jim s3
Registered User
has anyone got any on their car if so did you notice any difference thinking about getting some...
umder drive pullys
- Thread starter jim s3
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I've heard stories of issues with air con and battery charging if in traffic at low revs.
Also concerns about removing the harmonic balancer which is designed to cancel out harmful engine vibration. Though this may just be theory.
Also concerns about removing the harmonic balancer which is designed to cancel out harmful engine vibration. Though this may just be theory.
jim s3
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Ess_Three
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I'm not so sure...
Bling, yes. To a point.
Reducing rotating mass of the engine makes for a more lively engine...especially a high revving NA engine.
We fitted underdrive pullys to a 2.9 VR6, and added a light flywheel...and it revs far sweeter than standard.
Same theory for reducing valvegear losses (lightweight lifters, hollow cams, Titanium retainers etc) it's all about reducing rotating mass, to improve throttle response and pick up. Hence the next step for the VR is lightweight valvegear with the new cams.
Underdrive pullys should do this because they are lighter...
Reducing drag on an alternator/power steering pump will also reduce parasitic losses.
So, they should work...and offer some positives...but thare may well be down sides for road card, such as the battery not charging at idle properly, etc.
The theory is sound...and if you are reducing weight and chasing ever last BHP...then maybe they are a good idea.
I've noticed no downsides to then thus far.
but I wouldn't expect much by way of gains on a fully equipped road car.
Bling, yes. To a point.
Reducing rotating mass of the engine makes for a more lively engine...especially a high revving NA engine.
We fitted underdrive pullys to a 2.9 VR6, and added a light flywheel...and it revs far sweeter than standard.
Same theory for reducing valvegear losses (lightweight lifters, hollow cams, Titanium retainers etc) it's all about reducing rotating mass, to improve throttle response and pick up. Hence the next step for the VR is lightweight valvegear with the new cams.
Underdrive pullys should do this because they are lighter...
Reducing drag on an alternator/power steering pump will also reduce parasitic losses.
So, they should work...and offer some positives...but thare may well be down sides for road card, such as the battery not charging at idle properly, etc.
The theory is sound...and if you are reducing weight and chasing ever last BHP...then maybe they are a good idea.
I've noticed no downsides to then thus far.
but I wouldn't expect much by way of gains on a fully equipped road car.
jim s3
Registered User
tell you what then i will go ahead and get some and post the results when they are fitted and my car is fixed.. as the belt has lost a few teath lol
