I have had one on my car now for over 12K, the car has 20K total, the car is driven very hard many track days, and it is running flawlessly. BTW my own dyno testing shows over 15WHP, this before/after test was done on mine and two other EVO's that I personally witnessed.
I have gotten reports from far more people who have run under drive pullies for well over 50K without any problems (that includes a number of DSM owners). I understand that the Hondas may be a different story (cant say about them), but for the hand full of people who claim to have problems with these pullies, not one of the tests I have seen were done under any sort of controlled testing conditions, so you have to read those reports with a grain of salt. Bearing wear can happen for a number of reasons that has nothing to do with the pulley.
If the pulley really was a major problem how is that so many people are running them with out having any problems, unless you consider more power to the wheels accross the entire RPM range a problem.

For more info see

https://www.evolutionm.net/forums/sh...threadid=38024

Actual results are kind of tuff to argue with, compared with unsubstantiated testing and hear say. In the end everyone should draw there own conclusions based on the available evidence.

Calling people names because they are doing somthing that you dissagree with, doesn't really score you any points, if you know what I mean

 

Oh, no doubt it will get you a bit more power... I had an 11 whp gain on my honda. (at the time 346 to 357) and it honestly felt like the motor was able to rev more freely. Almost a lightened flywheel effect.

Not everyone will experience problems. But if, say 1 out of every 10 people, suffer some sort of failure. It would really suck to be that one person.
And to be honest, the Evo 8 has not been out for a long enough time to confidently say a certain mod is totally safe. (though the motor has indeed been out forever)

But if you run an aftermarket crank pulley, I think a couple key things are important..

...dampened
...must retain original size (meaning if it should retain original belts)
...proven material

Just my .02

 

IMO, it's either a problem or it's not, so far I would have to say not. People will damage component's with and without the pulley, so what does that pruve?
Let's face it, all of these power adding mods will decrease the life expectancy of your motor/drivtrain. Any mod is a calculated risk, the evidence regarding the pulley so far indicates that it works well and has a very low risk.
If your worried about your car becomming seriously damaged and cannot afford to have it repaired, don't mod it, and don't race it.

Hell, people have damaged motors from using a boost controller and running to much boost for what ever reason. Does that mean any one who puts a boost controller on there car is an idiot because they might damage there motor? Maybe but those are the choices we make.

 

The engine is torsionally dampened for a reason, Mitsu would never sell a high power I4 without HTD for a reason. they need them, most people do not get crank walk, but many do. I do not consider removing an engine piece made for no other reason then the safety of the internal engine structure a wise move for a street car

 

Man you just don't get it, Mitsu also runs a certain amount of boost, fuel, timing, rev limit, etc, for a reason (engine safety). Changing those things is not a wise move for long engine life either.
The fact is I have over 12K hard miles with this pulley, and it's working fine. There are many DSM owners who have reported going well over 50K on these engines with an underdrive pulley.

Then don't mod your car, because any mod that increases power is going to increase the stress on your motor. Since the pulley does not actually cause the engine to make more power, but simply transfers power, it could be a much safer mod than say turning up the boost, etc.

 

Hi Silversurfer. I respect what you've done for this board with your extensive reviews and discoveries. Very informative posts.

But these guys aren't making the comments about the damper just to **** you off. Problems have come from this on too many DSM's to ignore. One of my friend's engine suffered some nasty bottom end failure after putting a non-damped crank pulley on his car. I have been racing and tuning 4G63's going on 4 years now and I will never put a non-damped pulley on my DSM or my Evo. Its just not worth the risk for the relatively small amount of power you get vs. the nasty engine damage it can cause.

That being said last I heard there were lightened damped pulleys in development for the 4G63. Just can't remember who was working on this.

 

i assume your talking about crankwalk. 90% of these people that experience crankwalk are using the stock oem pulley. if the crank is going to walk.. well its going to walk. aftermarket pulley or not. the same could also be said about the 2600 clutch by act which i had in my car for over 88,000 mile with no signs of crankwalk.

 

No, I'm not talking about crankwalk. I'm well aware the crank pulley has little to nothing to do with crankwalk. My friend had a 6-bolt 1G, so it definitely wasn't crankwalk.

 

I have had a crank pulley on my 300zx for 4 years no problems at all and one on my talon for about 2 years still no problems.
i will be putting one on my evo also, it spools up the turbo alot better and revs easier.

 

funny that this should come up now, we were just talking about unorthodox in another thread.

for my part, i've seen enough evidence first hand to hold a pretty strong opinion: people on different platforms having problems with UR crank pulleys, the company's response to those problems, and warnings from tuners i respect who predicted those failures with flawless precision.

to me, UR seems like a company that doesn't do any valid R&D, doesn't have any real understanding of what it is they are doing, and doesn't know what it takes to make a quality product, understand its benefits and limitations, and stand behind it.

am i ready to claim that using a crank pulley will destroy your engine? no. and some people are going to have good luck and be happy with them, and some cars are more likely not to have problems than others. i would not claim to have all tha answers, but i am willing to say i don't trust UR to know any more than i do about it, just like they clearly don't know how to build a hard pipe kit, and don't care:

https://www.evolutionm.net/forums/sh...ight=hard+pipe

"...I just don't get the price or design of that plumbing kit. Please don't take this as a personal attack. I just think Unorthodox has is ripping you off."

