TR2/3/3A Alloy flywheel

[Snowkilts]

I've seen alloy steel flywheels for TRs being sold at a couple of places, including here: https://www.bpnorthwest.com/alloy-light-flywheel-tr2-tr3-tr4-tr4a.html

Similar weight and pricing as aluminum. Has anybody tried these? Any thoughts?

 

[karls59tr]

While on the subject...how would a lightened flywheel affect driveability for everyday driving?

 

[malbaby]

IMHO....I would keep to the original steel flywheel providing the ring gear is OK....alloy can be problematical.
I lightened mine down to about 22lbs if I remember correctly, together with a full balance of all rotating engine/clutch components.
Engine accelerator response is much better.

 

[Snowkilts]

alloy can be problematical

How so?

 

[TRMark]

How so?

Curious about that also. I have seen comments about problems with aluminum flywheels but not steel. How light is too light for street use.

 

[malbaby]

Steel much stronger than alloy... clutch exerts a lot of pressure on the flywheel.

 

[bobhustead]

One of the things a flywheel provides is momentum (smooths thing out between the bangs). These cars don't want to idle smoothly in the first place. I say stick with steel.
Bob

 

[Snowkilts]

Steel much stronger than alloy... clutch exerts a lot of pressure on the flywheel.

The part I'm asking about is an aftermarket alloy steel flywheel. As compared to aftermarket aluminum flywheel (with steel wear insert) which seems widely available, or the stock flywheel which I assume is cast iron.

 

[davmar1960]

If you use the alloy flywheel does the clutch mating surface need to be scuffed ? It is very slick

 

[Hamish Racing]

I have a lightweight steel flywheel. You can see it in this video at around 2:30+

I also have a hot cam. It’s still very drivable on the road. See here

It has a great acceleration pickup.

Lightweight Steel Flywheel Assembly TR2-4A, Morgan +4 etc - Triumph Special Tuning

Lightweight steel flywheel assembly 4 cyl TR engine applications. Improves throttle response enormously, without unduly affecting tick over. Approx 5.5kg Requires diaphragm clutch to be fitted.

triumphspecialtuning.com

 

[davmar1960]

Thank you

 

[TR-3rg]

Hi,

I have a 10 pound Firenze aluminum flywheel in my 1960 TR-3a. I love it. Its factory drilled for a TR-3 and the smaller TR-4a pressure plate. The metal insert is for a TR -4 a disc. It works fine with either pressure plate. In my opinion, this is what the car should have had from the factory.

I do have a recurved distributer with 12 initial and 32 total. Starts at 1600, all in by 2400. That really helps the low end drivability. I dont know what its like with a stock Lucas distributer.

Another benefit, the engine shuts off, no dieseling.

Good luck, Roy

 

[groupdeville]

Sadly, the makers of the lightweight alloy steel flywheels do not seem to produce them with drillings for the TR2/TR3 coil-spring pressure plate, for those of us who prefer the near-bulletproof reliability of the earlier design. So, the flywheel choice then becomes between having a stock TR2/early TR3 flywheel lightened down to 16 or 17 pounds or the aluminum Fidanza unit.

 

[TR-3rg]

My Fidanza flywheel was drilled for both pressures plates. The steel friction surface is for the smaller TR4a disc. I rant he stock tr-3a pressure plate pressureand TR-4a disc for a couple of years. I now have theTR-4a / TR-6 pressure plate because I went to the Supra 5 sp conversion.

Fidanaza lists as the "1954 -1965 TR-4 / 1965-1966 TR4a" flywheel. I think its part number 172441. Just double check be fore ordering!

Roy