lightweight pulleys

[chrisflorey]

Hi Everyone,

My name is Chris Florey and I run a engineering company in Rochester Kent called CDFRacing .

We have been making pulleys since 1988 and in 2005 we started making Lightweight pulleys for cars,

I got the idea after browsing on the internet one night and coming across some on Ebay .
After buy a couple of sets from Ebay we found that these were not made correctly at all, after looking into them we found out that they had been mass produced in China .

Checking some of these pulleys we found

1) They were running out a mile (not running true)
2) Made with a low quality Alloy ,
3) The vee's ( where the belt sits) were not made to the right depth or pitch,


So we decided to start making these pulleys correctly out the the best alloy in the Uk,


I am just working round myself round the owners clubs now as I can offer everyone great price's for these custom lightweight pulleys,

The idea behind replacing the front pulleys ( Crank , waterpump , alternator , power steering) is to put less energy on the crankshaft letting it spin more freely and therefor increasing Bhp , throttle response and Torque, + of course they look good!


What I can offer is great price's if we were to set up a group buy for these pulleys . If we were to make a one off set the average price would be around £180 , to have these made in larger quantities i.e a batch of 20 we can drop these prices by 30% maybe more as larger quantities allow us to put them on one of our Cnc's and not a manual lathe.


We have just finished on Scoobynet which went very well and we had nothing but good comments after. You can find the link to the group buy here http://bbs.scoobynet.com/group-buys-356/568811-amazing-savings-these-kits.html



If we don't currently hold stock on standard pulleys for your cars we would require samples maybe of someone's car or from a breakers,


Please let me know if this is of any interest to anyone , Im here to answer any questions you may have,

Please Pm me or contact me on info@cdfracing.co.uk


ADMIN : Please don't remove this post , please contact me and I will gladly pay for advertising

Thanks Chris



http://i140.photobucket.com/albums/r19/cdfracing/DSC00612.jpg


http://i140.photobucket.com/albums/r19/cdfracing/Eloksertedrev.jpg

[stuartturbo]

Right on me door step LOL
they do look nice
Shame i dont have the wedge

[Axeboy]

Looks good :)

[Paul C]

sounds good would of been more interested if i wasn't purchasing map ecu at present

[Kieran]

Hi Chris - Can you comment on the suitability of these pulleys for the V6 engines in our cars? I must admit I'm not sure, but I *think* our crank pulleys have harmonic balancers in them - I've read that lightweight crank pulleys are unsuitable in this scenario?

[chrisflorey]

Hi Chris - Can you comment on the suitability of these pulleys for the V6 engines in our cars? I must admit I'm not sure, but I *think* our crank pulleys have harmonic balancers in them - I've read that lightweight crank pulleys are unsuitable in this scenario?



Hi ,

Yes I have heard this .. People to worries about this, without the Rubber part in the pulley it will cause vibration and damage the crankshaft bearing,

I have only heard of this in one on a skyline, not one of my pulleys , It may of been just due to the fact that it was a poorly made pulley ,

The reason the harmonic balancr is in the stock pulley is because it is bloody heavy and yes if it didn't have it inside it would vibrate like mad - I personaly think it isn't required in the ally pulleys, But for piece of mind we can insert a rubber / plastic part to do the same job !



Any more question please fire away!

Chris www.cdfracing.co.uk

[bradc]

hell yeah go for it I'm keen. Does anyone know if 6a12's are the same? We could go in with the FTO guys.

[caishanvr4]

:thinking: mmmm

Im keen :happy:

[Kenneth]

I think I would be keen too. if we can get some shipped to NZ that could help with a group buy.

I Assume that they would be somewhat custom to our vehicles? if this is so, surely we could request slightly higher sides on the pullies? this could help significantly with the belt throwing we occasionally see (though a good pully may stop this anyway)

[chrisflorey]

Hi ,


Yes these can be made excatly how you want, We can make the flange side's bigger no problem ,

just let me know what engine's/years you have,


chris

[Nick Mann]

Most people on here have the 6A13 twin turbo. There is also the 6A13 non-turbo, a version of the 4G63 non-turbo and then several other random efforts! If you need more info, someone could probably help - just let us know.

