Dynamometer Results & Comparisons Dyno Records | Dyno Discussion | Dyno Wars

UD pulley worth the cost?

Thread Tools
 
Search this Thread
 
Old 10-14-2011, 07:46 PM
  #1  
On The Tree
Thread Starter
iTrader: (2)
 
little_chewy_69's Avatar
 
Join Date: Jan 2007
Posts: 182
Likes: 0
Received 0 Likes on 0 Posts

Default UD pulley worth the cost?

i am looking to breach 450 rwhp and was wondering what are the average gains of a 25% UD pulley...or what did you guys gain?
Old 10-14-2011, 07:48 PM
  #2  
On The Tree
 
sergo's Avatar
 
Join Date: Jul 2008
Location: Las Colinas, TX
Posts: 125
Likes: 0
Received 0 Likes on 0 Posts

Default

right at about 5hp is what you can expect. every graph i've seen of before and after show about 5hp across the entire range.
Old 10-14-2011, 08:06 PM
  #3  
10 Second Club
iTrader: (1)
 
mike c.'s Avatar
 
Join Date: Mar 2002
Location: mi
Posts: 4,033
Likes: 0
Received 2 Likes on 2 Posts

Default

I don't get why so many people only care that they have a number. I have been on dyno jets and mustang dynos and none were the same reading. If you are on a jet,go to a stang dyno and watch your number drop. It don't mean your car is slower. I gained just over a tenth with the ASP pulley. I tried the slp pulley and it was way heavier. If your looking to go faster get the pulley. if you want a number remove the airfilter and the belt as you dyno. I seen this gain 12hp on a guys car.
Old 10-14-2011, 08:30 PM
  #4  
TECH Regular
iTrader: (1)
 
reeperz28's Avatar
 
Join Date: Oct 2010
Location: Amarillo Tx
Posts: 496
Likes: 0
Received 0 Likes on 0 Posts

Default

If its time for new belts its an expensive good excuse to get it ha
Old 10-14-2011, 08:39 PM
  #5  
TECH Enthusiast
iTrader: (13)
 
z28241's Avatar
 
Join Date: Sep 2006
Location: western new york
Posts: 716
Likes: 0
Received 1 Like on 1 Post

Default

I think its a good supporting mod...if u want to equate 5-10 hp or over a tenth for 125 bucks..well these days thats worth it..+1 here

Last edited by z28241; 10-14-2011 at 08:47 PM.
Old 10-14-2011, 08:59 PM
  #6  
11 Second Club
iTrader: (5)
 
Camaro Z's Avatar
 
Join Date: Sep 2005
Location: Monroe, Iowa
Posts: 1,024
Likes: 0
Received 0 Likes on 0 Posts

Default

Can't hurt
Old 10-14-2011, 10:51 PM
  #7  
TECH Senior Member
iTrader: (9)
 
Tainted's Avatar
 
Join Date: Mar 2006
Location: Indianapolis
Posts: 8,425
Likes: 0
Received 2 Likes on 2 Posts
Default

Less rotational mass the better
Old 10-15-2011, 04:35 AM
  #8  
On The Tree
Thread Starter
iTrader: (2)
 
little_chewy_69's Avatar
 
Join Date: Jan 2007
Posts: 182
Likes: 0
Received 0 Likes on 0 Posts

Default

im not saying i must have 450RWHP it's just a goal you have to shoot for something right...but thanks for the info guys.
Old 10-17-2011, 07:55 AM
  #9  
TECH Addict
iTrader: (21)
 
blk/slvr02ss's Avatar
 
Join Date: Dec 2006
Location: Port Saint Lucie,Florida
Posts: 2,767
Likes: 0
Received 1 Like on 1 Post
Default

Yes it is worth it for the Money and i have seen a 8 hp gain on one of my cars .
Old 10-18-2011, 11:05 AM
  #10  
Launching!
iTrader: (2)
 
66 BADBOY's Avatar
 
Join Date: Aug 2007
Location: MI
Posts: 250
Likes: 0
Received 2 Likes on 2 Posts

Default

What if you are only running a water pump and alternator? (no power steering, no air conditioning)? Probably doesn't have as much of an improvement, right?
Old 10-18-2011, 11:46 AM
  #11  
TECH Senior Member
iTrader: (9)
 
Tainted's Avatar
 
Join Date: Mar 2006
Location: Indianapolis
Posts: 8,425
Likes: 0
Received 2 Likes on 2 Posts
Default

