Neilo

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?

Optical Race

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.

Neilo

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)

Optical Race

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

harvey

iTrader: (48)

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.

harvey

iTrader: (48)

BTW. some aftermarket light weight pulleys do NOT have a timing mark.

Dspeed

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?

MaDaSS

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.

hmhaga

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.

harvey

iTrader: (48)

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.