[SteveS]

Has anyone installed one? Seems like waste of energy to spin the heavy flywheel. I testdrove MCS and noted that shifting smoothly took much different technique than my 88 M3, as engine on MCS is slow to spin down when you get off the gas. Seems like the engine uses a lot of power to spin up, but the power is wasted when you get off the gas as you just use the brakes more than you otherwise would. The energy stored in the flywheel is only used starting from dead stop, and it hurts everywhere else. I understand the heavy weight and design (two piece with springs linking the pieces) was put in to ease strain on the under specced gearbox. This is also probably why no limited slip is offered as this would tend to focus stress on gearbox. Has anyone installed the a lighter one? How has gearbox held up if you did? How hard - how much labor, to install it? What do you think of the mod?

[chris@helix]

Funny that you would post this, We are doing one on a car today. I don't know what the stock weight is but the new one comes in @ 9lbs. I will give you a report in a few days.



All the best

Chris
helix MINIsports
helix13.com

[ezrally]

Just ran an ice (glare) trial Sunday, and the throttle hangup made slowing down a bummer.
Maybe the fly by wire has a part in this problem too besides the heavy flywheel.

[QQQ]

Quote:

Originally posted by obehave
Just wondering where there is information that the gearbox is underspec'ed. Have you read about it failing? Do you have a link to some facts? I haven't heard any of the auto-x guys complaining about it breaking.
Really just curious where this information is coming from.
Thanks

Obehave: Somewhere in this thread re quaife differential, Targa (who had a quaife dif installed on his ralley MCS) posted that he blew up first gear when exiting a slow corner. He had to swap his gearbox for a fresh one.

He also mentioned that for the Focus (which has the same Getrag gearbox as the MCS), Ford reduced 1st and 2nd gear torque by its ECU for gearbox reliability...

[Racer]

obehave - I blew a gearbox on the track and know of others as well! - Whilst they appear to be 'adequate' I'm sorry to say they are certainly not bullet proof

[QQQ]

Quote:

Originally posted by Racer
obehave - I blew a gearbox on the track and know of others as well! - Whilst they appear to be 'adequate' I'm sorry to say they are certainly not bullet proof

Racer: Did you have LSD installed or any other mods or did you break your gearbox with your S in stock condition?

Cheers,
Erwin

[SteveS]

How much? was it something a psuedo mechanic could do?

[Casey]

Not sure what the dealer would charge you for a new gearbox - but mini mania is selling them for around 5000usd though....so not cheap.

We need some stronger gearboxes if we are going to be pushing 225+hp with LSD and lightweight flywheel etc.

[minimini36]

I think there is some confusion/wrong information in this thread in regards to transmissions. First the statement that the Focus reduces torque in first and second gear applies to the European Focus RS which is a 212 hp turbo Focus. This car uses the FORD MTX-75 five speed transmission not the 6 speed Getrag used in the Focus SVT and MCS. I also think Racer's car is an MC not an MCS. Part of the reason the MCS got the 6 speed Getrag was because the 5 speed from Midland Powertrain could not take the torque. I am not sure that the LSD would actually increase the load on the transmission. Unless you drop the clutch you can apply full power to the transmission on a straight road with good traction and most of use have done this many times. I will agree it is hard to do this in a turn. I think the shock load on the transmission would be much worse if one wheel was spinning and suddenly hooked up putting a lot of shock on the transmission. The LSD should help prevent this. I have not looked at the other thread recently to find out if Targa learned what failed in his transmission. Was it a failure of the gears themselves or a failure to stay selected in first gear? When the failure mode is determined we may know if the transmission is not strong enough or was it a defective part. I had a failure in an another car and it was the selector fork that failed and kept me from selecting one gear. It was just a defective part.
Now return to the flywheel discussion. In some cases if it is too light as is the case in some racecars it is harder to get the car rolling. This is because it has stored energy to get you going. Once the clutch is fully engaged the car will accelerate faster since less power is wasted accelerating the flywheel. You can see the same effect on a chassis dyno that measures the power by timing the acceleration of the rollers that have a known mass. The horsepower reading will be higher if you use fourth gear instead of third gear since the engine speed will not be accelerating as rapidly and will require less power. In fact one of the cold air intake dyno charts that has appeared on the web had exactly this situation. The base run was in third gear, the first run with the mod was also in third and to a higher rpm and the final run with the mod was in fourth gear. Guess which one showed the most horsepower. It was the run in fourth gear.
In the discussion about light weight tires and wheels it would be interesting to see dyno runs in say second, third and fourth gears with light and heavy wheels to see the gains made.
If you made it this far thanks for reading my ramblings.
Now return to the original light flywheels discussion.