[chrisflorey]

Most people on here have the 6A13 twin turbo. There is also the 6A13 non-turbo, a version of the 4G63 non-turbo and then several other random efforts! If you need more info, someone could probably help - just let us know.


Does anyone have any 6a13 pulleys laying around ? Even if anyone can get pic's posted I can quote for 10 kits ,

[Nick Mann]

Bear in mind that the 6A13 has two cams and the 6A13TT has four....

And sorry - I don't have any photos of the engine with the cam cover off but if you look at my car photos in my VBgarage, you will see most of the accessory belts pulleys. (Click on my user name, then select view Nick Manns car.)

[Davezj]

I have some pictures of the pulleys as i had my Cam belt changed recently. I was lucky i had it changed when i did, as you will see from my pictures.

I have not posted any pictures on here so i will have to learn how to do it. and resize them.

I will do it in my next post.

By the way the reason for the dodge belt is the water pump bearing failed leaked water then stopped but carried on colapsing. the belt gradually started running off the back of the water pump pulley, and the results you can see.

[Davezj]

http://www.clubvr4.com/forum/uploaded/2693/1171827225.jpg
http://www.clubvr4.com/forum/uploaded/2693/1171827195.jpg
http://www.clubvr4.com/forum/uploaded/2693/1171827172.jpg
http://www.clubvr4.com/forum/uploaded/2693/1171827141.jpg
http://www.clubvr4.com/forum/uploaded/2693/1171827089.jpg

These pics were taken for the cam belt but they show the 2 front bank pulleys and the rear bank are the same as the one on the left. Not sure why the front one is different.
Is the normal.
i can take more pics if required as my cam covers are still off. Let me know.

Cheers Dave

[Kieran]

Dave - that's VERY lucky! Good lord!:speechles

[chrisflorey]

http://www.clubvr4.com/forum/uploaded/2693/1171827225.jpg
http://www.clubvr4.com/forum/uploaded/2693/1171827195.jpg
http://www.clubvr4.com/forum/uploaded/2693/1171827172.jpg
http://www.clubvr4.com/forum/uploaded/2693/1171827141.jpg
http://www.clubvr4.com/forum/uploaded/2693/1171827089.jpg

These pics were taken for the cam belt but they show the 2 front bank pulleys and the rear bank are the same as the one on the left. Not sure why the front one is different.
Is the normal.
i can take more pics if required as my cam covers are still off. Let me know.

Cheers Dave


Those Cam gears look fine to make, we would have to check we have the cutter... we can make these in lightweight ally and also look and making them adjustable for a better performance gain!

chris

[Davezj]

I had the head gasket replaced when i got the water pump, tensioner, idoler, cam belt, cam shaft seals, etc, etc it cost me over a grand. but it could have been worse as you say. I got the car low loaded to the garage which i thougt was a must with the belt looking like that.

Cheers Dave

[zentac]

I should be able to strip all the cam gears and pully's off my old engine next week if that will help. Exactly which ones do you need?

[chrisflorey]

Hi,

Nice engine!

What ever pulleys you guys may be interested in ... CAM GEARS / ALTERNATOR PULLEYS / CRANKS / POWERSTEERING / WATERPUMP / TENSIONERS...

[Louis]

Those Cam gears look fine to make, we would have to check we have the cutter... we can make these in lightweight ally and also look and making them adjustable for a better performance gain!

chris


Hi, I changed my timing belt a couple of weeks ago, and I noticed that the very front exhaust cam pulley is different to the other three, see attached photo, I am not sure why this would be (unless one of mine has been changed for some reason, but that is doubtful). I am sure the other three are the same, as at first I thought it was possibly adjustable and looked at the rear head, but the two pulley on the rear head were the same as the intake cam pulleyon the front head. So three the same and the one at the front of the car is different, anyone else noticed this, or is it unique to mine?.

[Davezj]

YES i post the same thing earlier, mine is exactly the same.

