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something new i want...

jeff

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#3
I wondered when pulleys would happen for our cars...

I loved them on my Acura...

But a bit unsure if needed the fiesta already revs so quick and melts tires.
 


Dpro

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#5
A lightweight pulley might give more hp but you'll lose torque.
This is true, its a trade off. On say a BMW inline six that generate gobs of torque it can be really cool and not reduce the torque enough to matter. With our engines? Granted our engines are long stroke engines which on a 4 cylinder can really be the key to Torque, but at the expense of higher revs.
It depends on how much Ford relied on weight of the pulleys and flywheel to add in more torque.
 


jeff

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#6
Another question is the belt. With the pulley being larger diameter, will the OEM belt still work and if so for how long seeing it is being compromised? When I did pulleys on my TSX back in the day I had to change the belt size.
 


jeffreylyon

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#7
A lightweight pulley might give more hp but you'll lose torque.
You won't lose torque, you'll lose inertia. This makes getting off the line more difficult, as does a lighter flywheel, but less engine torque will be used in spinning up the engine, resulting in more torque delivered to the wheels. Further, turning the accessories more slowly means more torque available at the wheels.

HP is just (torque * revs). At any given engine speed more of one means more of the other.
 


green_henry

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#8
Another question is the belt. With the pulley being larger diameter, will the OEM belt still work and if so for how long seeing it is being compromised? When I did pulleys on my TSX back in the day I had to change the belt size.
I had a TSX with a lightweight crank pulley from Unorthodox Racing, and it shipped with a slightly smaller belt. Interesting that Pumaspeed makes no mention of the belt.
 


jeff

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#9
I had a TSX with a lightweight crank pulley from Unorthodox Racing, and it shipped with a slightly smaller belt. Interesting that Pumaspeed makes no mention of the belt.
That pulley made a very nice difference on my Acura.

I emailed Pumaspeed earlier today, we'll see how they respond. I am wondering about the belt and also about the drain on the other accessories. The A/C in our cars isn't exactly world-class as it is, to compromise it by adding this pulley may not be what I want to do to my car. But it's so cheap I'm tempted to just order one and take one for the team.....
 


jeff

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#10
I went ahead and ordered one of these. I'll post a review and thoughts once installed.

After talking with the folks at Pumaspeed I have a bit more info; this is copy paste from email correspondence:

*****
Hello again.

I see this new lightweight pulley product and am interested in it for my US spec 2015 fiesta ST. Will it fit and are there any reviews of it yet? I am concerned about the effect on the other belt driven components of the car, I do not see any information or reviews.

Thank you.

*

It is brand new so only a handful of people have fitted one, initial feedback seems positive and it should fit a US spec car absolutely fine.

Regards

Lewis O’Neill

Pumaspeed

*

Does it work with the belt or is another belt needed? Being that it is a larger diameter I am concerned about this.

Thank you.

*

Of the 10 or so we’ve sold the majority of people have managed to fit with the stock belt although it’s tight, one customer has chosen to get the next belt size up and said it fits much easier with this.

Regards

Lewis O’Neill

Pumaspeed

*

Thank you.

Would you happen to have that belt part number/size? It would be nice to have one on hand in case I choose to use it, and it would be very helpful if Pumaspeed could provide this so that this experience might be a "one stop shop" instead of having the car apart and having to run to the store and hope they have the correct belt in stock.

It is appreciated.

*

The customer who put the larger belt on used a 1583mm belt rather than a 1555mm belt

Regards

Lewis O’Neill

*****
 


danbfree

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#11
A lightweight pulley might give more hp but you'll lose torque.
This is true, its a trade off. On say a BMW inline six that generate gobs of torque it can be really cool and not reduce the torque enough to matter. With our engines? Granted our engines are long stroke engines which on a 4 cylinder can really be the key to Torque, but at the expense of higher revs.
It depends on how much Ford relied on weight of the pulleys and flywheel to add in more torque.
We already have so much torque that 1st and 2nd gears are almost unusable with just a tune.... and sure the engine doesn't go to 8000 RPM, but very safely can do 7200 like many other 4 cylinders, it's just the stock turbo keeping it from being worth it so Ford caps it low anyway... so as long as the AC works fine this really seems like a good idea, I just don't know if a different tune would be needed or preferred, maybe I'm over-thinking it... But seriously, I'd love to trade off 10 ft/lbs of torque for 10 HP up high instead, this seems like the PERFECT mod to help restore a little power balance with a stock donkey kick turbo.
 


danbfree

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#12
The customer who put the larger belt on used a 1583mm belt rather than a 1555mm belt
*****
Huh, let us know where you find to order one that size, which comes out to roughly 62 1/3 inch... And of course, looking forward to your comparison!
 


