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Old 02-01-2011, 01:57 AM   #1
keylay
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Default Any one with a 2.5i with light weight crank pulley

Anyone have experience with a light weight crank pulley on a 2.5i (mine is a 2011) with a 4EAT? I'm guessing it won't add much power, but have heard it's a little easier to rev. School me
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Old 02-01-2011, 02:18 AM   #2
blckout7
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Not worth trust me, I've gone through this myself. 1) bitch to install on 4eat 2) we don't have a 5 speed so the drivetain loss that we experience won't even let us feel that $150 investment. 3) although there are harmonic dampeners (i could be wrong) we still have a chance of getting vibrations which are very bad =( sorry brother
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Old 02-01-2011, 02:29 AM   #3
keylay
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Quote:
Originally Posted by blckout7 View Post
Not worth trust me, I've gone through this myself. 1) bitch to install on 4eat 2) we don't have a 5 speed so the drivetain loss that we experience won't even let us feel that $150 investment. 3) although there are harmonic dampeners (i could be wrong) we still have a chance of getting vibrations which are very bad =( sorry brother
So you did this on yours or that's the concensus of others? If that's the case, I'll save for some wheels/tires. If any others have installed, looking to hear what you thought too.
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Old 02-01-2011, 03:27 AM   #4
williaty
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for a 4EAT, it's not worth it. The 4EAT doesn't try to change engine speed rapidly enough to benefit from the reduction in rotational inertia.
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Old 02-01-2011, 07:37 AM   #5
NH8991
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My 2 cents, for what it's worth

I have a Group A crank pulley on my 2.5i 4EAT, cost me $100, was easy to install (used a strap wrench to get the original pulley off, no problems).

Performance improvement? On acceleration, maybe it revs a little more readily,maybe that's just wishful thinking.
But the big difference is decelaration, the car behaves more like a manual, it actually engine brakes now, i don't have to worry about lifting off and continuing on to rear end the car in front, and i can increase the amount of engine braking by downshifting using the 'Sports Shift'.

For me, worth every penny for an easy mod.

Cheers.

Last edited by NH8991; 02-01-2011 at 09:12 AM. Reason: Bad english, and i'm English!
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Old 02-01-2011, 09:08 AM   #6
Wrencher86
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Quote:
Originally Posted by williaty View Post
for a 4EAT, it's not worth it. The 4EAT doesn't try to change engine speed rapidly enough to benefit from the reduction in rotational inertia.

And for a 5spd?
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Old 02-01-2011, 09:48 AM   #7
Boxer4Dad
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Quote:
Originally Posted by Wrencher86 View Post
And for a 5spd?
It makes it noticeably easier to rev-match when downshifting. I also think it helped me keep from bogging down exiting tight turns during autocrosses, but that was kind of into the gray area of my butt dyno's accuracy, so maybe, maybe not. I like mine a lot.
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Old 02-01-2011, 10:17 AM   #8
renyo
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Quote:
Originally Posted by NH8991 View Post
My 2 cents, for what it's worth

I have a Group A crank pulley on my 2.5i 4EAT, cost me $100, was easy to install (used a strap wrench to get the original pulley off, no problems).

Performance improvement? On acceleration, maybe it revs a little more readily,maybe that's just wishful thinking.
But the big difference is decelaration, the car behaves more like a manual, it actually engine brakes now, i don't have to worry about lifting off and continuing on to rear end the car in front, and i can increase the amount of engine braking by downshifting using the 'Sports Shift'.

For me, worth every penny for an easy mod.

Cheers.
Eh, this.


I got a pretty good deal for mine (like 70 bucks) on eBay if I remember correctly. Installation was as easy as doing the drive belts. I just jammed a screw driver in the inspection hole at the back of the engine and everything came off fine. Although admittedly, the inspection cover was a pain in the ass to get back on. I also did this for the most part after the sun set.

Again, it maybe looks like it accelerates a little faster (based on the tachometer). I didn't notice a change in engine braking at least... I'll try downshifting a couple times to see if I notice anything different though.

Edit: Engine braking might be affected about as much as accelerating...

Last edited by renyo; 02-01-2011 at 02:22 PM.
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Old 02-01-2011, 02:16 PM   #9
lionsault
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From what I read and heard. Its not going to add much power at all. Like people said on here, it will rev a little bit faster but you wont notice it.
The install is easy on the new cars, the pulley is exposed and it wont take long at all to change it. Just make sure your belt is the right tightness. And that is my ext mod, depends on when I get custom headers done to the car.
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Old 02-01-2011, 03:16 PM   #10
williaty
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Quote:
Originally Posted by Wrencher86 View Post
And for a 5spd?
As the next poster said, for a 5MT, it'll noticeably make downshifts faster.
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Old 02-04-2011, 02:42 PM   #11
Henry H
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I actually like my lightweight pulley but not for the obvious/supposed reason. I might be wrongfully blaming my stock pulley but here goes.

Prior to the swap, I remember that I would feel a shock on the tranny when my car would accelerate after a slow-down. Let me illustrate an actual common scenario. Id be slowing down coming into a turn in my neighborhood. The tranny would drop to 2nd, then, as I accelerate by hitting the gas again it would feel like a punch to the engine, almost feels like letting in the clutch in too fast. And yes mine is a 4eat not manual. And to be clear, this is just normal conservative driving.

This happened all the time. After I installed the pulley, the problem was gone. Acceleration is unnoticeably better :-P , engine braking is definitely better, re-acceleration shock was gone. I only kept the pulley because of the latter reason.

Wish I could determine whether or not the lack of the harmonic dampeners are causing detriment but I feel nothing of the sort while driving. However, I suspect something like that is not detectable from inside the cabin.
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Old 02-04-2011, 05:30 PM   #12
kero
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^^ I get the same exact thing on my 07 2.5i wagon all the time with 4eat, I always wondered what it was and it's pretty strong sometime, sometimes a little less harsh. It kinda annoys me but does not happen all the time, only under certain conditions, which I cannot elaborate on cause when it happens, I'm not planning for it and don't remember what I did to cause it.
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Old 12-03-2012, 01:14 PM   #13
suuichi
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How long have you had this installed and how many miles I might want to do it for my 08 2.5i 4eat
Quote:
Originally Posted by Henry H View Post
I actually like my lightweight pulley but not for the obvious/supposed reason. I might be wrongfully blaming my stock pulley but here goes.

Prior to the swap, I remember that I would feel a shock on the tranny when my car would accelerate after a slow-down. Let me illustrate an actual common scenario. Id be slowing down coming into a turn in my neighborhood. The tranny would drop to 2nd, then, as I accelerate by hitting the gas again it would feel like a punch to the engine, almost feels like letting in the clutch in too fast. And yes mine is a 4eat not manual. And to be clear, this is just normal conservative driving.

This happened all the time. After I installed the pulley, the problem was gone. Acceleration is unnoticeably better :-P , engine braking is definitely better, re-acceleration shock was gone. I only kept the pulley because of the latter reason.

Wish I could determine whether or not the lack of the harmonic dampeners are causing detriment but I feel nothing of the sort while driving. However, I suspect something like that is not detectable from inside the cabin.
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Old 12-03-2012, 02:47 PM   #14
travisamorgan
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which lightweight pullies would you recommend? Grimmspeed? or another?
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