Just an aside how do you get the picture to be open in the post mine a just links but they do open to pictures.

Cheers Dave

[Kieran]

Yeah, that's same as my engine too - God knows why Mitsubishi chose that design though?

[Kenneth]

possibly that pully takes the majority of the torque from the cam belt, and is made more solid as a safety/reliability thing?

[The Vee]

Cam position sensor

[Kieran]

Cam position sensor

Aaaaaaah.... Of course!

[Louis]

So, do you reckon that the Cam position sensor would affect pulley design.

[wrdmotorsport]

I should be able to strip all the cam gears and pully's off my old engine next week if that will help. Exactly which ones do you need?
we can also send you a set if needed

[Wodjno]

Any chance they could be lightened a Tad :inquisiti

Or is there not much there to lighten :thinking:

And would it make much difference anyway :D

[chrisflorey]

Hi All .

I will gladly take any pulleys you guys can throw at me!


With cam gears I will have to check to se we have the right tooth cutter but ti should be ok,

The best way to get the most power out of cam gears is lighten them and make them adjustable!

Let us know what pulleys you have ...


cheers chris

info@cdfracing.co.uk

[Wodjno]

Hi All .

I will gladly take any pulleys you guys can throw at me!


With cam gears I will have to check to se we have the right tooth cutter but ti should be ok,

The best way to get the most power out of cam gears is lighten them and make them adjustable!

Let us know what pulleys you have ...


cheers chris

info@cdfracing.co.uk

Sorry all /pan

Didn't read all the post :speechles

Ignore my last 1, if you haven't already :scholar:

[bradc]

adjustable cam gears would be great :D

[zentac]

Chris,
I only had chance to get the cam gears off today so I will get those in the post to you tomorrow. The VR4 has 2 different cam gears (4 cam gears in total), 3 are identical and one has a cam timing bracket on the back. I will post you one of each.

As bradc said adjustable cam gear would be good.

[zentac]

They will be going in post this morning, should be with you Sat/Mon.

[Eurospec]

Lightened bottom pulleys- this is always a big debating point.

I will say first that i dont KNOW for a FACT, but i can tell you my experiances and those of others in the trade to some extent.

The issue is this:-

The standard bottom pulleys are heavy and have a rubber doughnut in them. They are balanced of course.

The reason they use a big heavy power sapping, lump of pig iron is that this is what damps out the harmonic vibrations of the crank shaft. Skyline, Supra, GTo, FTO, EVO, Galant, they all have a heavy bottom pulley. The more weight the pulley has, the greater its inertia (hence power sapping), and the greater its ability will be to abrorb (damp) the harmonic vibrations of the crankshaft. The heavier the pulley, the lower its natural harmonic frequency will be, and the more damping effect it will have on the vibrations of the crank as it moves away from that natural frequency.

Theory says if you lighten that pulley, although it is still balanced, it will have a higher natural frequency and less mass to damp out the vibration of the crank. So it could be 'claimed' that a lightened bottom pulley is bad because its own natural frequency is higher, and thus 'may' be in the running range of the engine, and when it moves away from its natural frequency its damping ability on the crank itself is less. It also follows that the vibrational load of the pulley itself even when vibrating at its natural frequency will be much less.

On balance, i believe that they are not an issue in themselves, but that lightened bottom pulley have less capability to damp the harmonic vibrations of the crankshaft simply because they have less mass. By the same token, because they have less mass, they offer less inertia, and so do boost engine performance.

So the question is what evidence do i have to support my theory?

In the last 7 years we have known of 1 car blow its bottom end after it had been fitted with one of these pulleys- not one from Chris i hasten to add. It was balanced. There is no proof that this car blew its bottom end because of the fitment of the pulley, or that the bottom end would not have failed anyway. The customer was very happy with the product and its performance in terms of bang for buck, however, after the pulley was on the car about a year, the bottom end failed. This customer used the performance of his car fully, and there is no conclusive proof one way or another- simply 1 bit of circumstantial evidence.