M-Sport fan

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#13
I never looked, but do our engines have a damped crank pulley/harmonic balancer from the factory?

If so, wouldn't we want a replacement to also be damped, maybe even better than the factory one (a la all of the ones offered for the LSx engine platforms, like the Fluidampr I had on my Z28), to kill the 'crank harmonics'?

Even if the factory one is not damped, would we benefit at all in (main bearing, crank/rod journals/wrist pins/etc.) reliability/longevity with a damped performance oriented crank pulley (like an ATI), especially when using raised rev limits, or is our engine just so perfectly balanced right from the factory, despite the 'stroker' geometry, that NONE of this even matters?
 


ron@whoosh

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#14
Huh, let us know where you find to order one that size, which comes out to roughly 62 1/3 inch... And of course, looking forward to your comparison!
from the Peron Aux fuel system install
"The alternator has to move fwd a bit and found out that the stock belt really puts extra tension on the tensioner pulley after the installation of the spacer. To fix this, I went with a one size larger belt, GATES K060615. Amazon sells the belt for $15.95"

This new pulley is an overdriven water pump pulley which increases the speed of the water pump
 


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danbfree

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#15
from the Peron Aux fuel system install
"The alternator has to move fwd a bit and found out that the stock belt really puts extra tension on the tensioner pulley after the installation of the spacer. To fix this, I went with a one size larger belt, GATES K060615. Amazon sells the belt for $15.95"

This new pulley is an overdriven water pump pulley which slows the water pump down
Nice find, thanks Ron!
 


green_henry

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#16
I never looked, but do our engines have a damped crank pulley/harmonic balancer from the factory?

If so, wouldn't we want a replacement to also be damped, maybe even better than the factory one (a la all of the ones offered for the LSx engine platforms, like the Fluidampr I had on my Z28), to kill the 'crank harmonics'?

Even if the factory one is not damped, would we benefit at all in (main bearing, crank/rod journals/wrist pins/etc.) reliability/longevity with a damped performance oriented crank pulley (like an ATI), especially when using raised rev limits, or is our engine just so perfectly balanced right from the factory, despite the 'stroker' geometry, that NONE of this even matters?
FWIW, I ran the UR lightweight crank pulley on my TSX for ~100k over 6+ years and it was still running strong and smooth when I sold it (and, yes, the original pulley was dampened).
 


jeff

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#17
FWIW, I ran the UR lightweight crank pulley on my TSX for ~100k over 6+ years and it was still running strong and smooth when I sold it (and, yes, the original pulley was dampened).
Same here I remember all the talk from people worried about harmonic balancing....it was all worry for nothing the car was fine.

On another note I would not be surprised if this pulley is the first of several they release for our cars.
 


TyphoonFiST

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#18
from the Peron Aux fuel system install
"The alternator has to move fwd a bit and found out that the stock belt really puts extra tension on the tensioner pulley after the installation of the spacer. To fix this, I went with a one size larger belt, GATES K060615. Amazon sells the belt for $15.95"

This new pulley is an overdriven water pump pulley which increases the speed of the water pump
If its gonna be over driven type why would you wanna slow down the water pump pulley with the overheating issues some of you already have? [facepalm]
 


Sekred

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#19
Its a larger diameter pulley so the WP is driven slower not faster. Driving it faster verse crank speed would increase load
 


Hijinx

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#20
You won't lose torque, you'll lose inertia. This makes getting off the line more difficult, as does a lighter flywheel, but less engine torque will be used in spinning up the engine, resulting in more torque delivered to the wheels. Further, turning the accessories more slowly means more torque available at the wheels.

HP is just (torque * revs). At any given engine speed more of one means more of the other.
Forgive my interjection, but the horsepower formula is (RPM * Torque)/5252. Alternatively, and close to your quote, RPM * Torque = 5252x; solve for x. What you suggest is that (RPM * Torque) = (HP * RPM).
 




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