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Underdrive Pully

So it claims to give 10ish hp for a fairly cheep price, yet I have never heard of it before. Any info on this? Does anyone have it? If so give us the scoop. Or did I just miss a thread that came and left?
 

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been around for almost 2 years now actually. there are 2 members on here with the UR pulley, one for well over a year now without issues. as far as gains, i dont' think i saw a dyno from either to show anything?

very touchy subject on here as the stock pulley has a function other than just rotating that the UR pulley will never do. so any miss on the install and you can be screwed, and MIGHT lead to issues down the line from balance issues.
 

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There is a reason why Ford developed the Dual Mass Dampner (our factory crank pulley/harmonic balancer), because on the Duratec, your standard harmonic balancer wasn't enough to keep the vibrations away from the crankshaft, which causes crank whip/walk which ultimately causes spun main bearings, a la dead engine.

Over 10 years now of Duratec V6 modding and there is no MIGHT or MAYBE which underdriven crank pulleys, it WILL cause your engine to fail. The question is, when?

Read up on Contour.org forums, the DMD (Dual Mass Dampner) is a required modification.
 

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Let's say you had your crank balanced to less then 0.1 of a gram, which is a service being offered by a local engine shop. Do you think that there would still be an issue with crank whip/walk? I am not considering changing my pulley but I am curious.
 

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Let's say you had your crank balanced to less then 0.1 of a gram, which is a service being offered by a local engine shop. Do you think that there would still be an issue with crank whip/walk? I am not considering changing my pulley but I am curious.
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Ford has already done that, Ford added larger counterweights on the 3.0's crank versus the 2.5's crank and you see the DMD was still required.
 

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BUT, there is at least 1 owner who has well over 25k on the engine without issues yet. does it mean it won't happen, not at all, but it's possible to work out ok. no one thought the 4cyl could hold boost, but now that it's been done it's a completely different story. even though the focus community gave up on boost as it was said they wouldn't take it....now everyone is jumping on it.

until a few 6's actually go through it and show the issues, we won't know for sure on the 6. that's all i'm trying to say
 

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BUT, there is at least 1 owner who has well over 25k on the engine without issues yet. does it mean it won't happen, not at all, but it's possible to work out ok. no one thought the 4cyl could hold boost, but now that it's been done it's a completely different story. even though the focus community gave up on boost as it was said they wouldn't take it....now everyone is jumping on it.

until a few 6's actually go through it and show the issues, we won't know for sure on the 6. that's all i'm trying to say
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Same block and crank in every 3.0. There are 3.0-swap 'Tour owners with more mileage than that with UD pulleys and no crank walk/whip, but it happens eventually, the mileage varies everytime. It's like playing Russian Roullette, never know which pull of the trigger will contain the bullet in the chamber.

The Focus community didn't get the Duratec until recently, they had the Zetec prior.
 

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i am going to try the under drive pulley along with the new motor mount from rpm and 8 pound fly wheel and the clutch master stage 3. Maybe the msds headers but not sure , maybe the cpe headers?
 

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go into more detail no one has done this with a six before so how can you say all this. Just on assumtion? but please tell why you think it will drive like shit!!!
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Because its the same engine Contour owners have been swapping in their cars. They have already documented noticable vehicle vibrations with an underdrive crank pulley, the MTX-75 (Contour) and AGM-5R (I think that is the designation) uses the same size clutch and flywheel combo and plenty of Tour owners have changed to lightweight flywheels and high-torque clutch sets over the past decade. Driveability is not much of a concern for most of those who do the 3.0 engine swap.
 

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so what you are saying is that yes there will be vibration but also it will be drivable . Just getting used to it is the main thing? And if i am not concerned with a little vibration ill be fine ?
 

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dude, frickin read the whole thread.

it causes crank whip/walk and spins bearings. that = death to your car. not roughness.




thats only talking about the underdrive pulley.


with regard to drivability, putting a 8 lb flywheel, and then a stage 3 (kevlar, i believe) clutch in the car, it would be very difficult to drive anywhere near smoothly. the kevlar is very grabby, and wont transition the power without a lot of chatter. thats what i have heard about reasons why not to get the stage 3 clutch.


plus, if your not doing your turbo kit, you dont need it.
 

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well well you what , thanx for the heads up in a violent . I am still going through with it. I am not one for a nice ride thats boring to me!!!! i like difficult as is. thank you for your input. ILL let you know how it goes
 

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well well you what , thanx for the heads up in a violent . I am still going through with it. I am not one for a nice ride thats boring to me!!!! i like difficult as is. thank you for your input. ILL let you know how it goes
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While I usually applaud guinea pigs, I would encourage you to do more research on the matter especially due to the severity of the potential damage. There is plenty of material available if you do a forum search for the terms underdrive or pulley. In addition, head over to Contour.org and search for those same terms.
 

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well i did some more research and i have decided not to go with the underdrive pulley, however i am still going with the 8lb fly and the stage three clutch from clutch masters!! is was either that or the cpe headers but the waiting time is too long for me!!! i would like to have fun in my car before i go to iraq......
 

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why why why do you need to buy the stage 3 clutch? just because it says stage 3?
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Thats what Im wondering. A stage 3 clutch isnt doing ANYTHING for performance. All its doing is decreasing drivability. Unless you have the power to back it up dont get a stage 3.
 
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