i was looking at the group deal for the Motostorm pulley and i know that they have some downside to them such as reducing your engine's life. so that got me wondering. what are the pros & cons of having the udp pulley?

 

Pros, free up HP. Cons, "decrease" power from alternator, cause vibration.

 

They cause vibration according to what?





http://www.greghome.com/Greg's%20Gar...e%20Pulley.htm

 

dude i have the unorthodox pulley and i think its great. I had it installed for about a month and no problems here. Granted i havent had it that long but for the time being its great. Get it and if you dont like it, put the stock one back.

 

Supposedly the pulley acts as a harmonic balancer, from what I read. And because it's lighter the vibrations are more noticeable, more in 5spds I think.

 

Read the following site before buying...

http://www.motorvate.ca/mvp.php/521

 

Nope, VQs are internally balanced. Plus why would it be any different on 5spds?

 

yes. the vq is internally balanced and i have had mine on for a whie and have seen no noticible difference in vibration or noise or anything. i bought it sice i heard it is helpful in the lower rpms and since i have a injen style cai ( which decreases low end response) i thought the pulley would counter act the injen low end loss. i think i was right but cant be 100% sure with out a dyno. but the car feels alot better with it. just my .02

 

Any AC/alternator problems with it yet?

 

Believe what you want, but the OEM pulley also serves as a dampener. There is an elastomer ring on the OEM pulley and it quells crank vibrations. Will the UDP causes engine damage? Probably not, but increased crank vibrations can cause poor valvetrain operation and possibly reduced poor.

I had a UDP and noticed increased vibration at all rpms. After looking at my timeslips, the UDP made no difference in the 1/4 mile. All it did for me was increase engine vibration (nothing terrible), made launching harder due to less inertia, and made for unsmooth shifting (again less inertia).

Is the UDP still on my car? No and I'm much happier. Save your money for something else.

 

Lot of mixed reviews on the UDP's...

 

OK so now is there a way that u can change thge UDP and still have ur system pumpin? I have a 1,500 what amp, 4 10" sub's and surround sound inside.. If I change the amp's on my alternator (200 amp alt) will this correct the loss of power at idle or will it be the same ? ??

 

OK so now is there a way that u can change the UDP and still have ur system pumpin? I have a 1,500 what amp, 4 10" sub's and surround sound inside.. If I change the amp's on my alternator (200 amp alt) will this correct the loss of power at idle or will it be the same ? ??

 

You can get a lightened pulley that is the stock diameter so there is no loss in alternator output.

 

i have the unorthodox racing udp and didnt notice anything at all different with the car, i agree with dave regarding performance, i wouldnt expect much ! but i thought it was a cool mod to do !

 

Ill an UDP cause problems to engines with 150k miles on them?

 

no problems here, and i have a sound system, ps2, and tv hooked up. i check my battery level every other week or so and every thing is normal

 

i've raced 2 maxiams with same setups and mods that i've got, EXCEPT the UDP. both maximas pulled harder in each gear. we all had full exhuast y-pipe back, intake, etc. one even had 19" wheels, which probally slow him down a bit. they both pulled on me. maybe it matters if you have otehr mods done. i dunno what you guys have done to your cars? didnt they have dyno sheets to show HP gain?

-rafal

 

i believe i wasted money on my pulley no difference in the car really

 

wouldn't vibration causes more engine wear? i hear it causes it to lose 40% of your engine's life and that's a lot. i expect to have my max for at least a couple of years to come.

 

this is good. this is why i posted about it. i'm not so sure if i should get it and end up wasting money or end up hurting my car in the long run.

 

dude, with a kicking sound system, you can still kick it all the way up with some capacitors, this will knock out some energy consumption. i have a clarion setup with a 1000 watt 4 channel amp and a 800 watt mono amp, and a kicker L7 12". all these are supplied by 1 farad and a 1/2 farad capacitors. before i installed these caps, headlight would dim each time my kicker hits its peak. after the caps. i don't see any energy drags at all...

 

So anyone know for fact the effect on engine? Does it really put extra wear on it?

 

Well I have about 50 timeslips with the UDP and 30 timeslips after removing the UDP and there's no decernible difference to be seen in ET or MPH. Assuming the same weather conditions, some days I was quicker with the UDP, somedays I was quicker without it, and sometimes the performance was the same. That tells me it did nothing.

Save your money for something else.

 

i got one and i dont think its worth it...i didnt feel any real gains off it. jus saw it rev quiker then b4. i got 2 15's pushed by a 2000 watt amp(thats only whats sitting in the trunk )...i havent noticed any diff in my radio or overall loudness of the mid's n hi's...id say u spend ur money on a better part

 

An UDP will help more for Turbo vehicles and a lightened one for SC ones. F=MA the more force the more mass is going to affect it, especially with a rotating part such as this. If you are NA and esp if you have a big stereo then it may not be worth it.

 

It will rev quicker and give you some gains but until you get a lot of other stuff, either just about every other bolt on or FI then it may not be the next mod on the list.

 

Hmmm interesting

 

well as of now i have an intake and y-pipe. i just figured the UDP would be one of those cheaper mods i can do to improve performance. i dont plan on getting a monster sub thats heavy and takes up trunk space but do plan on just upgrading my speakers all around so that shouldn't affect the alternator that much.

