Aasco flywheel is here. - 986 Forum - The Community for Porsche Boxster & Cayman Owners

edevlin · 05-13-2009, 05:28 AM

Interesting stuff, I sure like learning more about our engines. In my case I have almost 3 years and 40K on my Aasco lightweight flywheel, and I love the driving experience with it, engine and car are much more responsive.

I did not think much of it at the time, but right after it was installed, it did seem to me that there was a bit more vibration comming from the engine compared to the factory flywheel, another subjective data point for the discussion.

As I said, I really like the performance of the car with the lightweight flywheel, but I must say, if I had known back then what I know now about the harmonic balancing function of the flywheel, I pretty sure I would have kept the unit stock, live and learn.....

:dance:

JAAY · 05-13-2009, 06:18 AM

Calling my Porsche buddy to see how much a stocker is. But. Why did my other go within 4k miles?

Jake Raby · 05-15-2009, 02:52 PM

Ummn, what do you think the components feel if they are screaming that way just at idle?

timothy · 05-15-2009, 03:35 PM

Just wanted to chime in and say thanks for a very informative (and civil!) discussion.

jaykay · 09-20-2009, 09:32 AM

Just curious as to whether anybody knows whether a light fly wheel could mitigate crankshaft and RMS damage by reducing the overhung weight at the back of the crankshaft. I would think the DMFW at 40 lbs, slightly unbalanced, on a slightly untrue crank could cause undue crank shaft deflection resulting in RMS damage and leaks. I would think by the time you have an RMS leak you already have engine damage.

I was thinking of a LWFW just to prevent this scenario but I am just learning about all the negatives associated with it. I have a very low mileage engine (m96) that I would like to make reliable.

What flywheel would I use to be safe? Do I need a clutch to go along with it? It is not a race car so I would like to keep it as streetable as possible. What are the risks? Will a dynamic balance problem be caused?

Thanks,

jaykay

cnavarro · 09-20-2009, 10:02 AM

It's questionable to put a lightweight flywheel on the engine without some sort of harmonic balancing to offset the loss of the dual mass flywheel. I have had many phone calls from individuals and shops alike with broken crankshafts, attributed to lightweight flywheels and it's bad enough that Porsche issued a TSB that use of a lightweight flywheel will void the warranty, likely due to harmonics I would imagine. It's been touched upon in this thread and I highly doubt that a reduction in mass would fix the RMS issue. Engines with multiple RMS failures are indicative of a larger problem - drooping of the crankshaft carrier in the crankcase.

jaykay · 09-20-2009, 10:46 PM

Thanks Charles. I was not aware of the crank carrier issue and have never seen the internals of these engines. That big heavy DMFW hanging off the end of the crank right beside the RMS got me wondering.....

I would like to keep my 2000 3.2 from ever developing problems if I can..

Take care