We have just finshed making our Ultra-light weight Stock and undedrive crank pulleys for all classic models,

For only £50 these are made from he30 alloy - unlike most cheap imports , these are very strong and weigh 350 grams and stock @ 545 grams, compared to stock cast iron pulleys @ 2165grams!

And they say for every 1lb you remove from the crankshaft a average of 2.7hp in gained ,

If anyone can find lighter pulleys i'll give them a free one!

Pulleys are listed on My WRX the home of WRX cars


Any questions please fire away!

Chris
CDF Racing, performance pulleys

 

just 2 questions mate,

1. who is "they" that say every 1lb gains 2.7hp and what formula are they using.
2. can you show any research that these crank pulleys still eliminate/obsorb harmonic vibration, and if not then can you tell me its safe.

 

yeah i second that come on let us know im curious to the durability aspect of the item .

 

Hi ,

Will answer soon!

How to I upload a photo from my destop?

Sorry im new


chris

 

sign up to photobucket.com and get yourself a free account.
Then just link from your account to your post.

 

Cheers peanuts.,



Here are the two pulleys that are fresh off our Cnc's this week.

One is Stock size ( 133mm) and one in the underdriven size ( 104mm)

http://i140.photobucket.com/albums/r...g/DSC00169.jpg


Now to answer some questions , now unorthodoxracing have done many tests on these type's of pulleys and have it in black and white to prove that these increase performance, 10bhp in fact on there lightweight crank pulley ( Our pulleys are now lighter than there's )


Here is there dyno chart ..

http://i140.photobucket.com/albums/r...g/dyno_wrx.jpg


Now regarding if there are safe or not, the answer is yes- now I know your thinking I would say that, but we have sold many lightweight alloy pulleys and have never had one complaint- in fact the only ones that I have ever heard to crack have been the stock steel ones,

Our pulleys are made from He30 ally which is very strong,

The other questions people ask are about the underdrive pulley and how they don't see the point of it because they require a longer belt causing the crank shaft to run slower- which is fair enough! So the best bet is to use a lightweight stock size pulley , Now our new one now weigh the same as the underdrive pulleys you will find on ebay , getting the best of both worlds - But warning, sellers selling the underdrive crank pulleys on ebay may come into trouble soon as we have brought a underdrive pulley from ebay in the past and the vee's in the top of the pulleys are NOT CORRECT , what I mean is the pitch and depth for the belt to sit in is WRONG!
If you don't believe me i can email photo's , If you have one of these on your car Please replace it!

I would gladly exchange it will one of ones- before the belt snaps,. Yes it may not wear/ snap for a while but it will! ,

Hope I have answered your questions ... Cheers

 

not really mate no, these do look mint and i really want one but this is my problem, the original crank pulley was designed to take out vibration from the crank by its weight and the fact it has a rubber insulator built in, i can not see how your crank pulleys would do this!!!

fill me with confidence please then i can buy a set hehe

 

Hi ,

That's fair enough, i'd be the same if i was to have stuff fitted onto my car,

Yes the stock steel pulleys do have the rubber part in the middle of the pulley to take out the vibration, and that is because they are a fair old heavy lump! These lightweight one's simply don't need them cause they are too light too vibrate..

Now we have fitted the one to one of our customers in the past as he was worried about the same thing, Haven't got any photos of the pulley but could get you the guys email, Honestly though- there is no need for it but for peace off mind we can install them to our other type's of stock pulleys ...

http://i140.photobucket.com/albums/r.../goldcrank.jpg


These are a copy of the stock pulley in ally but a little heaver than our new design, around 900grams,

Chris

 

Puma Race Engines Technical Guide - Lightening Flywheels

Same principle, but I haven't heard it expressed that way before.