Lightened Crank Pulley

[dougy]

3 minutes ago, S70-R said:

Well, for sure that if you search for it you'll find.

Do you believe that taking a single 1 gallon from your gas tank will make you any real faster?

That's the point...

uhmm ... welp you almost got me connived with that gallon point...but i'll just wait for you to find handful of failures. 

 

till then i'll just 

 

 

 

here i found this ...he has the car for 6-7 years

 

Finally got my lightweight crank pulley in, and took it down to Goodspeed today. I did a few runs on the dyno pre pulley install and layed down the
following:

287.1WHP
318.7 Torque

With the car still strapped down on the dyno, I had goodspeed swap the pulley and do two more runs:

The first run while the engine was cold, showed the following:

297.6 WHP
316.6 Torque

The second run immediately following showed:

296.2 WHP
323.4 Torque


The dyno chart pre and post is pretty awesome. In the lower RPM band, I gained a max of about 8hp and 10 torque. In the higher RPM band, I gained 9HP and 7 torque at peak, but the real gains are after 5k RPMS when my HP/Torque started to fall off, but after the pulley install, my HP was anywhere from 15-18HP higher, and my torque was 15-20 higher on the tail off.

Initial driving impressions are pretty awesome as well. I noticed that it helped with lag between gear shifts, and my overall powerband feels smoother. I would say, this mod is definitely worth 100 bucks.

 

 

 

 

[S70-R]

Very sarcastic as usual dougy.

I wonder when will you just discuss a matter here and simply accept a different view from yours without being sarcastic or conceited.

Just keep the light pulley and be happy with your 0,1% weight reduction and also your pocket reduction. I'll be happy with 0,1% more.

Anyway, my opinion was expressed and with no kind of rancor I just rest my case.

[dougy]

2 minutes ago, S70-R said:

Very sarcastic as usual dougy.

I wonder when will you just discuss a matter here and simply accept a different view from yours without being sarcastic or conceited.

Just keep the light pulley and be happy with your 0,1% weight reduction. I'll be happy with 0,1% more.

Anyway, my opinion was expressed and with no kind of rancor I just rest my case.

why get all sassy and mad ... it is a forum...but really ? NO articles to validate your  opinion? not even one with some pics? 

[S70-R]

Why don't you put things like this? -> The failure possibility is remote/low just as remote/low as the gains are.

Does 0,1% weight reduction worth my/our time to search for a single case/pic of an engine failure caused by aftermarket light pulleys?

Aftermarket pulleys failure you certainly have found. They are not a myth.

I'll just keep my car 0,1% fatter as well as my pocket :) you are of course free of continuing your route. I've no problems with that. And if you guys are happy with them that's fine.

I'm just not the guy that will drop a light pulley on my engine when the real total weight loss percentage is virtually 0.

[dougy]

oh - ok ... so nothing out there to prove/back your opinion. 

i mean you just spent some more time posting more of your opinions ...why not find something to back it ? i have 6 nice OEM stock crank pulleys in the attic...you really would be surprised  how easily i could be swayed to put them back on...seriously...im not being funny.   

[Kit Vexed]

oook now..  so according to your theory S70...  EVERYBODY ON HERE WHO HAS SWITCHED FROM DUAL MASS TO SINGLE MASS SHOULD BE HAVING PROBLEMS BY NOW RIGHT??  SEEING AS SINGLE MASS IS MUCH MUCH LIGHTER THAN DUAL MASS???

dude, i guarantee not a single person will report anything other than increased engine noise from the switch by virtue of weight reduction and no rubber isolation..  and numerous ppl have been running 850 single mass flywheels in all sort of applications on here FOR YEARS..

i feel like you want your theory to be fact for someone reason, when there's nothing but proof on here of otherwise??

 

so let's get the postings going on all the people who have switched to single mass (in essence, lightening their flywheels) who have blown engines or decreased reliability in doing so..  we can use this as proof for your 'theory' now..  good??

[S70-R]

I think you guys are insisting to get to a point that was not my main point initialy.

Actually you are the ones who are trying to convince me of something not the opposite.

Let's review my first posts about it so maybe you can get yourselves a better conclusion of my statements.

