I was thinking about it as a possible next upgrade, and I'm just curious...anyone here on the org have an UDP on their Max and care to tell me what's good and what's bad? I've read up a bit, and it sounds like people have no issues with accessories after the install, but I feel I'd still need to be wary as far as my water pump, draw on the alty from HIDs and system, etc.

What's the thought on UDPs here? Would I be better off just swapping my stock pulley for a LWP?

Sorry if this is a repost. I'm late and it's tired.

 

+1 Im curious about this too.
I want to get more power out of my engine but I cant sacrifice aux power. I am planning on getting a touchscreen/multiple subs etc etc.

The guys who do my stereo work told me not to get the UDP because they need the power for the system... but I dont think they really know for sure.

Also, maybe if you hook up an extra battery it can compensate for the power loss in aux systems?? what u think?

 

Ive had mine with out problems so far(4th gen 5speed). I have a UR pulley that I bought on her new for cheap. I really wouldnt run cheap pulleys. I cant say that I would spend $200 either though.

 

Here are some thoughts regarding the pulley.

- You will notice that the motor tends to spin a little more freely, and acceleration feels faster.
- An UDP alone has had different opinions varying from yes it feels good to no it doesn't have any effects.
- A good brand pulley is definitely the way to go if you get one. Cheaper pulleys tend to make noise and also eat up belts for some.
- An UDP does not create HP it only frees up HP, so do not expect tremendous gains.
- An UDP works better with most all bolt-on mods and it is a catalyst to everything else.
- An UDP is not really recommended if you have a system in your car or multiple electronics as it will deplete the life of your alternator faster.
- An UDP seems to be fine without any additional accessories or systems in the car as far as my experience has been.
- I did notice that my revs climbed ever so slightly faster.
- Again a combination of other mods will see more benefits from the UDP vs just the UDP alone.
- A few members have had the UDP along with their systems and not noticed any detrimental effects from it. That might be from having a healthy car or the effects haven't hit yet.
- I liked my UDP and have not had any issues with it. I am currently selling it since I have a big system and other electronics and would rather sacrifice not having one then I would this equipment.

So in summary, would I put it back on? Yes, if I didn't have my system and other electrical accessories. Would I pick a quality pulley? Absolutely! Which brings me to my plug-in for this post. If anyone is looking for one with all the new belts required, I have one up for sale. It's an Unorthodox Racing Underdrive Pulley. Probably the best one out there for our cars. Link to thread is below, and hopes this helps.

http://forums.maxima.org/5th-generat...5-drivers.html

 

Pros- installed the wrong way = damaged motor

Cons-costs money

 

'

How is that a pro??? Damaged motor doesnt really sound like a good thing...

Everything costs money thanks for the pointing out the obvious... Can you tell me a mod I can order for my car that they give out for free?

 

My STS Mod is free for 6-speeds. Ok ok, not free but only cost you a little time and the price of 1 bolt.

 

Thanks for the heads up. I've already got a few bolt-ons, so hopefully if I do go with the UDP it'll give my car little better feel acceleration-wise.

As far as worrying about losing power in the alt., my question is this: Would it be beneficial to install a higher-powered alternator to make up for the lower rotational speed? I know that would probably cost more than it's worth, but if it'll do the trick, then hey, why not. Besides, I know alternators tend to be a common issue on the Max...

Either way, if I'm only pushing a 1,000 watt system, I don't know if should be that very concerned. It's not an over-kill system...and it's not turned up all the way.

 

That's what I did was purchase a higher output alternator. The amps on a stock alternator is about 110-115 I believe, I picked one up that was rated at 125amps, and also up to 149amps at 6k+ rpms. So I'm covered. It won't hurt that's for sure. For the best deal in the world on an alternator call up Lamar's. Just got one from them last week and installed it. They usually do reman alternators, but they do a good job and it comes with a warranty. It's local to me, but I'm sure they'll ship if you ask them.

http://www.lamarsalternators.com/

 

Our water pumps are timing chain driven, so no issue there

 

How does one install a pulley the wrong way? You mean install it backwards? Not talking nicely to the pulley when installing it?

S

 

I don't have an under drive pulley on my maxima and would not consider it because i had one on a previous car and it came off shortly after i realized my A/C was not as cold, the HO alternator could not sustain a JL1000/1 with volume at 3/4, steering was just a touch harder to turn and whined all of the time when i turned the wheels while not moving. The only pro to me was that the motor did rev up a lil faster but it wasn't worth it at the loss of power to my accessories.

When i took the under drive pulley off i installed a light weight stock diameter pulley and still retained full power to my accessories plus the car reved faster than with the stock pulley but just a hair slower then the under drive pulley. I got the pulley's from stillen, I'm pretty sure they make both for the maxima. They are way lighter than the stock pulley.

 

Cool, dude. Thanks for the info. I kinda figured that'd work in the end...I'll check out the website when I'm not stuck at work.

That's good to know. Every tech I've talked to has told me how worried I should be about my water pump. As long as it's on the timing chain, maybe I can get them to stfu now.

