CaLSoNiC

After installing my UDP, I didnt notice any gains... My first impression was like WTF... this sucks.
AFter about a week, I guess my ECU went to school and learned the art of the UDP. Wow, my Max hauls *** now. Much quicker acceleration and whatnot. Im also running a good deal of power for my sub... no noticeable drop in power for that either.

Final Analysis:
GO BUY ONE!

dr_blaqueman

I bought one, havent put it on because of work and the weather, is it really worth it? I don't want 2 be dissapointed.

MaximaPolak

iTrader: (9)

Have you read the downsides of UDPs?

dr_blaqueman

I havent, can somebody give me a link?

RastaManMax

iTrader: (5)

If you're not running something that uses a whole lot of current the downsides don't apply to our car. (I sensed that somebody was going to bring up that BMW site again).

LEMAR

dr_blaqueman

I don't have subs or anything like that, will that affect me?

Ceasars Chariot

iTrader: (16)

i have had the unorthodix racing udp for a long time, i have experienced absolutely nothing negative from it. while i didnt feel any "seat of the pants" gains ..its still going to help and work on concert with other mods "the big picture"

2 Da Max

iTrader: (2)

i was thinkin of getting a motostorm one

Dave B

Last year my I was getting 14.4s@98mph with 2.2 60 foots and the UDP. This year without the UDP I'm getting 14.4s@98mph with 2.2 60 foots. I removed the UDP because I didn't like the way it made my car drive and it introduced a little more grainy vibration at all rpms. That's my take.


Dave

MaxGR97

Ive been thinking about getting the motorstorm UDP, becuase its basically same thing, less money, and lighter too! But i dont know if its worth it, cuz some say they felt improvement adn ppl like dave b even SHOWED in 1/4 mile it didnt do anything. So im deciding if its worth it....

RideTheMax

I like my moto

Kolyan

does anyone else have comments on UDP? I wanna get this mod, i am just worried that it's a waste of money and might cause problems (even minor). I do know the amp loss, but since i don't have a system i think i should be ok here.

I30tMikeD

iTrader: (8)

First, thanks for searching!

I don't know what mods you have now, but a UDP would be at the bottom of my list. minimal gains, maybe .05-.1 1/4 mile gain.

Kolyan

search hasn't been working for some time now

Kolyan

i did the search on google and found only negatives about UDP, here and on few other maxima sites people have only positive sayings. so i'm just confused.

ny96max

i have the RVM on my max and it took a lil more than a week as well for my car to get a lil extra kick from it.

enjoy!

Ant

Dave B

I've studied numerous time slips and I can't even see a gain of 0.03 when I had the UDP installed.


The factory crank pulley IS a crank dampener. There is a rubber band sandwiched inside the pulley. You'll also notice on the backside of the pulley there are ground out "pits" at various spots on the pulley. This is to balance the pulley to the crank. The first time I started my car with the UDP, I noticed more vibration and many others have reported the same thing. This isn't to say the crank will break (like some V6/I6 motors) due to more movement/vibration because the VQ has an extremely stout crank and lower block. I did some research and found out that increased crank vibrations can actually cause valvetrain problems. The problem is as the crank moves more, the valvetrain gets slightly mistimed and less power is made. The write up was in Grassroots Motorsports Magazine and the article was written by a BMW and IRL tuner. The article was quite in depth. The article also showed that adding a heavy (8-9lb) super dampener actually ADDED a lot of power because the crank vibrations became nill and the valvetrain could do it's work more effectively. These heavy dampeners are used on many IRL/NASCAR/drag motors. The article went on to test lightened flywheels. The test car was a 350hp Mustang 5.0. With a 12lb lighter flywheel, the Stang saw a .1 drop and 1mph gain in the 1/4 mile. Seeing that most Max owners go with the 6-7lb lighter Findanza flywheel, I'd estimate they're dropping maybe 0.03-0.05 in the 1/4 mile. Lightened flywheels do not affect the crank, but unbalanced pulleys do.



Dave

matty

iTrader: (54)

Very interesting...Mine will be coming off when my blower goes on

Dave, I actaully do notice the same vib that you tallking of...I have a fidanza as well

-matt

MrEous

iTrader: (11)

This was the reason I opted not to get one...

