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Question lightweight flywheel?

Which is the best lightweight flywheel to use?

Is it recomendable?

What is stock weight of a 74 carrera flywheel 2.7 CIS?

Old 01-01-2007, 05:54 PM
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fancytown
 
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Not sure on which one to use, but if the car is to have a significant amount of street driving, don't do it. It will make the car very "annoying" to drive in any sort of stop-n-go situation. Plus, your passengers will insist you drive "solo" after shaking them up.
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Old 01-02-2007, 07:06 AM
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not a daily driver, just a weekend driver

aside from it reving faster, what do you mean by shaking them up?
Old 01-02-2007, 10:05 AM
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Quote:
Originally posted by Jay Auskalnis
Not sure on which one to use, but if the car is to have a significant amount of street driving, don't do it. It will make the car very "annoying" to drive in any sort of stop-n-go situation. Plus, your passengers will insist you drive "solo" after shaking them up.
Hi Jay:

With all due respect, installing a LWF in these cars will have little or no effect on drivability unless there are pre-existing issues with the pressure plate, clutch disc, FI or ignition timing.

We've been doing such things on these cars since 1978 with no stalling or jerking unless there were other problems.

As with anything, driver technique and skills play the biggest role regardless which flywheel/clutch is in use,...
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Old 01-02-2007, 12:24 PM
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A stock 6 bolt flat flywheel (1970-1977) weighs about 8 pounds. "About" because all I have for weighing at this weight is a bathroom scale.

For reference, on the same scale an RSR style flywheel weighed 7 pounds. An aluminum 5.5" Tilton style flywheel (with pilot bearing) weighed about 5 pounds, but you would not want to use this kind of clutch on the street.

You can do good things by being careful about which pressure plate you use:

The "aluminum" Sachs (cast iron center plate, aluminum outer housing) weighs about 8 pounds. This is what your '74 came with. The iron PP (iron outer housing) weighs about 12 pounds. You don't want one of those. And for really light weight, there is the RSR 4 pound PP, which uses an aluminum center plate with a ferrous spray coating on the wear surface.

I don't think you will have a problem running a lightened steel flywheel on the street. I ran one for years.

Now whether switching is worth the cost and effort, that is another matter entirely.

The one pound or so differencein the RSR steel flywheel all came off the all important outer inch, though, so its effect on the MOI exceeds its mere mass. Here is what a 9 bolt one looks like, but the 6 bolters are the same (some also have lightening holes between the pilot bearing and the wear surface).




Walt Fricke
Old 01-02-2007, 12:49 PM
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This is from someone who installed a lightweight flywheel on his 3.6L. As for street driving, I'm talking about stop-n-go, inner city Chicago, not getting out of 1st gear much. The throttle was a hair too sensitive, and he wished he went with a "standard" flywheel. After 15 minutes, it was "uncomfortable". I drove in the car and agree. I guess I should have clarified. For typical highway, or more "open" streets, it was ok.
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Old 01-02-2007, 01:39 PM
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My motor is already in the process of a rebuild, this is why I am asking whether is it worth it to change to a lightweight flywheel or not.

It does already have a new clutch/PP etc...

thanks for all the replies
Old 01-02-2007, 01:58 PM
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The 3.6 is another story. You are removing many many many pounds when you dump the dual mass flywheel in those cars and the motronic still thinks you have a heavy flywheel. With out chip modifications there can be stalling issues with the 3.6, I know that first hand.

Cheers
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Old 01-02-2007, 02:44 PM
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agreed dont do it

LW flywheel will make your car significantly less enjoyable even on the weekends. I have had mine for 6 months and would not do it...you want a faster car dont try to second guess the best engineers in the world buy a newer version.

Old 06-16-2008, 01:03 PM
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