People with aftermarket UDP's......
 

Since the search isn't working, I thought I'd try and get some responses from actual owners of aftermarket udp's.

1. year of maxima/mileage
2. brand of udp
3. miles driven with udp
4. problems with udp(if no problems, type n/a)
5. gains(or losses) with udp

I think this would really help me and others decide whether or not to get an udp.
-Paul

I keep hearing UDP what's that?
Never mind i found the answer. FAQ baby! :D

under drive pulley :thumbsup:

1. '97/128k
2. Unorthodox
3. 30k
4. n/a
5. Didn't really notice that much of a gain. I just noticed that it revs faster.

1. 99
2. Definitive Racing
3. ~15,000
4. n/a
5. Decent gains for the price. Better throttle response. Worth the money if thats the bottom line.

Hell, I wish we could switch out ALL our pullies. I did an Unorthodox Racing complete swap (4 pulleys) on my wife's Eclipse GST and WOW!!! MUCH different!!

i can't wait to install... i have mine all ready.

1. '96 w/ 115,000
2. Unorthodox Racing
3. approx. 11,000 (put on around 104k)
4. n/a
5. Noticed slight improvement. About the same as the difference between a/c on or off.

I had most of the other bolt-ons so I decided to get one. Throttle response seems a bit better. Seems to rev more freely.

anyone make a reconmendation between unorthodox, definitive or other brands?

i got the definitive.. not installed it. It comes in nices finishes and has a bronze seal or something like that. Plus i think its less expensive than Unorthodox. There was a group deal on definitive.. still is...

any performance difference whatsoever?

1. 1995 Maxima SE 5-spd (93,000 miles)
2. Unorthodox Racing UDP
3. Driven about 4000 miles so far with UDP
4. N/A
5. Not entirely the UDP, but I did gain about 7HP on the dyno after I changed my plugs and UDP (I would attribute about half and half to each change)

I would recommend this mod as, "one of those mods to take you farther down the road". It will only help for performance, even if it is just a bit.

I put on my UR UDP and my Y-pipe and B-pipe at the same time, But when I nail it I tach up much quicker. The only recommendation I have other than do it, is make sure you get good belts. I couldn't get the right size belts without going to the cheap brand, and they are real noisy. I am going to change them soon. I have an auto and when I launch from 2500 RPM, I get to the top of the power band much quicker. It is way faster out of the hole. Oh, and I have 105K Miles, and have had no problems, especially with spankin Honda's, for the last 7000 miles. I know a lot of people talk about loosing voltage...BLAH BLAH BLAH, it is a myth. I have a kick A$$ stereo, alarm, radar detector, phone charger, etc, etc, and no voltage loss. The pulley only looses 15% of circumference, it is about 4 1/2 lbs. lighter than the stock pulley. You will enjoy the difference. Every little bit helps.

Oh yeah one more thing... you will notice the effects of the UDP more if you are an auto tranny. Not as noticeable with a 5-spd even though similar gains are there.

i agree. Things add up! Hopefully i will feel mine, when i put it on!

thanks for the responses guys. I think I'm gonna go with the ur udp now.

Now about the belts, which ones should I get? Is there only one or more than one belt? Can I use the belt I have now for the ur udp?
-Paul

there are two belts, just get them from ur, that way u'll know they will fit properly

1. '98/102k miles
2. Definitive Motorsports
3. about 8k
4. n/a
5. when i first put it on i noticed 1st gear felt like it wound out faster...after having it on for a couple weeks...didnt notice it anymore....thats pretty much every mod with me....


Goodyear GatorBack belts are good..

i got definitive, ready to install this weekend hopefully. So u say there is some iprovement

Get the shorter size belts as specified by UR. They would be a tad shorter. You COULD use stock belts, but I wouldn't recommend doing it half-a$$ed. You've spent the money on the pulley... the belts are a tiny bit more above that.

Why would that be?

I've personally experienced it. I would assume that it has to do with the fact that in a 5-spd, the gear ratios are shorter than in an auto so the revs are much quicker to begin with.

I've felt the revs spool up quicker in an auto than in my current 5-spd after getting the UDP.