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

Brudaddy

iTrader: (2)

This is all very interesting. I never really knew how the UDP really worked. I have seen a lot of people getting it, but I am glad I read up on it some.

It is really hot here, and I know that the air conditioner compressor is hard enough on the alternator at stock amps, let alone at a lower ampage. I don't know if I want to do this or not, esp. if Dave B says that it didn't help him at all in the 1/4 mile.

Dreizehn

iTrader: (4)

The flywheel is directly connected to the crank, how would it not affect it?

You saying that the vibration is dampened with the pulley hence no affect from the lighter flywheel?

Just trying to understand your point of view...

vsamoylov

u guys are tripping. udp will give you performance. it lets ur engine rev up faster because it is lighter and there is less mass to rotate. ur are supposed to use a torque wrench also when tightening it.

Dreizehn

iTrader: (4)

Really? I hand tightened mine...

vsamoylov

lol that a good one. no i meant that some poeple just use a braker bar and tightned it with all their strenght

Dave B

It's my understanding that the flywheel's mass and diameter serves as a dampener in that there is more rotational area to dissipate the vibrations. The crank pulley dampening material helps the pulley act like a larger and heavier unit.


Removing 3 lbs from a pulley that is only 6" in diameter and situated directly on the crank isn't going to make a huge difference at all. Rotating small diameter objects directly off the crank doesn't have near the rotational inertia as a set 17" wheels does. I wish I had researched UDP before getting mine. This car has been a huge learning experience and at least I've learned not to make the same mistakes twice

As for torque, you need ~90 ft/lbs and then an additional 1/8th turn I believe. This results in a torque value of close to 140-150ft/lbs.


Dave

vsamoylov

yeah but still there is less mass to rotate. and 3 pounds off a small 6" pulley is a nice amount.

matty

iTrader: (54)

Im with Dave....I have been getting a vibration threw my car ever since that thing was put on...I feel it mostly at low RPM's, say about 2500 in 4th or 5th...Im having it taken off on Wed and Ill sell it with the belts
-matt

sbslacker

iTrader: (1)

Dave....question...

What about the UR Street Charger Crank Pulley? Stock diameter, yet still lighter than stock. Would this be a better option than the smaller UR UDP? Would this help dissapate engine vibrations and in turn help the engine/drivetrain perform better?

Dave B

The problem with the aftermarket pullies for the Maxima is that they don't have the dampening material. That's the key.


Dave

kenji

iTrader: (1)

Hmm. at 89k my serp belts are getting a little old and I was going to replace them. I was considering the addition of a UDP at the same time, because I would need new belts anyways. This sort of 'puts the icing on the cake' for UDP's IMO.. I would rather stay with stock pulley for a couple of reasons now:

1. Aftermarket parts are notoriously bad, in comparison to OEM parts, especially those that are directly connected to the drivetrain.
2. With A/C, P/S, and a High current amp capable of 1200watts, a UDP would result in too much additional strain on the alternator.

So what's the best place to by stocksize belts, (if I am replacing all of them) and who's got the best write up on replacing them?

Input is appreciated!

-Kevin

Kolyan

well...this post saved me some money..thanks

vsamoylov

i am telling you. it is not because of the udp. it might give off some vibrations but not that huge.

Phatmax98

iTrader: (2)

well...I don't know who to believe on this topic...seems to be everyone's personal opinion...so I will give mine...I have had mine installed for about 8,000 miles with absolutely no problems, no valvetrain problems, engine problems...nothing! I did not notice much of a gain, but it was there...IMHO it's not worth $190 from unorthodox...if it was cheaper it would be a better deal

Dave B

Elaborate on how you know this?


Dave

vsamoylov

well think about it. a udp works as a damper but not that big of a damper.a reason u could feel vibrations in your car is ur engine mounts coulbe be bad and when driving if you feel a vibration, you tires could not be properly balanced. thats is my 2 cents.

I30tMikeD

iTrader: (8)

Even [B]if[B/] a lightend/smaller diameter UDP proved to cause no ill side effects the power gains from it are not worth it. There are many more performance mods to spend money than a UDP.

vsamoylov

yeah that is true but all mods count in some way or another and contribute to other mods

Brudaddy

iTrader: (2)

and all roads lead to Rome, right?