lighter flywheel

[PowerRam348]

i'm wondering if i can have my stock flywheel lightened a couple pounds with no ill side effects, or, should i buy a lighter performance one.

[4doorciv]

I would rather buy a performance myself, instead of lightening my oem flywheel. Some others may say different though. With the km132 transmission, it is compatible with the Dsm fwd turbo flywheel that has a remarkable amount of aftermarket support. Fidanza being one of em has replacable friction surfaces that are like 40-50 per replacement plate. Vs buying a new one it saves cash. If there isn't much aftermarket support, I would contact a local or reputable machine shop about lightening the oem one.

[LSR Mike]

problem with lightening one is it propensity to crack even in stock form. after a few years racing I found a hairline crack in my cast iron unit. I replaced it with the Fidanza Aluminum 161261 Conquest flywheel. ~$300

[pennyman1]

I have run a lightened stock flywheel in my 1980 for over 20 years and have no problems at all with it, and I have used it as a truck before I redid it. It all depends on how you drive and how you care for your truck. I do agree with LSR Mike about not using a lightened flywheel for land speed racing - that saves you nothing. I am seriously considering the fwd dsm flywheel to replace it because it is so much lighter that I could ever get a stock one safely. The B2600 mazda site has a section on lightening flywheels - read and decide.

[PowerRam348]

i'm not looking to race this. just want to be able to build RPM's a little quicker when i get on the freeway. i only want to remove a pound or two at the most of metal from the flywheel. or, is that worth even doing?

[4doorciv]

Well the thing with light flywheels, you'll notice a quicker response in accelleration as there is less rotating mass. However with less rotating mass, the inertia to keep it spinning isn't as great. In other words, you'll get less gas milage. Gotta stay on the gas pedal to keep a constant speed for longer peiods of time.

[pennyman1]

That is true if there is a significant weight reduction - a few pounds will not affect it that much to be noticed. What you will notice is the quicker spinup off the line, especially with a 2.6 with balance shafts. Now if you go to a 8 to 10 pound flywheel then you will notice the quick drop off of rpms, but it also can save you on brakes with less push on decel.

[PowerRam348]

thanks for the info guys. it helps a lot.

[Acuta73]

As always, good info. May look into it, myself. Mine still accelerates like a 4x4, a bit more pep wouldn't hurt my feelings any.

Would the aluminum version greatly impact my ability to pull stumps and pull-out a heavy load (like a boat)? If the inertia is > than the HP/throttle response gain, I call it a draw and stick with stock. How would it effect clutch longevity?

[l.k.]

i learned something else today...nice thread...few post but great info. So its all in what you want out of the flywheel..hmmmm. never knew any of that...

thanks to all of those who posted..

Maybe this could be a sticky...im sure it will grow with time and more input will be added.

[4doorciv]

Flywheel affecting longevity of the clutch, I'm not sure about it. I haven't heard of any downsides affecting longevity. Only the fuel milage. With towing, I'm not sure. I helped pull some flex plates out of the chevy hd vans turned into shuttle busses and thoughs are pretty heavy also. Almost like an authentic flywheel for manuals.

[Ram50Man]

hmm... a lighter flywheel? i never knew that made a difference. Im going to have to look into this.

[Rahtid]

you can take about 10-12lbs off the stock flywheel

[camoit]

Lighter fly wheel = quick rpm increase = low ET. Drag racing is a must. But they can be harder on the clutch. It allows for more pounding of the mortas springs, hub and splines. (the little springs you see on the clutch) Each time a cylinder fires there is a slap of torque and power to the crank. That is transfered to the flywheel. The heaver the fly wheel the more it reduces that slap of power into the power train.

[Acuta73]

The reason for my questions is:

A heavier flywheel acts a bit like a gyro and maintains your RPM between shifts. RPM gain is faster, but so is fall-off. When pulling a load (trailer or just a bunch of crap in the bed) you may have issues down-shifting a grade because your RPM fall-off may be too fast to maintain a gear range. Theoretically it could leave you pulling a hill in first gear because you can't hit second fast enough to not bog the engine into a stall. If you have ever driven a crash-box tranny, you could manually keep your RPM up, but I'm betting this would play hell on your brass.

Good info, Camoit. Didn't ever think of it from that perspective.

[4doorciv]

Springs also can have a tendancy to jump out. I seen a few of em, but I doubt they'll happen on the mightymax or ram 50.

[tektic]

So I just spent $105 to add a pilot bearing hole to a fwd DSM flywheel. I dont have a station flywheel to compare it to but the starter plates seem very different as far as starter location goes. Can anyone confirm the fwd DSM flywheel works with a wide block and station transmission?

[pennyman1]

the issue is what the flywheel you used came off of. The fwd dsm flywheels are for narrow block motors, and the 4g64 is a wide block motor and takes a far different flywheel in diameter. You need a flywheel from a starquest or 6 bolt truck 2.6 / 2.4 g54b / 4g64 motor.

[tektic]

I was afraid of that. So I have one for sale I guess. For anyone looking for a narrow block x(

[pennyman1]

Here is a link for the right flywheel: https://www.ebay.com/itm/Clutch-Flyw...53.m1438.l2649

[tektic]

Thanks. I would use a station clutch and pressure plate with this?

[tektic]

I'm going to be making over 330hp

[geezer101]

Good power to weight ratio. It will give most cars a run for their money. I think you'll be o.k. using a lightened flywheel in your truck as it only weighs a touch under 1200 kgs. Will you do the balance shaft delete as well? Expect snappy throttle response...

[tektic]

Is there a difference between a mighty max flywheel and a Starion flywheel?

[pennyman1]

No- they are the same motor (2.6) other than size of clutch - get the 88-89 intercooled flywheel - it is 240 mm vs 225 for the truck one. Overall diameter of the clutch is the same, just the clutch disc size is different