjust to the slow shifting so i don't destroy the second set of sinchros. It must have to do with the Faster Rev of the Car helped with the SC and the Faster spinning of the engine.
So i use Grandmother Shifting now and i still get some Grind once a While when i get carried off.
I wouldn't say that Lighter flywheel eases shifting at redline only makes you work more to get a faster shift than before since the revs are falling faster and you don't want to get stuck out of Vtec if you slow shift with a lighter Flywheel.
Cheers.
I had my car NA for 40000km and had super fast Shifting On my S2000 And i shifted super fast 1-2-3-4. Maybe have Grinded the tranny 5-10 times by a small stupid mistakes...in that 40000km
Than i supercharged my S and after that i noticed that I couldn't do that fast shifting at all and i had to wait.....
I was a Moron About it and i thought i shifted faster than this and i knew that Faster shifts were possible and that i have been doing them for most of the cars life without any problems...
And as i said i was moron about it and in the First few thousand Km i destroyed my 2nd Gear sinchro. I Wanted to fast shift as i used to and I ended Up Grinding every 2nd gear shift and i got madder and madder and than the Sinchros died and that was it.
So i Definitely know that the SC made the shifts Slower and i needed a lot of time to Adjust to the slow shifting so i don't destroy the second set of sinchros. It must have to do with the Faster Rev of the Car helped with the SC and the Faster spinning of the engine.
So i use Grandmother Shifting now and i still get some Grind once a While when i get carried off.
I wouldn't say that Lighter flywheel eases shifting at redline only makes you work more to get a faster shift than before since the revs are falling faster and you don't want to get stuck out of Vtec if you slow shift with a lighter Flywheel.
Cheers.
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From: Bethesda, MD
Originally Posted by hecash,Apr 9 2007, 03:46 AM
Absolutely..........I'm not going to get into how many trannys I put into my AP1 and I just had my AP2 done under warranty. It seems that with this gearbox you either get one that's silky smooth or a Captain Crunch job. I now have my first silky gearbox due to a super technician at Pauly Honda in Libertyville, IL named Aaron. Thank you Aaron.
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Posts: 7,087
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From: Dry Branch
Originally Posted by slipstream444,Apr 9 2007, 07:25 AM
It's likely tied to a combination of things to include greater stress on the transmission and fluid, and a slight change in the timing due to the difference in rev characteristics.
JD Power's statistics prove beyond any doubt that our transmissions are not inherently flawed. Claims and experience of a few don't change that in any way. A few owners break multiple transmissions while most have no problems, or at most an occasional grind going into second (usually when the transmission is cold). Since only a few have repeated faliures that is a statistic too, and it clearly points to the most likely cause of the failures.
Blame the car and ignore the real cause of the "problem," and you too can go through one transmisison after another.
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From: Dry Branch
Originally Posted by hecash,Apr 9 2007, 06:46 AM
Absolutely..........I'm not going to get into how many trannys I put into my AP1 and I just had my AP2 done under warranty. It seems that with this gearbox you either get one that's silky smooth or a Captain Crunch job. I now have my first silky gearbox due to a super technician at Pauly Honda in Libertyville, IL named Aaron. Thank you Aaron.
If one driver has repeated failures of a part that has a good record for reliability, what are we to conclude? The simple fact of the matter is that even though our cars and transmisisons have a good reliability record, you just got a series of bad transmissions. We had something similar happen last year with our Miata. Three consecutive alternators failed a week or two after having been installed on the car, and I was just certain that we were overlooking some problem that was making the alternators blow. As it turned out, we weren't overlooking anything. In spite of the fact that Miata alternators have a good reliability record, we got three defective units in a row.
Anyway, to determine the reliability of this car people need to look beyond what they see in the threads here on S2kI. This is a great resource, but it's easy to get the wrong impression. I worried about my clutch and diff for a while, because everyone who posted in every thread I was following was having clutch and diff problems.
It's easy to let this stuff make one paranoid, but the statistics don't support the paranoia. Neither does a single driver who has seen multiple failures; Statistically that's just an outlier.