Aluminum flywheel

[Clay Pitkin]

Just curious

Is anybody running a aluminum flywheel. Do you like it? Have you had issues with it?

TIA,

Clay

[RichFox]

I have run an aluminum flywheel. Didn't see any advantage

[Milwaukee Midget]

The advantages an aluminum flywheel brings to the equation are minimal in LSR - less inertia to overcome for acceleration is the performance advantage. 

They are usually an extruded product for racing - clearly built to a higher tolerance than the stock piece.  I know mine was a heck of a lot better balanced than the iron one it replaced, and only required minimal material removal to balance the entire reciprocating assembly.

If you're running the short course with a small engine and no push, the slight acceleration advantage might be of help.

[gearheadeh]

Just curious

Is anybody running a aluminum flywheel. Do you like it? Have you had issues with it?

TIA,

Clay

I have always felt that it might be advantageous to explore the lightest weight possible in all rotating assemblies from the crank/flywheel on down to the rims and tires.
The sole reason for this would be to see if once the tires started to slip at high speed, feathering  the throttle might result in the traction coming back quicker than trying to overcome the inertia of heavy spinning parts!

[4-barrel Mike]

And of course, your regular "stock" flywheel is probably illegal:

3.O FLYWHEELS, FLYWHEEL SHIELDS and BELLHOUSINGS: "...Flywheels: No cast iron/cast aluminum flywheels shall be permitted."

 

Mike

[RansomT]

I've got one on my blower car and I hate it ... forget trying to pull out without spin

[Clay Pitkin]

And of course, your regular "stock" flywheel is probably illegal:

3.O FLYWHEELS, FLYWHEEL SHIELDS and BELLHOUSINGS: "...Flywheels: No cast iron/cast aluminum flywheels shall be permitted."

 

Mike

Ok, they say when in doubt ask how (Grin)

How do you tell its a cast iron flywheel?
I was under the impression that cast iron flywheels are on older vintage vehicles.

This particular flywheel came off a late 80's early 90's Suzuki Swift (Geo metro)

Its not aluminum, I know that.

What I am looking at is this: I do run the short course, with very little push, and run a two stroke snowmobile engine for power. Is it better to lighten the flywheel I have, (if its not cast iron) or go with a aluminum  flywheel?

I have been told yes, it will spool quicker with a lightened flywheel or aluminum, but I have also been told that you want the inertia there for rotating mass.

I don't want to give the idea that I am disagreeing with anyone just trying to do research on what is/what works best and what doesn't.

TIA
Clay


 

[RichFox]

It' likely cast iron. Is it machined every where? Or is the back of the flywheel kind of rough in places. Kind of like the outside of a cast iron block? If you are running a small motor like a Geo comes with, I would think you would want a steel flywheel. I don't know if cast steel is legal. Mine is billet.

[Milwaukee Midget]

I have been told yes, it will spool quicker with a lightened flywheel or aluminum, but I have also been told that you want the inertia there for rotating mass.


 

A good point - you want the inertia to carry the assembly through the compression stroke, but I imagine if it's a snowmobile engine, your engine is likely a two-stroke, probably not running nearly as much compression as a typical four stroke, you've just come off of a power stroke, and it might not need the added inertia.

Here's what I'm thinking . . .

I expect you'll be turning some pretty high revs, so the less mass you have, the higher up the rev range you'll be able to turn without developing potentially ugly crank vibrations.

As to whether it's aluminum or steel, I don't think it's as important in your case as is keeping the mass down and making sure it's well balanced with the rest of the engine and clutch assembly.

I'll admit, my experience is limited, but I was shifting at 9200 with a 3 main block design that goes back to WWII, a very lightweight balanced assembly and an aluminum flywheel, and it ran smooth as glass.

Do you know Tom Donnely, the guy who ran the SAAB Sonnet?  That's a two stroke - He's in Fort Dodge, Iowa, and he was turning some scary revs with that little 3 cylinder.  I'd be tempted to search him out and ask.

Looking forward to seeing what you're up to with that little monster.   

[Interested Observer]

The sole reason for this would be to see if once the tires started to slip at high speed, feathering  the throttle might result in the traction coming back quicker than trying to overcome the inertia of heavy spinning parts!

Conversely, a heavy drivetrain would be less likely, in the first place, to spin the tires over every little bump or slick spot.  Hillclimbers love big flywheels.

A heavy flywheel may slow down gear shifting but a small bore racer is going to spend a lot more time in gear than between them. 

It is probably more important to worry about how a different flywheel/clutch affects the torsional vibration of the crank and pulley assembly. 

[Clay Pitkin]

Well as determined my OEM flywheel is cast. I found an online source for aluminum flywheel for the Geo, seems like  alot of $$$ but hey its only money right......

They do not make a steel flywheel for the Geo.

So.... I have once choice, gotta get the aluminum flywheel.

Just for FYI, yes it is a two stroke snowmobile engine. Gonna be interesting to see how it performs.

TIA
Clay

[kiwi belly tank]

The way easy way to tell steel from cast is to tap on it with a hammer, a steel one will ring like a bell. If it doesn't it's either cast or a cracked steel one.
  Sid.

[manta22]

Sid;

The same trick works on a crankshaft.

Regards, Neil  Tucson, AZ