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Q for anyone running an aluminium flywheel

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So I'm out for a drive tonight because it's (just) warm enough and I've been jonesing. I'm in the mood to try to quantify the differences between the engine as it is, vs how it was before.

The most obvious is the lack of blue smoke...

I notice that the car revs up much faster, but it also doesn't seem as torquey from a standing start - before I could set off by lifting the clutch with my foot off the accelerator. Now I have to rev it to get it to go.

So my question is simple - does this fit with observed behaviour when installing an aluminium flywheel, or is it a different change that's causing this?
 
Alan,

I was told by three other TR6 owners who switched to aluminum flywheels that I should expect to find what you state above.

On the other hand, they felt it was worth getting used to after about an hour of city driving for the quicker rev factor and smoothness when shifting. They all said that they felt that the car gained power by making the swap, though two had no other modifications made at the time.

The other car was done up pretty well with compression, cam and breathing & fuel upgrades, so he couldn't tell how much the flywheel attributed to his overall gain.
 
Oh it's worth it. This thing spins up to 6k faster than I ever thought possible.

I figured that was what it was, I just wanted to make sure.
 
Alan,

That is typical of a lighter flywheel. Simply put there is less stored energy. The revs will drop off quicker on gear changes and a REALLY light flywheel can make the car tricky to get moving from a stop. Light flywheels usually tend to be noisier under deceleration. Does wonders for acceleration though, especially in the first couple of gears.
 
Alan,

Yep, you'll have to rev it up a little more than when you would have an OEM flywheel. In my opinion, an alloy flywheel is one of the best upgrades that you can do to these motors. Nobody will call it a TRactor motor again. :smile:
 
They get in mine and thoughts of TRactors are the last thing going through their head. It scoots along rather well now...
 
Alan,

It would be just the opposite. The lighter flywheel allows the engine from a low rpm to rev up faster. The original 32lb lump requires more energy to spin, slowing acceleration. I have not noticed any such performance loss. The heavy flywheel stores energy when spinning fast which may help on a power shift. You should feel a lightness between shifts & better throttle response.
 
Mitch, you must have misunderstood my last comment. I wasn't trying to say that there was a performance loss - quite the contrary in fact. But then it's had a few other things done to help it out too.
 
Alan, My bad. I read it as a loss of low end grunt. Many people have posted comments that an aluminm flywheel is responsable for easy stalling, difficult off clutch starts and torque loss. I really have never expeirianced any of that. I do realize that the blower will mask torque loss but when I accelerate normaly from a start no boost is used.
The advantage of the lighter flywheel diminishes as rpm's build & even more as you rise in gears. But I also found an ease when downshifting almost as if the trany isn't fighting the additional mass. Believe me, even with the loss of almost 20lbs from the flywhell, the crank is still an enormous amount of rotating inertia. I was amazed when I lifted the crank in my rebuild. Even the machine shop had a laugh.
 
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