Without the elastomer within the dual mass flywheel to help quell vibrations, the ATI Super Damper makes a whole lot of sense.
Does the reduced rotational mass help in the same way as a flywheel? What other pro's/con's are realized from this type of device - what is currently being used on our cars? Thank you
The flywheel has a much larger diameter; its [ame="http://en.wikipedia.org/wiki/Moment_of_inertia"]moment of inertia [/ame]is greater than the small diameter of the crankshaft vibration damper. A reduction in weight for the crankshaft pulley has much less of an impact in terms of the energy required to rotate it than the same amount of weight reduction at the perimeter of a larger diameter flywheel. These are the OEM dampers used on the R53, early model on the left and late model on the right. To get a better understanding of a damper’s role, download this article and print, it will take more than a few readings to sink in. http://www.bhjdynamics.com/downloads/pdf/tech/BHJDynamics_Damper_Info.pdf Benefits of a damper on the end of the crankshaft are not limited to relieving stresses on the crankshaft itself, vibrations and stop/start forces are transmitted through the camshaft drive chain to the sprocket accelerating tooth wear, and to the camshaft; in extreme instances these vibrations can alter valve timing. One benefit of the Super Damper over the OEM damper is increased damping range; the OEM damper was tuned for the stock range of power output, when output is increased with a reduction pulley, greater force is applied to the crankshaft during cylinder combustion, and when increasing the rev limit another factor outside the OE tuning range has been created.
That is very interesting - thank you! Can you notice its effects through the entire range? From the diagram it looks like it exponentially improves function at high RPM.
I have my ATI Super Damper now installed and the engine runs much smoother than with the M7 2% Crank Pulley I had previously installed.
Thanks for the info, please do share any other impressions you may have as you drive your car more. Sent from my iPhone using Tapatalk
ATI Super Damper working great. I'm still experiencing some belt slip but I don't figure it has anything to do with the Crank Pulley now. Good product and a breeze to install.
Did your OEM damper fail or did you just replace it for good measure? This does seem to be a very good product and I am looking for an excuse to get one. Theoretically, this pulley at 1% larger than OEM will tighten your existing belt, unless your tensioner or belt are too far gone. If you replaced an even larger after market pulley, then of course, you should expect a more loose belt. Just get a new Napa/Gates 060535 belt and check that tensioner.
Tell us why you suspect belt slip and your hardware details please, including the brand, version, and material of the supercharger pulley.
Two pulleys changed from stock two years ago - 2% Crank pulley and the "Alta"nator pulley. I liked the increase in boost to my stock JCW 11% pulley but started experiencing vibration at idle and occasional belt slippage. ATI Super damper fixed the vibration issue, but belt slippage issue still bothers me, particularly on cold mornings. I guess it has to be the "Alta"nator pulley, but several have told me it has always been the SC pulley. I'm planning on changing the SC pulley to a 15% when I buy a head for the engine so that may solve the issue of the squeaking. I consistently have 1 hole showing on the tensioner and the belt (JCW stock belt) seems in good shape.
1. Ok, so your new damper did loosen the belt. As you moved from a 2% to a 1% oversize. 2. How old is your JCW belt? If it has had a long or hard life the rubber may be a bit hard and more likely to slip/squeal even if it looks good. 3. Go get that new belt and be slip free.
Thinking about belts, I recall that the Napa 060535 was quite a snug fit with a 15% SC pulley. Some quick rough math indicates that a 1% oversize crank pulley requires ~2mm more belt travel. So, does anyone know if the ATI 1% oversized Super Damper and a 15% SC pulley can work with the Napa 060535 belt? Way or K, since you guys have the most experience with this product..
The 535 continues to be the correct size, in fact there is more tension on a OE Conti belt with stock pulley as a point of reference. A 535 even fits a JCW and ATI Super Damper pulley combo.