Under Drive Pulleys...?

JAYNO20 · 08-26-2012, 01:47 PM

I have read through a few threads here and I can't see a clear yes or no as to whether these things are ok to run. I don't have a huge system, and the car is stock. Just wanting to free up as many horses as possible. What are the negatives to running a UDP?

JAYNO20 · 08-27-2012, 03:33 PM

Bump...

PharmDZ · 08-27-2012, 03:36 PM

I too am having trouble deciding on whether I'll be getting pulleys or not. It seems like they aren't very detrimental to the accessories, but I also haven't seen too many (if any?) dyno results posted along with each set of pulleys these companies are putting out. I'd like to see some hard data and hear people chime in who have them installed.

JAYNO20 · 08-27-2012, 03:46 PM

Quote:

Originally Posted by PharmDZ

I too am having trouble deciding on whether I'll be getting pulleys or not. It seems like they aren't very detrimental to the accessories, but I also haven't seen too many (if any?) dyno results posted along with each set of pulleys these companies are putting out. I'd like to see some hard data and hear people chime in who have them installed.

Yeah I wanna stay N/A and would like to get as much power as possible. So if these help without hurting anything I will be all over it.

VDC_OFF · 08-27-2012, 03:51 PM

I have a friend who is running the NST ones in his 350Z and convinced me to buy them after feeling gains throught the powerband with his butt dyno. Said it was night and day. Im just waiting for NST to get some in stock, then Ill try to get a before and after dyno.

As far as safeness, the NST thread explains that they have never had any issues with pullies getting welded to the crank and never had problems with harmonic balance issues.

JAYNO20 · 08-27-2012, 04:01 PM

Quote:

Originally Posted by VDC_OFF

I have a friend who is running the NST ones in his 350Z and convinced me to buy them after feeling gains throught the powerband with his butt dyno. Said it was night and day. Im just waiting for NST to get some in stock, then Ill try to get a before and after dyno.

As far as safeness, the NST thread explains that they have never had any issues with pullies getting welded to the crank and never had problems with harmonic balance issues.

Ok now we are getting somewhere! Any extra info?

Nut_N_Much · 08-27-2012, 07:08 PM

Yep, NST

... We have been waiting for a month now

.. Can't wait to get them on

.

I looked at Stillen, also some pulleys on ebay Unorthodox Racing Crank Pulley Nissan 350z 370z GTR G37 | eBay GlockWorks put one on his car Unorthodox Racing Lightweight Crank Pulley

Stillen and NST R&D is top notch. I went with NST because they sell kits for a butt load of cars, they have long history in racing.

kcquinn49 · 08-27-2012, 08:13 PM

I've read the threads here and researched at each vendor's site and at other links found on google. I have friends that have gone this way on other cars, e.g. dodge charger. I can't because I am in a lease.

When I buy out the lease I will definately buy as many of the lightweight pulleys as there are. Unorthodox has the crank, idler, and alternator pulleys for the 370z. NST has crank and alternator pulleys.

Unorthodox claims about 10-12 WHP gain for the underdrive crank pulley alone, with 15% of that being contributed to the 20% underdrive. So the OEM size lightweight crank pulley would be 8-10 vs. 10-12 WHP. They also claim another 1-2 WHP for each of the other pulleys, idler and alternator.

PharmDZ · 08-27-2012, 10:30 PM

Did they have anything to back that up Kcquinn?

SS_Firehawk · 08-28-2012, 10:32 AM

NST Pulleys are awesome. Better throttle response, gas mileage, rev matching is faster, it makes power ALL the way through the rev range, and it's inexpensive. It's one of my favorite mods. It's worth a good 7-10 whp everywhere. Pair it with a light flywheel and that's a slice of heaven.

BTW, no issues what so ever and that's with about 8k miles on them. The last couple pages of the NST pulley thread, I have A LOT of info on my experience with them.

XwChriswX · 08-28-2012, 10:35 AM

I've had NST Pulleys on for over a year 10k+ mi, and have had zero problems.