 

I have an UDP and it helped keep my times stable. Mind you I'm at 4000 feet elevation and I'm still learning how to launch. Before I had my MEVI I raced and was consistantly getting low 15.7's. My friend has the exact same setup Intake, Y-pipe, cat-back, minus the UDP, and same weight reduction and he is anywhere from 15.7 to 16.0. We'll even switch cars on a few runs and I can't keep his consistent for anything. Maybe it has to do with the car or maybe it doesn't. But this is my experience with UDP. I like mine, but each have their own opinion. For Dave B it didn't work. I've had mine for a year and a half and have had no problems whatsoever. I personally think it's worth it. But your experience might be different and it might be a waste of your money.

 

In my opinion I don't think a UDP is kind on the engine.
Consider it like a smaller cog on a bicycle. You prefer having the bike at a smaller cog during take off but as you pick up speed if you stay on the same small cog you get tired. So you switch gears to keep up with speed.
Now replace yourself for an engine in your car. With the smaller UDP, engine spins faster hence faster take offs but at high speeds that engine still stays on the small pulley leading to high revs, more internal heating, more wear.

 

hmmmm never thought of it like that.

in addition to variable intake and variable valves, we might look into some type of variable pulley system. lol

i thought that the pully really only affects the altenator and once it gets going theres really no difference. i thought the pulley and the belts really dont do anything as far as the engine, its just an external pulley that just runs the belt for the altenator and accesories. i think the complete rotation of the stock pulley would take longer since the diameter is larger than the smaller pulley and the samller pulley would rotate faster due to reduced weight and smaller diameter but i cant see how it would tire out the engine. i can only see it tireing out the altenator. let me know if i am completely wrong.

 

not completely wrong at all.
I was basing it on the fact that our engines are already alittle free revving with stock pulleys. 2200rpms at 60mph. Other cars are at 1800rpms at 60mph. So with the smaller pulley that frees up the engine even more.
I may be wrong too.
But the alternator tiring out is not likely.

 

Well if the engine pulley was actually driving the gearing via a belt/cog then yeah, but that's what the transmission is for. The crank pulley is just driving the accessories. A UDP may let the engine rev quicker due to the lite weight and smaller diameter but the tranny is taking care of your gearing. The engine is going to stay at the same RPM regardless of pulley size/weight, it will just reach it quicker. I would think a UDP is actually better for your engine since the crank doesn't have to work that much harder to spin the "heavy" pulley.


But what do I know, I'm not a mechanical engineer. I'll tell you how I feel about it after I install one this weekend.

 

That makes no sense as your example is referring to gearing and rpm. The udp doesn't affect either.

 

im begining to think that no matter what, there will be some mixed reviews. i saw the lil sheet on motorvate.ca (i think thats the site) and saw the lil write up on how it affects altenator performance and as far as i can see is the only problem. i dont tink the pulley will dammage the engine, tire it out, wear any parts, cause ballancing issues, or any other serious problems that will cause premature engine death. i also dont believe the pulley will cause any amazing increase in performance. i bought one cause it was cheap, easy to install and just wanted to have one just to be sure i squeeze as much power as possible before getting more expensive performance parts like a MEVI $400+, ECU upgrade $370+, VB Mod.......... I paid 80 bux plus 25 for belts for my DMS UDP. y pipe 160, injen knock off 65 bux. these are all all basic bolt-ons and IMO are the 1st things that should be installed as far as performance, consider this stage 1, then move on to something more extensive like the ECU, MEVI, Tranny parts.... then move to stage 3 which will be like turbo, SC, nitrous.....

if u want to get the UDP i wouldnt stop u cause i bet that with the addition to everything else it just might help. but if u decide to save your money and get something else i support that decision also. hope this helps man :-)

 

The ECU is LIGHTYEARS ahead of the UDP in terms of actual power gains. I'd have to say the ECU adds nearly as much power as the y-pipe. Intake, ECU, and Y-pipe should be the first power mods for any 95-97 Maxima.

 

Just wanted to add my vote in. I agree with Dave B on this issue - I have a Motostorm UDP installed, and while the car does seem to rev faster/freer, it is by no means faster! I would, however, buy it again, consider some have found it to be a good tool. And for $100 you can have one installed on your car DIY. Sometimes it's worth it to take the chance.
-Cyrus

 

i agree ECU is way better as far aas perfrormance but it is more expensive than a tipical bolt on.technosquare did the GD for 370 and if i remember correctly said they would never do it that cheap again. now im not sure what the normal price is for TS but if i remember correctly the JWT ECU was like 500 bux or so. what i meant as stage 1 and 2 and so on is performance parts as far as price. ECU is a great power mod but a lil too much for someone just getting into the tuning of the maxima. id say start off with cheap mods like intake, Y-pipe, UDP, Cat back maybe.

 

No disrespect, but some of you guys are saying that you can tell it revs faster but you cant tell any power gains? If rpms increase faster then your mph go up faster = the car is faster, Right?

I want to get one really bad but I keep hearing that they don't give any gains

BUTTTTT

They provide more of a gain to autos Right?