1. 1998 SE / 72,500 miles
2. Unorthodoxracing
3. Aprrox 9,000 miles driven
4. No problems whatsoever
5. The only gain I really noticed is when I turn my A/C on, it feels like no power loss..which is always a good thing since you can race with A/C on. I haven't got a dyno so I don't know exactly how much HP I got..I feel the mod is worth the price though. Also, I picked my belts up from an Auto Zone for a fairly good price. I also installed this myself. If you want, you can order a new crank seal...not sure if this is recommended or not, but I played it safe. That was about $8 shipped from a Nissan Dealership. Hope this helps.

how much do the OEM belts cost and are they difficult to change?

~$15 and not really. Get a FSM / Haynes / Chiltons. It really helps.

how much time we talking?

The belts are not easy to change, if you get the new shorter belts, which you should. They fit VERY snug and you have to put quite a bit of elbow grease into slapping it on, to get it over the outer lip of the pulley, onto the grooves. But it is do-able.

I've had my UR UDP for about 2 years and 30K miles. No problems. I dropped ~.1 and gained 1mph in 1/4 mile on average.


Dave

thanks dave, that clears some stuff up :thumbsup:

1. 98 Se, 5spd
2. Definitive
3. 80 miles
4. no problems yet...
5. Just installed my pulley. Gains are moderate. Car revs faster and seems to have a better kick, with or without the A/C. Good mod for the price!

anyone have a part number for the seal?

UDP rev the engine faster in every gear?
Does this change the gas consumption alot for anyone?

if anyone needs the part number for the front crank seal its 13510-31u00

I should correct this now. I went through my slips a few months ago, increment by increment, I think I might have gained 0.03-0.04 and .5mph with the UDP, if that. I had orginially said ~.1 and 1mph, but after close analysis, it's less. I apologize. On the dyno I figured I gained about 2-3fwhp according to my plots. I removed my UDP a few months back because of some information I read about UDPs causing crank vibrations which can affect the valvetrain and possibly make the car loose power and increase engine vibrations. I did notice that the day I installed my UDP, there was more engine vibration. This is because the stock pulley has a dampener material and the UDP does not. After reinstalling the stock pulley, the VQ was smooth again. I've also been to the track and it appears I'm no slower/quicker without the UDP. This year I've run 14.4s@98mph with 2.2/2.3 60 foots and last year with the UDP I ran 14.4s@98mph with 2.2/2.3 60 foots.


Dave

1. 99 GLE
2. Unorthodox
3. 15,000 miles
4. n/a
5. Gains are minimal. Car revs faster (especailly with a y-pipe), the A/C performance is no big deal. I auto-x mine so for me it was noticable improvment.

Dave, where and what exactly is this 'dampening' material' on the stock pulley that you're talking about? Is all the stuff I'm hearing about the VQ being internally balanced not true? I didn't notice any additional engine vibrations after I had the UR UDP installed. Did you notice a difference just sitting in the car with the engine running at idle or are you talking about during acceleration?

http://images.cardomain.com/member_i...210980_100.jpg

The material is 1/8" thick ring of stiff rubber sandwiched just below the lip of the accessory pulley (the large one). It's hard to see this material because it's so thin, stiff, and is black like the pulley. Take a flathead screw driver and you'll be able to feel the difference between the rubber and metal.

The VQ is balanced, but when you put a flywheel on one end and a small pulley on the other and spin the motor up, the crank will become slightly unbalanced. That's why the pulley has dampening material. On the back side of the pulley you'll find 2 to 3 round indentions. Those are for balancing the crank in relation to the pulley. The UDP has neither of these.

I noticed more vibrations the second I started the car with the UDP. I also felt the vibrations at all rpms. Above 5000rpms, the engine almost sounded a little strained. Don't get me wrong, the engine was still much smoother than most other engines on the market, but I did notice the VQ didn't purr like it did prior to the UDP.

Just my opinions.


Dave

so do you think the udp is not worth it? or is that just what you're experience leads you to believe? i dont know if i want to go through with it if it might cause vibrations

Did you change out the seal Dave?

After owning one, I don't think it's worth it, but a lot of others will disagree which is understandable. The vibrations I noted have been observed by atleast three other 4th gen owners. I've never heard of a 3.5 VQ owner complaining, but the two 3.5 VQs I've driven aren't near as smooth running as the 3.0 VQ, so that might be why they aren't complaining.


Yes, for $5 it's worth not having to worry about an oil leak after reinstalling everything. When I removed my UDP, I had to use a gear puller to get the SOB off. The tolerance was simply too tight. The stock pulley slides on on off, but not the UDP after it's been heated.


Dave

im gettin mine soon, cant wait