" The crank pulley, no matter how light it is, has nothing to do with gearing and thus nothing to do with RPM being higher or lower. It can however help the engine to rev easier." (I recognize it may help)

"personally I'm not a big fan of lightened crank pulleys or lightened flywheels without taking into account all the other inertia componentes of the engine, especially the crankshaft."

"So, a lightened pulley will represent only a very very small percentage of all this weight/mass. Even a lightened flywheel will represent a small percentage over the total inertia mass."

I prefer to stick with a stock and factory balanced set of crankshaft, pulley and flywheel once the potential gains are very small when the clutch is engaged and once messing up with the weights and balance of the engine can have nasty consequences." (I said it can. I didn't say it will which are different things)

"However, when the clutch is engaged, the easier acceleration would be much less noticable because the rotating mass increases a lot.

And because of that (little gains to be add), I prefer to not mess up with the engine balances. I'm not saying you will for sure f*** the engine. I'm just saying what I prefer given the small gains to be added."

"Once again, my point is: Given the really small (if any) gains I wouldn't bother with a light pulley."

Anyway. If you are looking for failing lightweight crank pulleys you can check one here (I know you are looking for internal engine damages caused by increased vibration or by some bad balance) - http://www.evoxforums.com/forums/showthread.php?t=50463

I was not talking about the flywheel in most of the posts. For my current build I will actually use a SMF instead of my stock DMF because I'll use the 707 plate. But I'm using the SMF not because I really see a crazy advantage on its lightweight but because is a need for the 707 and R disc.

Now it's your turn. Show us a performance comparison using a stock pulley vs a lightened one, let's say a dyno graph or a clocked pull.

That is the point. Show us the evidence of real performance gains in the real world by using the light pulley instead of the stock one. The flywheel may have a bit more of advantage cause it weights much more.

You could have post that on a new post dougy.

Doesn't make sense to EDIT a post of a few hours ago to add new relevant info.

Anyway, a 3% difference in hp/tq is something that you have already probably seen on the same dyno, on the same day, on the same tune, just different runs. I actually already did myself with mine...

Who knows if the stock pulley run was not already a hot run? He says the lightweight pulley was a cold run...

[dougy]

???? lolz

 

 I was out on my private strip doing a few tuning pulls and getting my new turbo kit dialed in. I had just finished up run # 20 something and started packing everything up after making 640whp and 490wtq (Power is probably a contributing factor here as well).

improper tuning man. 

billet aluminium crank pulley not falling apart. 

 

 

 

 

over  1000 pulls on it 

[dougy]

34 minutes ago, S70-R said:

 

Doesn't make sense to EDIT a post of a few hours ago to add new relevant info.

 

there is no EDIT...it combine my post as i posted minute before you and you missed it silly...

[S70-R]

1 minute ago, dougy said:

there is no EDIT...it combine my post as i posted minute before you and you missed it silly...

Ok silly dougy.

You say that a pulley failing is due to improper tuning?

High power may have contributed to that end. It's what the guy says. And that doesn't surprise me. Alumin vs steel...you know what will break first under hard vibrations/twists.

I post again what I said about the dyno graph because the 2 posts were automaticaly merged.

"Anyway, a 3% difference in hp/tq is something that you have already probably seen on the same dyno, on the same day, on the same tune, just different runs. I actually already did myself with mine...

Who knows if the stock pulley run was not already a hot run? He says the lightweight pulley was a cold run..."

A 3% difference is perfectly acceptable between different runs (because of engine temperature / charge temperatures).

So let's do an average of 1,5% between 0% and 3% and assume the pulley gave 1,5% more power (and less torque in the low revs). Those are the small gains I was talking about. I think you just proved what was my main point.

If you guys are happy with that, that is totally fine. It is just something that I will not bother with at the moment. Probably in a maxed out situation, like maxed turbo, maxed intake, etc etc etc, a light pulley and/or light flywheel may become a priority as a last resort to extract slight more power.

[dougy]

.where is premature main bearing failure? lol... his bottom is perfect...which only proves no internal damage whatsoever and he had light weight pulley...most likely a cheap one... don't get me wrong , i would love to see some real evidence of failure on the net...that's not very good one. I was hopping to find many myself but no success..