However, i do have something else. We fitted a lightened bottom pulley to an EVO. Immediately it was on it was obvious there was a problem. At 3000 rpm you could hear the vibration in the crank. You could hear a hum as you approached 3000 revs, at 3000 bang on it was so loud you could clearly hear it in the cabin above the stereo. We checked it was fitted correctly- which it was- and then advised the customer we wanted to remove it from his car, which he accepted and we did. Old pig iron pulley back on, no problems. This pulley came from e-bay.

Now i even ran an aftermarket bottom pulley on my own car for about 18 months- no issues. But when we built the engine thats in the car now, i took it off. Hopefully, if you arent bored with the worlds longest post, you are wondering why?

Well a good friend of mine who i would class as an expert engine builder, someone who i trust and respect for his undoubted skills, told me that of the many engines he has rebuilt after a failed bottom end, a high proportion of them had failed after the fitment of aftermarket pulleys. Having spent £20k in parts on my own engine, i wasnt going to chance it for the little bit of power i might get back.

Now, that said, these lightened pulleys have been used in the USA for many years, by many people including race teams, and they do not believe there are any issues with them. If you go and check on 3si.com, you will see this point debated over and over.

So, to conclude:-

In 7 years, we have seen one car with a failed bottom end, which occured around a year after fitment of a lightened pulley. We probably get delivered 5-7 cars a month with failed bottom ends. There are 2 in the workshop now, both completely standard.

I ran them myself on my normal engines.

We fitted one on an evo, out of many we have fitted which obviously produced vibrational issues.

We fit them for customers afer explaining the debate.

A good friend and trusted expert mechanic i know believes there is a correlation between lightened pulleys and bottom end engine failure

The theory says the capability of a lightened pulley to damp crank vibrations is less.

Of all those fitted by us, save for the two examples, we have never experianced any issues.

In the USA where these are in common use, though there is debate, many major tuners and engine builders do not believe there is an issue.

Bottom line, you pays your money and you takes your choice. My own belief is that because the pulley has less mass, it is less effective at damping crank vibrations. Because of that it 'may' have an impact on how long a bottom end lasts, but not on whether it will fail or not. My experiance suggests that this effect is small, considering the number of pulleys we have fitted and only one failure on an engine that had covered 70k miles, had been modified and was used hard and where the link between failure and pulley cannot be proven.

Chris, i dont mean to rain on your parade, i'm just saying my experiances. I think in general terms these products are fine, and i am sure yours is.

Cheers,

Ben.

[Eurospec]

Sorry, one other thing i should have said:-

Put this in context; when the cars were designed, so me guy designed a service life and a power output for the car.

He knew that at x power output, the service life is y.

Whatever you do, anything, even down to an air filter or an exhaust, if it changes the cars power output up, you are reducing its service life. Y is going to become smaller if you want.

I wonder if you could reaserch cars with aftermarket air filters vs std, because the filtration is less effective, if you would see an increase in bore wear because of an increase in particulate ingestion. I bet you can.

My point is, make your decision with as much knowledge as you can, and dont be thinking my bottom end might fall off if you are not thinking my bores might be getting scored more than normal.

Cheers,

Ben.

[Kieran]

Thanks for that information Ben - Very useful read. Have a rep point!

On a similar note.... What about these?

http://www.fluidampr.com/

[zentac]

Interesting read ben, I guess it all depends if you want a race engine that your going to strip at least yearly which probably does less than 5000 miles a year and put new bearings etc... in or if you want a daily runner that will last 100,000+ miles.

[zentac]

Thanks for that information Ben - Very useful read. Have a rep point!

On a similar note.... What about these?

http://www.fluidampr.com/



I love the quote on that page

"Hammers are not instalation tools!" since when (has anyone mentioned that to BDA)

[steve190]

Thanks for that information Ben - Very useful read. Have a rep point!