[gt4pete]

Another concern in installing a lightweight flywheel is the clutch. Cars with dual-mass flywheels often do not have any relief valving on the clutch. When the clutch is popped in a normal car, there is a relief valve which controls the amount of pressure in the slave cylinder. This prevents the clutch hydraulics from blowing a seal. Installing a convetional lightweight flywheel may require installation of such a system to protect the clutch cylinder from breaking.

I have an S myself and, in addition to other performance mods I'm considering, I'm thinking about lighter weight wheels, tires, flywheel, LSD, etc. But I'm holding off to insure that precautions like this are addressed before I install anything. I haven't even done intake or exhaust because everything is going to have an effect on the overall balance of the car and motor (EMS reprogram will be last of course). So I'm just saving up and waiting to see what proves to be both reliable and powerful.

It's hard to wait patiently. But to get the best, you gotta be willing to hold out.

[Racer]

Quote:

Originally posted by minimini36
I also think Racer's car is an MC not an MCS. Part of the reason the MCS got the 6 speed Getrag was because the 5 speed from Midland Powertrain could not take the torque

Correct

[jlm]

I posted in the Quaife thread about the flywheel; suffice it to say:

Get the BMP lightweight flywheel; it is a quality item and works. And you lose 17 lbs of ugly rotating inertia that rotates at engine speed. From the point of view of rotational inertia, it is the equivalent of saving 17 lbs on all of your wheels!

I tried out a prototype/first edition and can report it is the right thing; if you are going to do the lsd, do the flywheel.

[Mardav]

O.K. here's my 2cents (halfpenny?) on the flywheel issue. Many moons ago when I raced dragsters (B gas rails mostly) we always installed very heavy flywheels to help lower our E.T.s, and we flew, but these things were really hard to stop (even with the parachutes. Then, when I started racing SCCA, FIA, Trans Am, and IMSA, we were making the flywheels as light as possible to achieve the quick revving we needed and to enhance the engine breaking when doubling down into the turns, but these cars were hard to get rolling; first gear was always a bear. Sooooo once you decide on the type of driving you're after you can adjust accordingly with the changes you make. I have found on street cars that sometimes just balancing the clutch flywheel ass'y can make a huge difference(especially on cars with rough off the line performance)and typically a small amount of material is removed during this process (usually 1/2 to 2 lbs).

[Mardav]

Obehave:
I was just thinking...you might want to contact someone who has changed over their flywheel to see if you can get a hold of the old OEM one. Then you could take it in to a machine shop with auto experience ('race'shop) to see if they could lighten the wheel just a small amount like you are talking about (10-15% maybe) and balance it. I believe you might get exactly what you are looking for! However, that being said, I have no personal experience with this kind of 'dual mass' flywheel so I am somewhat uncomfortable giving any advice. Take it for what it's worth!

[ezrally]

Quote:

Originally posted by obehave
Thanks that's kind of what I was trying to find out. Iused lighter flywheels on some of my street performance vehicles in the past. But they were only maybe 15% lighter than stock. I have no idea about these dual mass flywheels.
I would like to see quicker drop at lift and a little edge in acceleration. I would only be doing street driving.

Thats the reason I had a hell of a time slowing down @ the ice trial/race I went to last weekend...
I thought something was wrong w my driving and made it harder than the last FWD car I drove (SAABs).

[99mini]

i've heard 2 things about lite flywheels recently:

- a mechanic told me if you're driving into a strong gusty headwind, the car with the lite flywheel will feel more buffeting

- i read an ad over xmas (by centerforce?) promoting their lite flywheels, saying that if a flywheel is lightened too much, on fast acceleration the engine can lose too many revs between shifts and fall out of its powerband.

[jlm]

check this out:
http://www.eng-tips.com/viewthread.c...=71&sqid=41609

I started a thread about the dual mass flywheel function and there have been a few responses.

the "tizz in neutral" seems right on.

[SteveS]

LuK which makes dual mass flywheel explains that the if a dual mass flywheel is used, the clutch is typically solid - without the springs in clutch hub to take up the shock. The springs are in the dual mass flywheel. Eliminating dual mass without changing out clutch to get one having springs in the hub is not recommended as there is nothing in drivetrain to dampen out the shocks. This is what I'm afraid of. Longevity likely to suffer, so if it is very labor intensive to r&r clutch/trans, and if parts are very costly, the performance increase may not warrant the change.

I wonder if the producers of the aftermarket flywheels have analyzed the issue from the standpoint of NVH (noise, vibration and harmonics) to assess the shock loads and vibration consequences to the rest of the drive train.

[minigood]

Part of the slow rev reduction when upshifting is due to ECU programming. It is an annoyance, but it is programmed in to reduce exhaust emissions.

[Grinder]

ummmm, how do higher revs = less emmisions?