-david buschur


the moment Buschur or RRE or someone else i trust comes out with something similar and thinks it's an effective mod, i'd consider it. to me, UR makes junk. but that's obviously nothing more than my opinion.

 

There is no evidence that a non dampened pulley will cause any engine damage in a properly running engine. Just because someone put a pulley on andf then blew up the motor doesn't prove anything. What was the extent of the damage in the blow motor that proves it was the pulley? Because the evo pulley is bolted to a hub, it has even less impact then say a pulley with the hub built in.

The factory harmonic dampner is about as dime store as you can get by the way. There is no tech in it at all it is just an elastomeric ring sandwiched in between the out and inner rings. They are cheaply and often poorly made. I have seen a number of factory ones swell and loosen up. It jus doesn't matter that much. The amount of harmonic vibration the pulley is able to absorb is nominal. Keep oil in the car and you won't see any bearing problems from a straight pulley.
One thing you won't have to worry about is seperation of the dampner and the damage it can cause, such as takign out other accesories and a hood.

As for UR pulleys, I don't see your arguement. It is simply a piece of billet aluminum. So long as it is machined to the proper tolerance there is nothing more to be done for it. UR does in fact have better machining quality then most of the other fly-by-night companies.

 

all fair enough, and as i said, i don't feel qualified to argue the specifics of our application. on the 3g eclipse, the pulley started throwing CEL's immediately, which were proven to relate directly to the design of the UR pulley. but whatever. really, i tend to defer to those whose opinions i've come to trust over the years.

mike from RRE said a couple years back that, in essence, he felt the UR underdrive pulley was a ill-concieved mod for the 3g eclipse which was better implemented in the form of a pulley kit like the AEM tru-power setup, which replaces the alternator and power steering pulleys. in his opinion, most of the gains from the crank pulley came from underdriving the accessories, rather than removing weight from the crank, with none of the risk. i'm going from memory here, but that was the gist of it. i would imagine the same logic applies to our application.

personally, that makes sense to me. that, combined with the fact that mike and EVERYONE at RRE has always been that forthcoming and logical every time i've ever asked them for advice, leads me to trust his opinion.

comes down to benefit/risk, i guess.

 

But thats a 3G Eclipse.

We ahve run the UR pullies on DSM for years now...and none have had an engine failure to date (built motors, stock motors).

The biggest downside to the stock DSM pullies of old were the way the dampener was built in - it would seperate over time or with high hp, causing the pulley to shift, timing belt skips, and bam, you wipe the head.....this has happened countless times.

 

Here is the low down on the Unorthodox or any solid pulley you are considering.

I am going to type this in bold letters and I am not even open for discussion on it.

DO NOT INSTALL A SOLD UNDERDRIVE PULLEY ON YOUR 4G63 ENGINE. THE CAR IS EQUIPPED WITH A TORSIONAL HARMONIC DAMPER FROM THE FACTORY. IT IS THERE FOR A REASON. YOU MUST RETAIN IT TO GET DAMPEN THE TORSIONAL HARMONICS THE ENGINE HAS. REMOVING THIS WILL SHORTEN BEARING LIFE AND CRANK LIFE.

You can do what you want with this information. We built an underdrive damper YEARS ago for the 4G63. It is only slightly underdriven but is SFI approved. The main reason we built this is for the reliability. The stock damper has a rubber ring it like 99% of factory built engines do. These do a great job as intended but fail over time. They fail faster as RPM's and HP increase. The damper we had built is built from billet aluminum and has a clutch style damper inside. After switching from the solid underdrive pulleys we ran WAY back to this we instantly noticed better bearing wear in our race engines.

I can't even tell you guys how many 4g63's I have built over the last 15 years. I am quite confident we are nearing the 1,000 mark. I am telling you from experience to either leave the stock damper on the car or switch to a higher quality billet unit like ours. There is NO other choice. I don't know if the unit we have for the earlier 4g63 will even fit the EVO yet, we haven't tried it. I will look into it.

For now, leave the stock piece on the car, you will be much further ahead.

David Buschur
www.buschurracing.com

 

O.K. I am stupid sometimes.

There is no way the damper we have for the early 4g63 will fit on the EVO. The stock EVO damper is aluminum and very light already. The EVO 4g63 also uses a serpentine belt, so there is no way the damper we have for the DSM's is going to work.

The stock piece is good and light and has the damper in it, leave it alone.

David Buschur
www.buschurracing.com