Dyno feel doesn't really change, but I do notice the fact that the engine revs much faster and smoother... Like there's 'less' of a strain to do so. Granted changes are minute and can be attributed to seeing what you want to see, but it's noticeable to me.

The primary concern comes down to how they're installed. If they are installed correctly by a competent technician, then you'll be fine. If not, then you'll have problems. So trust your mechanic or don't get them.

kcquinn49 · 08-28-2012, 10:59 AM

Quote:

Originally Posted by PharmDZ

Did they have anything to back that up Kcquinn?

I've seen dyno comparisons. I just can't locate them right now. Those were for NST pulleys. I can't access the unorthodox racing site for some reason. You have to google and find retailers that carry their products. There is an NST thread here that I believe has dyno charts.

For the accessory pulleys I've not seen any dynos, and who would expect a dyno to show a 1-2 WHP gain anyway? Maybe if all of them were changed you could see the difference.

370Z JT · 08-30-2012, 02:32 AM

I did a before after dyno on the NST. Gained 7-10 hp.

SS_Firehawk · 08-30-2012, 11:47 AM

Here is the dyno results after the install

kcquinn49 · 08-30-2012, 01:29 PM

Quote:

Originally Posted by 370Z JT

I did a before after dyno on the NST. Gained 7-10 hp.

Was this the two pulley set with under drive crank pulley?

08-26-2012, 01:47 PM	#1 (permalink)
JAYNO20 Track Member Join Date: Mar 2012 Location: Pittsburgh, PA Posts: 802 Drives: 2010 370Z Nismo Rep Power: 14	Under Drive Pulleys...? I have read through a few threads here and I can't see a clear yes or no as to whether these things are ok to run. I don't have a huge system, and the car is stock. Just wanting to free up as many horses as possible. What are the negatives to running a UDP? __________________ 2010 Solid Red NISMO #0334 - SOLD 2014 Red Hot Camaro ZL1

08-27-2012, 03:33 PM	#2 (permalink)
JAYNO20 Track Member Join Date: Mar 2012 Location: Pittsburgh, PA Posts: 802 Drives: 2010 370Z Nismo Rep Power: 14	Bump... __________________ 2010 Solid Red NISMO #0334 - SOLD 2014 Red Hot Camaro ZL1

08-27-2012, 03:51 PM	#5 (permalink)
VDC_OFF A True Z Fanatic Join Date: Aug 2011 Location: Houston (Pearland) Age: 44 Posts: 1,205 Drives: 2011 370Z M6 Rep Power: 16	I have a friend who is running the NST ones in his 350Z and convinced me to buy them after feeling gains throught the powerband with his butt dyno. Said it was night and day. Im just waiting for NST to get some in stock, then Ill try to get a before and after dyno. As far as safeness, the NST thread explains that they have never had any issues with pullies getting welded to the crank and never had problems with harmonic balance issues. __________________ DRIFTING JOURNAL \| Follow me on Instagram \| Facebook \| Houston Halos

08-27-2012, 07:08 PM	#7 (permalink)
Nut_N_Much A True Z Fanatic Join Date: Dec 2011 Location: Pensacola Florida Posts: 1,696 Drives: Awesome Car Rep Power: 26	Yep, NST ... We have been waiting for a month now.. Can't wait to get them on. I looked at Stillen, also some pulleys on ebay Unorthodox Racing Crank Pulley Nissan 350z 370z GTR G37 \| eBay GlockWorks put one on his car Unorthodox Racing Lightweight Crank Pulley Stillen and NST R&D is top notch. I went with NST because they sell kits for a butt load of cars, they have long history in racing. __________________ Did new cool science stuff to the car !!! http://www.the370z.com/mazoc/99606-z...y-14-17-a.html http://www.the370z.com/diy-section-d...-w-videos.html

