Contour Enthusiasts Group Archives Forums Modifications Transaxle Flywheel

Gentlemen, gentlemen,

If the benefits of the lightened flywheel are so obvious
then why doesn't Ford manufacture these cars right that
way ? 0-60 time is something people consider when shopping
for sporty sedans.

With a lighter flywheel the car has better acceleration,
no doubt about it.
What is the downside ? Worse idle, increased vibration,
overall shorter engine life. Of course this is true for
the majority of performance mods and most people around
here interested in better acceleration only, and happy to
pay its price.

T.

I would choose the weight of the flywheel based on how much of the powerband you want to use. If your optimal powerband is 3-7K RPM, you would use a lighter flywheel than if it was 4-6K RPM. Since it is not cost-effective to change really adjust your gear ratios, those do not become a factor.

So if I was running an N/A or SC V6 setup with a broad powerband I would probably upgrade to a lightened flywheel. But if I was running a car that did not have a very flat powerband, I would probably stick with the stock flywheel since it would probably keep me in the meat of my powerband better than a lightened flywheel. Like a turbocharged four banger.

Maybe my reasoning is off, but that is my reasoning.

Maybe this will help...an article in SCC talked about effects of a 10# aluminum flywheel in a Focus with stock 22# fly...should be pretty similar for Contour.

I do not have the equation they gave but the deal is that flywheel weight is more of an issue at low rotational speeds and the benifits of lightening it are greatest in low gears and decrease in higher gears. You can calculate the net wheel HP gains (really decreased losses)...
1st gear ....equivalent to gaining 26 HP (you will feel that!)
2nd gear ...equival;ent to gaining about 9 HP
3rd................................about 5 HP
4th................................about 1 or 2 HP.
Now, when you dyno, it is in 4th gear...so it will look like little or no gain. But, if you can get traction in first with the extra power, you WILL be quicker. If you just spin wheels anyway, you will not.

What is the downside...
1) It will be harder to drive smoothly, esp off the line with more jerking. OEM carmakers do not want to build a car that makes it seem like you cannt drive!

2) faster dropping revs = good for race driver, bad for syncros (we are weak here BTW).. OEM would either need to put in stronger syncros or have a higher failure rate..neither is desireable.

3) Some strength is sacrificed. esp with aluminum. (using steel insert can make a strong al fly, just more $$)

4) More NVH

5) Less stored inertia for launch (more related to smoothness) but would require higher launch RPM to get same results in 60' times = more clutch/differential stress/wear.

Cost (in addition to smoothness) is probably part of the reason OEMs avoid light flies. But not so much cost of the flywheel (steel inserted al flies asside) Ford could have easily designed a cheap light nodualar iron fly that was even lighter than SVTs has for same money. But they would need to upgrade the clutch, differential, and syncros to meet the same durability goals. And if you buy such a fly, be prepared to do the same..ie. HD clutch, Quaife, bulldog box or late 2000+ syncros..

ATTN: If you buy a lightned flywheel make sure it is compatiable with your clutch. I went through two clutchs and then I just said [censored] it and sent the flywheel back to fidanza. If you get a solid hub clutch teamed with up with an aluminuim flywheel get ready for the racket of your life. The gear rollover is so bad you would think there are rocks rolling in your trans. At the time I had my fidanza in I didn't see much on the performance side of things. I installed everthing myself and felt that its made of good quality material its just not rough enough surface to break in a non organic clutch. It never heats the puck up enough to get it past the green period.

I have the SHO shop LW flywheel on my SVT. I LOVE it! I just can get over that BS a few posts up! LMFAO

This example of gained HP in each gear is related to the moment of inertia. It is the rate of acceleration that is improved, same with any lightened mass...this part is always better for power and less stress on the components in normal situations. However, the rate of acceleration is so poor in 3rd gear and higher, that it isn't worth that much, and if you consider the case of these decently done 3L motors, any of them will burn the tires through 1st and maybe second gear and the lightened flywheel will only make that situation worse.
I don't think that the cost justifies the gain when I look at it from that perspective. Better or easier launching is also a benefit that should help out with a more massive flywheel and may overshadow the benefits of the lightened mass.

On the subject of reliability and to forestall a full scale flame of the individual who posted about it earlier, here's a few points:
I am only going to mention that the whole dual mode damper saga was based on its ability to damp harmfull frequencies at different ranges, resonances if you will. Why is it not under consideration now? What is the end result of that process? The end result is smoothing the torque of the engine. Well the flywheel does that a lot. Also, the more massive the rotating assembly, then generally the lower the resonance point which could be designed to keep that out of the normal operational rpm range. All in all, that may contribute to longevity and any change to that may be detrimental.

warmonger

Seeing as I was dropping my trans to add the Quaife and Zetec final drive (in preparation for the Turbo), it was brain damage NOT to add the Fidanza and Centerforce DF clutch.

I want ALL the power I can get to the ground!