when putting an UDP like AF/X, and unorthodox that dont have a harmonic dampener in a daily driver(41k miles, light mods, CAI, exhaust, headers...), do i have to worry about the crank or crank bearings crapping out?

thanks

That is a fear most shops tend to spread on our cars (ignorance), they associate Eclipses/Talons to 4G63 (Turbo Engines) wich DO have harmonic dampers, don't worry slap it on and you will be fine.

>That is a fear most shops tend to spread on our cars
>(ignorance), they associate Eclipses/Talons to 4G63 (Turbo
>Engines) wich DO have harmonic dampers, don't worry slap it
>on and you will be fine.

Fear?? Fear has nothing to do with it.

Our cars do have a harmonic damper.. what do you think that balanced pulley w/inertia ring is on the end of the crank?

Personally i'm not running and underdrive pulley.. it's 5hp.. that's like .3psi ;-)

Ounce of prevention worth a pound of cure.. no one has proven either way whether or not we need them. I see spun rod bearings and so forth and decided i'm not goin to chance it.

Basically if your making big HP, then use one.. if your still close to stock (+25hp) then use an underdrive..

again.. personally.. 5hp is neither here nor there.. i'd rather find somewhere else to make up the gain.

ttyl

WheatKing

Basically if your making big HP, then use one.. if your still close to stock (+25hp) then use an underdrive..

I'm confused so are you saying use it if you are stock or don't ?

he is saying that if your still NA its a good little mod to pick up a few ponies, but if your turbo dont worry about putting one on because its just a little gain with too much to worry about.

Ive had mine on for 6 months and no problems

But if I was turbo'd I would remove it

??? I thought it was a simple, worry free mod. I thought there were guys running the afx udp and turbo.

Actually I've heard that turbos get more Hp out of the UDP, like 10-14hp instead of the 6-10hp for NA apps! Also, isnt the harmonic part on the 4G a little more neccesary than on our 420A. The USP uses the stock dampener if I remember correctly its just like a washer piece or something, but I could be wrong.

The dampner is designed into the stock pulley, its the rubber oring etc. that is in the middle section of the pulley, our engines are pretty well balanced though so its not really a big deal. If we were reving to 10k and pushing 400+ hp then it can become a problem by not dampening the vibrations enough, but overall its a safe modification on hte 420a for now until someone proves that wrong, but so far no one has had a serious problem caused by the UDP.

> our engines are pretty well balanced though so its
>not really a big deal. If we were reving to 10k and pushing
>400+ hp then it can become a problem by not dampening the
>vibrations enough, but overall its a safe modification on
>hte 420a for now until someone proves that wrong, but so far
>no one has had a serious problem caused by the UDP.

Actually it has nothing to do with balance.. It has to do with lateral harmonics that travel lengthwise through the crankshaft.

Depending on your stroke, length of the crank, thickness, support etc these vibrations can go outta control and start to ruin things.. The worst i've ever heard lately is miata owners.. a UDP will destroy their oil pump.

Ever seen that video of the bridge in washington state that twists and warps and eventually destroys itself.. same concept.. except the bridge is your crank.

ttyl

WheatKing

>to ruin things.. The worst i've ever heard lately is miata
>owners.. a UDP will destroy their oil pump.

I understand what you are saying, but again every motor is different, Miata 4g63, VW owners everybody has their little gremlins, for us is not a big deal. or we have to worry about Crankwalk because it is a problem with our turbo brothers?

I've had the UDP for many thousands of miles now, and with a turbo, and no probs what so ever. Exelant mod for 160 bucks that gives real results. Expect about 10hp out of it.

so, boost and 400 hp and udp don't mix?

I'm pretty sure this is covered in the "Thing Seen Before Forum" Buyt here goes:

Our canrs have Harmonic Dampers, other car have harmonic balancers. Replacing a harmonic balancecrt is tricky you need to worry about the balancing and rotation of the crank in relation to the new pulley. A harmonic dampr just does some work to reduce a slight vibration due to the large rotation mass of the cast iron pulley, which is heavy and not a perect balance.

Putting in AFX or Unorthodox underdrive pulley which are aluminum weight much less and don't have the damper... because they don't need it. They weighg significan;tly less than the cast iron stock pulley so the vibration isn't as great. The reduction in weight means you don't really have to worry about it. Plus, uver time, the damper ring on a stock crank pulley is rubber. Rubber breaks down and can actually create more vibration on a high mileage car. When I installed my AFX pulley the idle and everythign was smotther than it was with the stock crank pulley.

I recommend underdrive pulleys for all, NA or turbo. It's a good average of 10hp at the wheels, gop for it and be worry free.

Una salus victus.
"We are going to have peace even if we have to fight for it." - Dwight D. Eisenhower

Michael J. Kulaga
e-mail: Michael_97RS@2gntDSM.zzn.com aol IM: MJKulga
http://highlander.dsmpower.com/

All motor in the making.

Injen CAI, 55mm TB, P&P Intake Manifold, Hooker Header, GS-T Muffler, AFX UDP, S-AFC, 8.5mm Magnecor Wires, Crane Fireball HI-6DI2, SS Clutch Line, NRG Susp. Motor Mount Ins., FU/RU/RL STBs, TSW Blade 17x7.5, Bridgestone Potenza RE730, Front KVR Cross-Drilled Rotors & Carbon Fiber Pads

To Be Installed: P&P Milled Head, Rear Disc Brakes, Rear KVR Cross Drilled Rotors & Carbon Fiber Kevlar Pads, SS Brake Lines

I feel better now. I had never heard of it being bad. What he says makes sense, so WORD!!!!!!!!!!!!!