On a similar note.... What about these?

http://www.fluidampr.com/


We have something similar fitted to the gas engines I work on. They have a service life of 20000 hours and then have to be changed. They are also highly susceptible to damage. If it is dropped it cannot be used as the silicon deforms and then it is out of balance. And they are not light :pimp2:

[Kieran]

We have something similar fitted to the gas engines I work on. They have a service life of 20000 hours and then have to be changed. They are also highly susceptible to damage. If it is dropped it cannot be used as the silicon deforms and then it is out of balance. And they are not light :pimp2:

/Decides he's better off with a standard pulley then.....:inquisiti

[chrisflorey]

Ben : I have caught my breath now... Great write up! :2thumbsup

To be honest I couldn't of put it better myself , and when you meation about the Evo and the Ebay pulley all became clear! I have had some of those pulleys to look at and they are crap...I mean really bad!


Got the cam gear today cheers! They look ok to make, will have to check at the factory that we have the right cutter but we should have , also will need to look into make them adjustable,

What sort of quantities do you want me to quote on peeps?


chris

[zentac]

Ive start a new thread and get a list of interested parties.

http://www.clubvr4.com/forum/showthread.php?p=227746#post227746

[Wodjno]

I had the head gasket replaced when i got the water pump, tensioner, idoler, cam belt, cam shaft seals, etc, etc it cost me over a grand. but it could have been worse as you say. I got the car low loaded to the garage which i thougt was a must with the belt looking like that.

Cheers Dave

Feck Me Dave :speechles

I bet you were shocked and relieved when you saw those belts :inquisiti

Lucky, Lucky so, so Lucky :5shots:

[Funkstar]

Great write up again Ben. You make things easier for us newbies to understand. Keep on posting dude. Top work.

[zentac]

This guy got 8-10 bhp across the board on a normally aspirated 135bhp engine

http://www.nolimitmotorsport.com/aem/cam.html

[Eurospec]

Are they not talking about adjustable cam pulleys their Richard?

Its a good gain nontheless. You can get solid gains from lightened pulley sets (Bottom pulley, alternator PS pump etc), i've seen a chart for an RX8 that got 12bhp from a lightened bottom pulley, alternator pulley and PS pump pulley- although i think they may have been under drive pulleys to be fair.

With adjustable cam wheels you can get more out of what you have too. Increasing the overlap is a favourite for developing more torque, but this can also lead to low rpm reversion which isnt great. You do 'loose' some boost because a proportion of the intake charge goes right out of the exhaust, but you gain it back as you have a better 'fill' of the cylinder. Also you can always turn the boost up a bit more.

Cheers,

Ben.

[White Lightning]

Great write up again Ben. You make things easier for us newbies to understand. Keep on posting dude. Top work.

Agreed. Keep up the good work Ben :thumbsup:

[ralliart-type-s]

:thinking: So......if I keep the standard bottom pulley but uprate the rest to lighter adjustable ones, will it make much difference?? Will it keep my lump reliable??

[Davezj]

would be nice to have and i think they look great, i would have to run the engine without cam covers or get some transparent ones.now that would look good.
But they are too expensive for me at £262 for a set of 4 adjustable, hard anodised, and coloured. i probably wouldn't even notice the differance in performance.

Maybe if you had a modified car it might be the right step for you.

they would still look cool.

[zentac]

Are they not talking about adjustable cam pulleys their Richard?

Its a good gain nontheless. You can get solid gains from lightened pulley sets (Bottom pulley, alternator PS pump etc), i've seen a chart for an RX8 that got 12bhp from a lightened bottom pulley, alternator pulley and PS pump pulley- although i think they may have been under drive pulleys to be fair.

With adjustable cam wheels you can get more out of what you have too. Increasing the overlap is a favourite for developing more torque, but this can also lead to low rpm reversion which isnt great. You do 'loose' some boost because a proportion of the intake charge goes right out of the exhaust, but you gain it back as you have a better 'fill' of the cylinder. Also you can always turn the boost up a bit more.

Cheers,

Ben.

Yes they are ben, and thats what were getting made up first.

[Subaru ETA]

we were fitting underdrive pullys to v8 falcons at work....however since they help the engine spin up quicker and the oil pump is only operating at factory spec the engine did 15000km and seized! but this could also been coz it had the pullys and a lightened flywheel