Probably not but even still the less rotational mass the better
Old 10-18-2011, 11:59 AM
  #12  
TECH Fanatic
iTrader: (4)
 
Bill00Formula's Avatar
 
Join Date: Nov 2001
Location: West Palm Beach, Fl
Posts: 1,066
Likes: 0
Received 11 Likes on 9 Posts

Default

I guess it all depends on how you look at it. There are only a couple of mods that make significant differences by themselves but they all add up. For me it was worth it. Increase in power with no downside, at least that I've encountered.
Old 10-19-2011, 04:36 AM
  #13  
TECH Senior Member
iTrader: (4)
 
vettenuts's Avatar
 
Join Date: Jul 2004
Location: Little Rhody
Posts: 8,092
Likes: 0
Received 9 Likes on 9 Posts

Default

Stay away from ASP.
Old 10-19-2011, 05:21 AM
  #14  
TECH Enthusiast
iTrader: (5)
 
NVUSZ28's Avatar
 
Join Date: Apr 2011
Location: The Great State of Texas
Posts: 561
Likes: 0
Received 0 Likes on 0 Posts
Default

It's one of the first mods that I suggest to people when they want to start modding. It's a Must, IMO. It's really a no brain-er. You shed a tiny amount of weight, and gain about 5-8 hp, on a 250$ part.
Old 10-19-2011, 06:13 AM
  #15  
Launching!
iTrader: (2)
 
66 BADBOY's Avatar
 
Join Date: Aug 2007
Location: MI
Posts: 250
Likes: 0
Received 2 Likes on 2 Posts

Default

I never thought it was a matter of weight?

I always thought they marketed them as "underdrive" because it acts as a smaller "gear" for the belt system. Kinda like putting your 10 speed bike in 1st.....much easier to pedal.

To me, if it was a HP increase due to weight, then these would be marketed as "lightweight" pulleys.
Old 10-19-2011, 06:15 AM
  #16  
11 Second Club
iTrader: (5)
 
Stippy17's Avatar
 
Join Date: May 2009
Location: Pittsburgh
Posts: 350
Likes: 0
Received 0 Likes on 0 Posts
Default

I just installed an ASP Pulley on my car last month. No compaints so far. My car dynoed @ 398whp and has seen 11.76 @ 115 so I should be around 405whp and should be able to get an 11.6 pass now.

Its worth the money in my opinion.
Old 10-19-2011, 11:41 AM
  #17  
TECH Senior Member
iTrader: (9)
 
Tainted's Avatar
 
Join Date: Mar 2006
Location: Indianapolis
Posts: 8,425
Likes: 0
Received 2 Likes on 2 Posts
Default

Some pulleys are marketed as lightweight. I believe its in the same effect as an aftermarket or lighter flywheel. Less mass to spin and the easier to transfer power.
Old 10-19-2011, 03:30 PM
  #18  
TECH Enthusiast
 
Austinma62's Avatar
 
Join Date: Nov 2008
Location: Saint Joseph, MO
Posts: 525
Received 3 Likes on 3 Posts

Default

I always thought being 25% underdrive meant it would spin all your accesories at 75% of there normal speed. That in which is were you would see your gains, less pull on the crank=more power!
Old 10-19-2011, 03:52 PM
  #19  
11 Second Club
iTrader: (18)
 
thunderstruck507's Avatar
 
Join Date: Mar 2008
Location: Northwest AR
Posts: 8,357
Received 21 Likes on 17 Posts

Default

I gained a tenth with mine. Got it used on ebay for $120 shipped.
Old 10-20-2011, 07:16 PM
  #20  
10 Second Club
iTrader: (1)
 
KC&97TA's Avatar
 
Join Date: May 2010
Location: Dirty J'Ville
Posts: 123
Likes: 0
Received 0 Likes on 0 Posts
Default

I put an ATI on mine, 10% UD on accessories and AC, for many reasons. SFI approved being the biggest, noticeable difference in adding to low end tq, just an added comfort to have a better balancer on a 4" bore / 4" stroke engine.

I added the ballancer with a 100mm MAF / 104 Lid, so the gains of 12hp/9tq on peak sound insignificant for the $1k of parts, labor, tune... gains of 12-15 rwtq in the lower RPM's are obvious when comparing the graph.




All times are GMT -5. The time now is 09:36 AM.