Notices
General Technical
Sponsored by:
Sponsored by: CARiD

When changing pulleys....

Thread Tools
 
Search this Thread
 
Old 08 November 2006 | 03:08 PM
  #1  
Neilo's Avatar
Neilo
Thread Starter
Scooby Regular
 
Joined: Jul 2003
Posts: 5,734
Likes: 0
From: Behind the wheel of a Time Attack R33 GTR
Default When changing pulleys....

i see that most come as "sets" consisting of crank pulley, alternator pulley etc....

would it be detrimental if only the lighter crank pulley was fitted?
Old 08 November 2006 | 03:35 PM
  #2  
Optical Race's Avatar
Optical Race
Scooby Regular
 
Joined: Sep 2006
Posts: 800
Likes: 0
Default

Does'nt the Stock pully have some sort of Dynamic balancer/Damper in the middle in the form of a rubber ring which helps to prevent vibration going into the crank bearings etc.
Old 08 November 2006 | 03:36 PM
  #3  
Neilo's Avatar
Neilo
Thread Starter
Scooby Regular
 
Joined: Jul 2003
Posts: 5,734
Likes: 0
From: Behind the wheel of a Time Attack R33 GTR
Default

something along those lines yes, but to my knowledge it has those due to its own weight. Lighter ones do not suffer the same affliction...(apparently)
Old 08 November 2006 | 04:46 PM
  #4  
Optical Race's Avatar
Optical Race
Scooby Regular
 
Joined: Sep 2006
Posts: 800
Likes: 0
Default

Okay mate well in answer to your first question I cant see there being a problem then as you can buy them on their own and they are the heaviest pulley.

Regards

Chris
Old 08 November 2006 | 11:57 PM
  #5  
harvey's Avatar
harvey
Former Sponsor
iTrader: (48)
 
Joined: Mar 2001
Posts: 10,419
Likes: 1
From: Darlington
Default

Having run lightweight pulleys on a number of Scooby engines I can foresee no problem and replacing the crank pulley on its own is not an issue.
Old 08 November 2006 | 11:58 PM
  #6  
harvey's Avatar
harvey
Former Sponsor
iTrader: (48)
 
Joined: Mar 2001
Posts: 10,419
Likes: 1
From: Darlington
Default

BTW. some aftermarket light weight pulleys do NOT have a timing mark.
Old 09 November 2006 | 12:11 AM
  #7  
Dspeed's Avatar
Dspeed
Scooby Regular
 
Joined: Aug 2003
Posts: 1,027
Likes: 0
Default

Originally Posted by harvey
BTW. some aftermarket light weight pulleys do NOT have a timing mark.
But you wouldnt need one if you were just replacing the exernal ones would you or is the mark still used from the crank for further set up?
Old 09 November 2006 | 08:20 AM
  #8  
MaDaSS's Avatar
MaDaSS
Scooby Regular
 
Joined: Aug 2004
Posts: 2,086
Likes: 0
From: Nottingham
Default

Would there still be more benefit from me running light weight pulleys as i have a lightened flywheel now?
I noticed a big difference with the flywheel changed.
Just wondering if the pulleys would make any noticable change?
And also, would it affect the tickover or running of the car?
Thanks.
Old 09 November 2006 | 08:32 AM
  #9  
hmhaga's Avatar
hmhaga
Scooby Regular
 
Joined: Jul 2001
Posts: 326
Likes: 0
From: Telemark, Norway
Default

I have had a Perrin lightweight pulley (0,66 kg vs 2,4 kg) on my car the last 80.000 kilometers (49.700 miles). No problems, lots of track day usage. To notice any major improvement, you have to combine it with a lightweight flywheel. It does not affect the tickover.

Last edited by hmhaga; 09 November 2006 at 08:34 AM.
Old 09 November 2006 | 09:35 AM
  #10  
harvey's Avatar
harvey
Former Sponsor
iTrader: (48)
 
Joined: Mar 2001
Posts: 10,419
Likes: 1
From: Darlington
Default

But you wouldnt need one if you were just replacing the exernal ones would you or is the mark still used from the crank for further set up?
If you are mapping the car you would use the pulley mark to confirm what you were seeing on your laptop was what was actually happening on the car.

Removing weight from the opposite end of the crank is probably a good idea.
I doubt you would actually feel any difference however.
Classic O/E flywheels are generally 10.7 or 12.2 kgs. and can be machined to 7-8 kg quite easily. Best that they are balanced. I don't have a New Age here to weigh but they are certainly heavier on the six speed.
After market are usually between 4 and 6 Kg.
I think there are better things to spend the money on, rather than an after market flywheel unless it is relatively cheap and the box or engine are out in any case.

Tickover will probably not be affected although it could be more sensitive and require a small mapping change.
For the first day or two you may stall an odd time while your technique of driving off adjusts to the reduction in inertia.
If you do drag starts with a light flywheel, much more precision is required in your launch technique to avoid bogging down.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
KAS35RSTI
Subaru
27
04 November 2021 07:12 PM
Sam Witwicky
Engine Management and ECU Remapping
17
13 November 2015 10:49 AM
Ganz1983
Subaru
5
02 October 2015 09:22 AM
IAN WR1
ScoobyNet General
8
28 September 2015 08:14 PM
shorty87
Other Marques
0
25 September 2015 08:52 PM



Quick Reply: When changing pulleys....



All times are GMT +1. The time now is 02:19 PM.