08-28-2012, 10:32 AM	#10 (permalink)
SS_Firehawk Premium Member Join Date: Oct 2011 Location: Tampa Posts: 4,142 Drives: 13' Magma Red Nismo Rep Power: 7334	NST Pulleys are awesome. Better throttle response, gas mileage, rev matching is faster, it makes power ALL the way through the rev range, and it's inexpensive. It's one of my favorite mods. It's worth a good 7-10 whp everywhere. Pair it with a light flywheel and that's a slice of heaven. BTW, no issues what so ever and that's with about 8k miles on them. The last couple pages of the NST pulley thread, I have A LOT of info on my experience with them. __________________ Old Car:GTM TSC'd 550whp / 410lbft tq @ 11.88PSI New Car: Under Construction

08-27-2012, 03:36 PM	#3 (permalink)
PharmDZ Track Member Join Date: Jul 2012 Location: New Jersey Posts: 997 Drives: 11 Nissan 370Z BS M6 Rep Power: 13	I too am having trouble deciding on whether I'll be getting pulleys or not. It seems like they aren't very detrimental to the accessories, but I also haven't seen too many (if any?) dyno results posted along with each set of pulleys these companies are putting out. I'd like to see some hard data and hear people chime in who have them installed.

08-27-2012, 08:13 PM	#8 (permalink)
kcquinn49 Base Member Join Date: Dec 2011 Location: Indiana Posts: 86 Drives: 2011 370Z Coupe Rep Power: 249	I've read the threads here and researched at each vendor's site and at other links found on google. I have friends that have gone this way on other cars, e.g. dodge charger. I can't because I am in a lease. When I buy out the lease I will definately buy as many of the lightweight pulleys as there are. Unorthodox has the crank, idler, and alternator pulleys for the 370z. NST has crank and alternator pulleys. Unorthodox claims about 10-12 WHP gain for the underdrive crank pulley alone, with 15% of that being contributed to the 20% underdrive. So the OEM size lightweight crank pulley would be 8-10 vs. 10-12 WHP. They also claim another 1-2 WHP for each of the other pulleys, idler and alternator.

08-27-2012, 10:30 PM	#9 (permalink)
PharmDZ Track Member Join Date: Jul 2012 Location: New Jersey Posts: 997 Drives: 11 Nissan 370Z BS M6 Rep Power: 13	Did they have anything to back that up Kcquinn?

08-28-2012, 10:35 AM	#11 (permalink)
XwChriswX WFLYIDNNE Join Date: Jul 2009 Location: In The Fastlane Posts: 50,648 Drives: 02 GDB WRX Rep Power: 451	I've had NST Pulleys on for over a year 10k+ mi, and have had zero problems. Dyno feel doesn't really change, but I do notice the fact that the engine revs much faster and smoother... Like there's 'less' of a strain to do so. Granted changes are minute and can be attributed to seeing what you want to see, but it's noticeable to me. The primary concern comes down to how they're installed. If they are installed correctly by a competent technician, then you'll be fine. If not, then you'll have problems. So trust your mechanic or don't get them. __________________ Bonnie - Stage 2, Audio build coming this fall! R.I.P. Abby 3/29/10 - 3/30/14

08-30-2012, 02:32 AM	#13 (permalink)
370Z JT A True Z Fanatic Join Date: Jan 2010 Location: United States Posts: 2,905 Drives: 370Z PW 7AT Rep Power: 378	I did a before after dyno on the NST. Gained 7-10 hp. __________________ Click for My Journal Top Secret \| EVO-R \| Fujimura Auto \| Shine Auto \| Seibon \| MRWorks \| Swift \| SPC \| SSR \| UpRev \| Project Kics \| NST \| Titek \| Eibach \| Nismo \| Whiteline \| Quaife \| Invidia \| Fly1 \| CF Element \| Carbon Signal

08-30-2012, 11:47 AM	#14 (permalink)
SS_Firehawk Premium Member Join Date: Oct 2011 Location: Tampa Posts: 4,142 Drives: 13' Magma Red Nismo Rep Power: 7334	Here is the dyno results after the install __________________ Old Car:GTM TSC'd 550whp / 410lbft tq @ 11.88PSI New Car: Under Construction

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