I had a friend install a UDP on his Prelude and not torque it down enough. Needless to say, at about 6,000 RPM we heard a BANG, and that was the end of it.

I guess that could/would suffice as "the wrong way?"

 

Most of the gains come from the rotational weight loss, not the underdriving.

Get a stock sized lightweight pulley, and forget about worrying about alternator output.

 

[quote=nzelinsky;7164040
Also, maybe if you hook up an extra battery it can compensate for the power loss in aux systems?? what u think?[/quote]

Maybe.
But why a power enhancer if it forces you to add more weight?

 

no offence here but who ever told you that HID's draw more power they lied to you they actuality draw less power than your stock bulbs do. they do require about 2x the power for about the first 5-6 sec when you turn them on but after that they draw a lot less.

 

I know. That's what I'm worried about is the initial powering on. Not when they're actually running.

One of my fog lamps (it's ballast is ruined now unfortunately...) used to refuse to ignite unless the car had been running for a minute or two and charged the alternator.

 

The comments from Deckdout2 are spot on. (Nice job, Decker!)

Here's another consideration:

If the "underdrive" aspect of the crank pulley replacement bothers you, get the factory-diameter pulley. You'll get all the benefits of the lighter device, but none of the potential electronic problems. And when it comes to replacing belts, you can go OEM without the angst of which belts to fit.

It's the reduced pulley weight during spin-up that makes all the difference when reclaiming power wasted as inertia, not so much the reduced power draw on your accessories.

Research Unorthodox Racing Crank Pulley. They make a high quality replacement part.

And last, as with every other incremental mod, you'll feel it for a day or two, and then it just becomes the new normal. The gains are real, and you will feel it, just keep your expectations in check, is all.

 

i think im gonna get one now thanks

 

He's basically saying that there are no real pros; and he's right. Although you'd have to be particularly hamfisted to fubar an UDP install.

 

has anyone dyno'd before/after with UR's pulleys? The stock diameter pulley listed on their website estimates a 6-10 HP increase. Can anyone verify this? I know everyone's been saying it helps the motor spin up faster and frees up power, but I was just curious as to whether or not it's been proven other than what UR is saying

 

I've had a UR UDP on my car for a number of years and kind of regret installing it. I didn't notice any performance gains, and my lights dim at idle with my (average sized) system running. If I could do it over I would just stick with the lightened stock sized pulley and call it a day.

 

6-10 HP is a downright lie.


The motor will rev up faster in neutral since it's only spinning the crank pulley, flywheel/clutch or driveplate/torque converter. Once the car is in gear though, it's spinning those things plus the axles, rotors, and especially the wheels. Think about all the extra rotational inertia those other items possess combined, then think about how little is removed switching from an already small and relatively lightweight stock pulley. Ummm yea...fraction of 1 HP.


And yes I know flywheels work on the same principle, but the inertia of a rotating body is directly proportional to it's diameter. Flywheels are wide and that's why lightening them has a big effect. Not so much with a crank pulley since it's so small to begin with.


If you want to go with the "but the accessories are being underdriven" angle, that's only true of the alternator. The water pump is chain driven, the a/c compressor doesn't count since the a/c is disengaged past a certain RPM and/or @ WOT, and the power steering pulley isn't underdriven in the first place. So the alternator spins slower, big whoop...fraction of 1 HP.

 

Yeah that's kinda what I figured..I don't see how a lighter pulley is going to free up 6-10hp by itself. That's in the ballpark of putting the nwp spacers in which actually have been tested and proven. They show before and after dyno charts on UR's website, but who knows how accurate it really is. Then again I've never tried their pulley so I can't really knock on it.

 

Wow, that's pretty strong. Perhaps you should report UR to the BBB?

Sarcasm aside, I noticed their price has gone up from $200 to $250 in the last few months. That extra $50 would have given me serious pause earlier in the year. Not sure $250 is worth the gains (however real or make-believe.)

 

Well, searching is always a useful past time...

http://www.greghome.com/Greg's%20Garage/2002MaxSE/2K2UDP.htm



9 BHP for ~$250.

What does a cat back give you? About zero for twice that?

 

I dare you to find another back-to-back comparo with similar results.

 

Yes there is one " Advanced timing "

 

lol.
Why don't you disprove this one first....

 

I don't really feel the need to. I've been around maxima modding long enough to know what works and what doesn't but hey, it's your money!

 

From what I've researched in the forum regarding advancing the timing, it works best for the 5th gen, not the 5.5 gen like the OP is driving.


Fair enough.

The crank pulley doesn't offer the highest return on the investment -- I don't think anyone would disagree with that assessment. There are better things to pursue.

 

Please don't misunderstand, I completely understand if you don't want to discuss why he got gains and you didn't.

Sorry your dyno results didn't live up to your expectations.
What numbers did you get, anyways?
Did you show a loss, or just not enough gain for the $?

 

Just go for it dude. Go for it.