Harmonic Dampeners

[IronFreak]

Current build I'm having some concerns about the harmonic dampener not doing its job at higher rpms.....where it'll be living most the time. I'm running a billet ASP flywheel with a 7.25" quartermaster triple disc. pretty light. Done some research but there isn't much info specific to the m20 motors, lots on the s/m52 s/m54 stuff. just not sure that applicable with my situation.

Any input would help. right now I'm at the conclusion or just replacing the stock one every year. VAC sells an ATI but I've read several thread over on BFC and they don't seem to be that great. maybe I'm wrong......plus I'm not willing to dump $900 to "try" it out.

Thanks

[djjerme]

What are you thinking of shifting at?

Many PRO3 cars will shift north of 6500 - and all are running stock dampener.

If you are running above 7000, harmonic vibrations are the least of your worries - your valve train will become the weak point.

[IronFreak]

What are you thinking of shifting at?

Many PRO3 cars will shift north of 6500 - and all are running stock dampener.

If you are running above 7000, harmonic vibrations are the least of your worries - your valve train will become the weak point.

it'll most likely be set between 6500-7000 so that answers my question.

Appreciate it!

[nando]

you don't need a special harmonic damper on an M20, even spinning well north of 7k. 8k+ sure, but a $900 dampener will be the least of your investments.

[IronFreak]

you don't need a special harmonic damper on an M20, even spinning well north of 7k. 8k+ sure, but a $900 dampener will be the least of your investments.

I won't be spinning that high, my concern was that my new flywheel/clutch setup will weigh roughly 10-11lbs. total. I'll be losing some dampening effect back there and wanted to make sure the front dampener could still do its job.

[djjerme]

The engine is internally balanced - so that is really not an issue.

[IronFreak]

I have just been reading up on harmonic distortion etc, I wouldn't be changing the front dampener but I just wasn't sure how much effect removing a lot of weight from the back would have. I know some, but not enough about these motors to make a definitive answer, hence why I posed the question. Thanks for you input though, its much appreciated.

[Nisse Järnet]

I revved between 7k and 7500rpm all day long for 5 years with old stock damper and both lightened M20 and lightened M30 clutch setup with no problems at all.
Not much track time but i liked to rev it alot on the street :D

[burkey001]

I have been running the VAC damper for 2 year+ on a track only, fully built S50 euro. I have had no problems with it.

What is supposed to be the 'issues' with it?

Recently saw an S50 with a solid crank pulley, full light weight (i.e. no damper) and it eats chain tensioner guides in 3 runs.... so yes. you need something you're happy with

[nando]

M20 isn't an S50..

[digger]

i bought a new M20 vibration damper, it was pretty exxy though much much cheaper than ATI not that i enquired with ATI for a M20 specific one....i did this because there is not much long term data on m20's with long stroke cranks revving high so thought it was worth the investment and rubber subject to heat and stress above what it was designed for can only have a finite life.

Still i don't think i will need to be spending much time past 7k by design