Forced Induction Superchargers | Turbochargers | Intercoolers

Idler Pulleys

Thread Tools
 
Search this Thread
 
Old 07-17-2011, 08:44 PM
  #1  
TECH Resident
Thread Starter
iTrader: (7)
 
kyoytey1693's Avatar
 
Join Date: Jan 2009
Location: tulsa
Posts: 805
Received 6 Likes on 6 Posts

Default Idler Pulleys

I am going to change the idler pulley location on my Magnacharger setup to give me some more belt wrap. I just need a small pulley maybe 1-2" in diameter so I can tuck it in close to the blower pulley and miss the intake.

Does anyone know where to find idler pulleys in different sizes? I need one that has a bearing in it. I'm sure Autozone has them but without knowing what year, make and model one comes on I dont know how they would ever find one.

Any ideas?
Old 07-18-2011, 08:29 AM
  #2  
UNDER PRESSURE MOD
iTrader: (19)
 
The Alchemist's Avatar
 
Join Date: Nov 2001
Location: Doylestown PA
Posts: 10,813
Received 13 Likes on 10 Posts

Default

Try sending a PM to Aster as he uses a small idler on his custom brackets for the procharger.
Old 07-18-2011, 08:59 AM
  #3  
9 Second Club
iTrader: (27)
 
Need_a_Camaro's Avatar
 
Join Date: Apr 2009
Location: Augusta, WV
Posts: 449
Likes: 0
Received 1 Like on 1 Post

Default

How will the idler attach? I used a DSM timing belt idler, and it worked perfectly. 30 bucks at NAPA.
Old 07-18-2011, 07:09 PM
  #4  
TECH Resident
Thread Starter
iTrader: (7)
 
kyoytey1693's Avatar
 
Join Date: Jan 2009
Location: tulsa
Posts: 805
Received 6 Likes on 6 Posts

Default

Originally Posted by Need_a_Camaro
How will the idler attach? I used a DSM timing belt idler, and it worked perfectly. 30 bucks at NAPA.
There is a bracket that the current idler is on under the intake. But the blower pulley is on the passenger side and the idler is on the drivers. I'm just going to drill another hole in the same bracket and install a smaller pulley and move it to the passenger side so I can tuck the belt in tighter around the blower pulley.

You guys did notice I'm running a Magnacharger not a Procharger right? Does that have any effect on your responses?
Old 07-18-2011, 07:53 PM
  #5  
UNDER PRESSURE MOD
iTrader: (19)
 
The Alchemist's Avatar
 
Join Date: Nov 2001
Location: Doylestown PA
Posts: 10,813
Received 13 Likes on 10 Posts

Default

I'm not familiar with how the magnacharger belt is routed, but you were asking for a source of small idler pullies, and I know Aster's bracket uses one.
Old 07-18-2011, 08:25 PM
  #6  
9 Second Club
iTrader: (27)
 
Need_a_Camaro's Avatar
 
Join Date: Apr 2009
Location: Augusta, WV
Posts: 449
Likes: 0
Received 1 Like on 1 Post

Default

Can you post a pic of the current pulley? It makes no difference to me what type of blower it is. If the pulley bolts to the bracket with a bolt through the bracket, the DSM pulley will work, and is 2".
Old 07-18-2011, 10:46 PM
  #7  
TECH Resident
Thread Starter
iTrader: (7)
 
kyoytey1693's Avatar
 
Join Date: Jan 2009
Location: tulsa
Posts: 805
Received 6 Likes on 6 Posts

Default

Cool. That's the answer I was looking for. I'll get some pics in a minute.
Old 07-18-2011, 11:03 PM
  #8  
TECH Resident
Thread Starter
iTrader: (7)
 
kyoytey1693's Avatar
 
Join Date: Jan 2009
Location: tulsa
Posts: 805
Received 6 Likes on 6 Posts

Default



This is the current idler. Its way too big and too far away from the blower pulley.



This is the blower pulley and you can see the braket a little better. You can't see the idler from this side and it's hard to tell the depth in the pic but I'm positive I can but a smaller idler on there and tuck the belt a little further around the pulley by just relocating the bolt hole.
Old 07-19-2011, 04:27 AM
  #9  
9 Second Club
iTrader: (27)
 
Need_a_Camaro's Avatar
 
Join Date: Apr 2009
Location: Augusta, WV
Posts: 449
Likes: 0
Received 1 Like on 1 Post

Default

I believe the DSM pulley would work for you. It's from a 90-92 Eclipse/Talon/Laser, timing belt idler pulley. It was about 30 bucks.
Old 07-19-2011, 02:18 PM
  #10  
TECH Resident
Thread Starter
iTrader: (7)
 
kyoytey1693's Avatar
 
Join Date: Jan 2009
Location: tulsa
Posts: 805
Received 6 Likes on 6 Posts

Default

I looked them up. It looks like its about the right size. I know a bolt goes through the middle but does it need a special washer to grip the bearing (kinda like the OEM's use), does it come with any hardware or is the fab work up to me?
Old 07-19-2011, 05:51 PM
  #11  
TECH Resident
Thread Starter
iTrader: (7)
 
kyoytey1693's Avatar
 
Join Date: Jan 2009
Location: tulsa
Posts: 805
Received 6 Likes on 6 Posts

Default

I did some more measuring... I'm going to have to have one that is 1" in diameter. I can sqeaze maybe just a little more than that in there but anything more hits the intake tube and relocating it isn't an option.

You say Aster may be able to make one? I think I can probably turn down a pulley at a friends shop, im just worried about a bearing.
Old 07-19-2011, 06:49 PM
  #12  
TECH Regular
iTrader: (9)
 
Aster's Avatar
 
Join Date: Sep 2005
Location: Austin, Tx
Posts: 459
Likes: 0
Received 1 Like on 1 Post

Default

My smallest idler is 1.75" in diameter, can't go any smaller. You're getting into cam bearings at that size. The standard automotive bearing is 40 mm diameter which is ~1.575". The bearings I use in my small pullies are 30mm with is 1.1811".

Depending on how wide your belt is you might be able to get a cam follower, but getting one that can handle the RPM will be tricky. Most I have seen are rated significantly lower than what it would see. A 1" diameter pulley at 6500 engine RPM is getting above 49000 RPM.
Old 07-19-2011, 07:21 PM
  #13  
TECH Resident
Thread Starter
iTrader: (7)
 
kyoytey1693's Avatar
 
Join Date: Jan 2009
Location: tulsa
Posts: 805
Received 6 Likes on 6 Posts

Default

I was worried about the rotating speed getting too high. I'm down for the smallest pulley you can make. Does it come with a bearing, bolt, those special washers/spacers to attach it, or am I on my own for that? Let me know how much. If that is as small as you can make one then I will just have to change my bracketry some.



Quick Reply: Idler Pulleys



All times are GMT -5. The time now is 05:01 PM.