I was thinking about getting and under-drive pulley for my car. does its add any extra hp or is it as useful as the electric supercharger?

 

From what most people say I wouldn't bother.
Everybody says its pointless unless you like to watch the car rev quicker...

 

Well why don't you be the guinea(alcohol + spelling = <----- ) pig and find out for us. Shouldn't be 1-3 MAYBE 4-5. It is mostly for quicker revs.

BTW Quicker revs = faster car.

 

IBseeingthreadslikethisevryday

 

The engine will rev more quickly in neutral, but once in gear it won't. No net acceleration gain, period.

 

bullsh!t. period. after my underdrive pulley and my lightened flywheel, first gear is freaking intense, second gear too, but not as much. i spin my tires all through first on most pavements. dont tell me it did jack ****


edit: btw, nismo, if you dont have this mod DONT commment on it. if you do, then ignore this part of my post. im sick of seeing people give false info on something they have no experience on.

 

Did you install the UDP and the lightened flywheel at the same time? If so, maybe the UDP did jack ****.

Everything I have read on the .org states that a UDP is beneficial for a 5th Gen (maybe 5.5 is what I read), but does next to nothing for a 4th Gen.

 

the flywheel was first, the pulley was about a week later. with just the flywheel the wheels would chirp through first and now they just break loose and spin. the pulley is around 5lbs weight reduction and the flywheel is 6. underdriving everything has most likely 0 gain. its the weight loss that helps you. also, everyone always skips out on the fact that you will notice most gains in 1st and less in 2nd. and probably not much of anything after that. so itll help your 0-60. my car does rev like a motorcycle now but i have so much more takeoff from a standstill.

 

:yawn:

http://forums.maxima.org/showpost.ph...81&postcount=7 (awaiting your response to this post in particular )

and

http://forums.maxima.org/showpost.ph...7&postcount=19


BTW, the reason i never got it is because i knew it didn't do much as far as acceleration is concerned. 3 local orgers have one and they admit it doesn't do crap. Old news...next...

 

How about the thought that the weight loss cause a loss of inertia...plus I dont see how spinning tires could justify anything,mine is auto and from a stop if I mash it I can spin tires way longer than I want to,and thats with brand new 17" rubbers on...Im not saying that the UDP and or flywheel doesnt do anything as I dont have either of them but I would think saying the lighter weight of the two cant justify more power,I would think the loss of inertia would counteract any gain.

 

if its spinning its tires, that means that they aren't gripping enough, meaning too much power is going to them and you need better tires. in otherwords, with better tires, you would get less wheelspin and more hookup

edit: i noticed a bigger gain once the ecu relearned, because i reset it while doing both of these mods

 

I don't agree with you either. Quicker revs, doesn't mean a faster car. Your engine isn't going to carry as much momentum, and you'll hafta over-rev it to get it going. UDP's are a waste of time.

 

Without a before/after dyno we have no way of knowing either way. A UDP would drive accessory belts slower and should technically rob the engine of less torque.

 

Now i know you're full of it. What exactly did the ECU have to relearn??

Oh yea...i'm still waiting for a response to my post...

 

Yeah the ECU shouldn't have to relearn crap, but he did say he reset it...

 

Lol,dude I dont mean no harm or anything and although I dont claim to be an expert inUDP's and flywheels I certainly understand how and why wheel spin occurs. You said in your first post that you can spin the tires all the way through first,then when I say my car does that,even though I'd rather it not obviously,you tell me its my tires,like I'm running $49 pep boy specials. Are you doing all this spinning with slicks? Because just how much grip is achievable on paved city streets?All I was saying,is even without a UDP or a lightened flywheel,the max,even in its automatic form with very good tires will spin the wheels heavily when floored from a stop on any street surface Ive driven on. I just dont understand how YOU equated wheel spin to gained power thru your UDP/flywheel setup.

 

ok i will admit that i dont have experience with JUST the UDP, although, when i installed it, along with the flywheel, i could tell a difference between just the flywheel and the UDP. it did help. his question was does it help, not how much does it help

 

think of it this way. when your ecu is reset it has to readjust to EVERYTHING. im not saying it helped with UDP and flywheel. but it had to adjust to the ypipe, altitude, and fuel grade, etc... then i could tell the difference, once i got back to ground zero. the ecu always has to relearn to get back to where it started before you reset.

edit: said the same thing twice

 

i have some michilins dont know what kind, but they are A traction rating, they do make AA traction rating, and yes, i do know they test the traction in wet pavement, not dry. but just food for thought

edit: i went back to ohio to visit some old friends, when i was there it was much easier to spin my tires on certain roads, so i would assume there pavement sucks, aka: not all roads provide as much grip as others

 

btw, nismo, im not trying to start an arguement, just an intelligent debating

 

do the UDP's that you are mentioning have a harmonic balancer, like the stock one has? if not, then you could damage the engine over time in any car(from what I have heard).

 

I'm sure there is a very small gain, there's no way around that. But my point is that the gain is negligible and not worth the expense.

 

Says who?

10frijoles

 

Yea thats what I'm saying..Im running 225/55-17 Goodyear Eagle F1's and still on nearly any street if I mash the pedal from a stop,the tires spin way more than I would like. I'm not saying the UDP/flywheel does nothing,although i feel personally that the gains would negligible,but to equate power to wheel spin I felt was a poor way to argue the gains of such a setup

 

the guy on here who did the tests using different fuel grades, trying to prove he got better mileage with 89 instead of 93. i remember him mentioning after about a tankfull the ecu relearned and mileage leveled out... does anyone have that link?

 

yea on one of the locals guys nismo be talkin bout. I say dont get it! if i had the chance to get it again i will save the money for something else. all it does is lower ur voltage at idle and dosnt let your a/c cool 100% on idle. also u gotta deal with getting the right belt, and then u gotta change it again because the one u got slips, so u gotta drive around and look for a good quality one. its just crap.

 

man you're not a very smart dude at all.. argue nismology=

 

what d'ya have a G35 ecu in your car lmao?..

 

Want more revs and faster acceleration? Get smaller tires.

 

Can someone please find the exponential rotational weight graph about lightened flywheels ... that would solve all.