Originally posted by PA 3L SVT: [b]UDP bad. DMD good.
Why is that Jason? The UDP are on the new motor in my car. [/b]
Long story short: A UDP without any damper (like all of them) allow the crank to vibrate leading to bearing wear, etc. The DMD (Dual Mode Damper) has 2 dampers to reduce/eliminate the vibrations at two frequencies. It's a Ford OEM upgrade found on European Duratecs. The stock pulley has one damper (which is better than none, but not optimal for an engine that revs to 7k).
I'm quite convinced that my STOCK motor died as the result of "crank harmonics (vibrations)" thrashing a bearing. It won't blow up in a day, but long term prognosis could be bad.
Ford spent a lot of money to develop the DMD. It also took a lot of convincing for the accountants to put a more expensive part on the Euro Duratec, especially one that the marketing guys really can't show off. It's also the only thing Ford has done to combat the early deaths of 2.5 Duratecs (and only in Europe to boot).
Search around for the discussions (ad nauseum) on the DMD. They'll contain a link somewhere to a site that details the detriments of UDPs on a Toyota (?) engine.
On topic: I might go to the Friday Test and Tune (9-4) at Maple Grove next weekend. $25 and the crowds should be low as many people actually have jobs to be at then. http://www.maplegroveraceway.com/fmsninfo02.htm [/b]
Thanks I'm going to look into replacing the UDP with the DMD. It makes sense to me, the UDP was on the car when I bought it and FORD just swapped the pulleys off the dead motor.
Thanks again, Brian
Brian D. Passaro -------------------- 1998 Contour SVT E0 Silver Frost #3734 of 6535 (Died 10/31/01 Reborn 02/03/02) Superchip(Removed)~Firestone Firehawks SZ50 215/45ZR17 on 17" Borbet Type T's~ASP Underdrive Pulley(Removed)~75mm Pro-Flow MAF(Removed)~Mobil One 5W-30 Tri-Synth~Resonator removed~Flowmaster DeltaFlow '40' series dual mufflers~KKM Air Filter Induction System(Removed"Lost at FORD Dealer")~2.5-inch custom cat-back exhaust system w/ reduced angle Y-joints~4-inch rolled chrome twin-tipped exhaust tips~Konig V-racing aluminum BTCC-inspired rear wing~Sylvania Blue headlamps