[Kit Vexed]

oh god..  back-peddling denotes your lack of willingness to accept defeat..  dude, you're wrong.  it's totally ok.

not sure what your logic is in saying a lightened flywheel doesn't effect the overall rotational inertia as much as a crank pulley??

 

ask someone if they noticed more of a difference in lightening their flywheel, or bolting up a pulley...  i promise you they wont say the lightened pulley made more of a difference than a flywheel lol

 

im getting dumber by having to explain this to you though, so im out.  i'll let dougy just keep finding evidence to back up his notion while you just squabble trying to be right with no evidence  =)

[S70-R]

Defeat, wrong? Really? Is this kind of a battle for you? I wonder if this thread is still a thread or some kind of nursery...

If you read my posts AGAIN I have nothing to accept or admit. Since the beginning I said the ligher crank pulley could help to rev easier and could yield little gains.

dougy dyno post just proves the point, those are marginal gains.

And apart from that what I just have said is that I'm not the biggest fan of changing balancing components (especially as a primary source of power) because in the long run that may have some impact. And for sure additional bearing wear or bearing failure will not be seen in the first thousand miles. If it happens it will likely be in the long run and unless you tear apart your engine, or you have a failure, you'll not be aware of potential additional bearing wear.

As a last resort I would consider a lighter pulley. As a primary source of power I rather do other mods. Is it so hard for you to understand my logic?

And I have the right to establish my priorities to my builds, don't you think? Or that does mean I'm not willing to accept your god's view?

"not sure what your logic is in saying a lightened flywheel doesn't effect the overall rotational inertia as much as a crank pulley??"

Where did I say this??!! I have just said the opposite! A flywheel effect the overall rotational inertia considerably more than the crank pulley.

The whole thread was about the crank pulley and you keep talking about flywheels? Do I need to repost what I talked about flywheels here??? Gosh...

"The flywheel (lightened one over a crank pulley) may have a bit more of advantage (over using just a lightened pulle) cause it weights much more." This is what I said!

You better get some glasses, sorry...

[Kit Vexed]

"So, a lightened pulley will represent only a very very small percentage of all this weight/mass. Even a lightened flywheel will represent a small percentage over the total inertia mass."

I prefer to stick with a stock and factory balanced set of crankshaft, pulley and flywheel once the potential gains are very small when the clutch is engaged and once messing up with the weights and balance of the engine can have nasty consequences." (I said it can. I didn't say it will which are different things)

"However, when the clutch is engaged, the easier acceleration would be much less noticable because the rotating mass increases a lot.

And because of that (little gains to be add), I prefer to not mess up with the engine balances. I'm not saying you will for sure f*** the engine. I'm just saying what I prefer given the small gains to be added."

"Once again, my point is: Given the really small (if any) gains I wouldn't bother with a light pulley."

 

ummmmm.. ???  you're saying the gains are little to be had and "EVEN A LIGHTENED FLYWHEEL WILL REPRESENT A SMALL PERCENTAGE OVER THE TOTAL INERTIA MASS"

 

but now you're following up this quote with the above, " Where did I say this??!! I have just said the opposite! A flywheel effect the overall rotational inertia considerably more than the crank pulley"

 

YOU JUST SAID IT.   dude you're wack or off your meds lol..  is this how you are in real life??  you literally say something, then when someone calls you out you say you never said it??  unfortunately for you, you've posted  your hypocrisy and can't hide it lol..

 

i 

[NEU]

s70R, most mods are "marginal" gains, (i.e. NA cams, turbo intake pipe, open filter, spark plug cables, intercooler, RIP, etc. etc. etc... see what I'm doing?). But when you put several of them together you get a "substantial" gain. You could replace lighten crank pulley with anything in your list of mods and say "alone it's not worth it".

Your opinion whether the lighten pulley is worth it or is going to destroy your engine, especially without proof and backpedaling, isn't helping you convince anyone... Find some proof, stand your ground and you might have valid debate, but without it you're just spouting your opinion, parroting internet myths and swaying in the breeze.