lightweight pulley and flywheel
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From: Palo Alto, Ca
Car Info: 13 Taco Double Cab 4x4/ 71 Datsun 510
You really should not use a light weight crank pulley because Subaru designed the pulley with a dampener to take up vibrations generated by the motor and if there is no dampener the vibrations could damage the thrust bearing and crank.
I thought you'd stopped making ridiculous statements after Tom at Kartboy called you out about your last claim that kartboy shifters break trannies
How many crank failures caused by lightweight pulleys have you personally seen? Before you answer bear in mind that the people at Cobb sell a lot of pulleys. I wonder what they would think of this statement?
Registered User
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From: Palo Alto, Ca
Car Info: 13 Taco Double Cab 4x4/ 71 Datsun 510
So you are saying that a lightweight pulley will damage the thrust bearing and crank??????
I thought you'd stopped making ridiculous statements after Tom at Kartboy called you out about your last claim that kartboy shifters break trannies
How many crank failures caused by lightweight pulleys have you personally seen? Before you answer bear in mind that the people at Cobb sell a lot of pulleys. I wonder what they would think of this statement?
I thought you'd stopped making ridiculous statements after Tom at Kartboy called you out about your last claim that kartboy shifters break trannies
How many crank failures caused by lightweight pulleys have you personally seen? Before you answer bear in mind that the people at Cobb sell a lot of pulleys. I wonder what they would think of this statement?
Last edited by Ballz; Aug 17, 2009 at 07:55 PM.
There's definitely some truth to what Ballz said, because the boxer engine isn't inherently balanced. Subaru wouldn't have a damper on the pulley for nothing.
I am not, however, sold that vibration is a big issue that destroys main bearings. My previous engine had an unorthodox underdrive pulley for 98K and the bearings were fine. It also was tracked many many times, had a JC sports turbo kit, and wasn't babied at all (had receipt for new transmission). Blown turbo seals, my lead foot, and detonation killed in finally.
Until someone sets up a bench test for this theory, I'm fine with running my lightweight and underdriven pulley with a lightweight flywheel.
I am not, however, sold that vibration is a big issue that destroys main bearings. My previous engine had an unorthodox underdrive pulley for 98K and the bearings were fine. It also was tracked many many times, had a JC sports turbo kit, and wasn't babied at all (had receipt for new transmission). Blown turbo seals, my lead foot, and detonation killed in finally.
Until someone sets up a bench test for this theory, I'm fine with running my lightweight and underdriven pulley with a lightweight flywheel.
Glad to hear some that are running both. I ordered Kartboy's pulley since it's lighter than stock but more than most.
What flywheel are you running? I'm thinking ACT streetlight since it is the heaviest of the lightweight flywheels.
What flywheel are you running? I'm thinking ACT streetlight since it is the heaviest of the lightweight flywheels.
Registered User
iTrader: (44)
Joined: Aug 2006
Posts: 6,133
From: Palo Alto, Ca
Car Info: 13 Taco Double Cab 4x4/ 71 Datsun 510
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From: Man Jose
Car Info: 02 WRB WRX Wagon, 08 SSM STI
Subarus do not come with a harmonic damper or balancer like some other vehicles do. For other manufacturers' vehicles, this is a legitimate concern. Proof:
"Thank you for your patience as I checked with our Technical Services Department regarding your message below. They advised that the crank pulley is a pulley and nothing else. It is not used as a harmonic damper/balancer.
Thanks for the opportunity to be of assistance. If you need any future assistance, please feel free to contact us again."
Best wishes,
John J. Mergen
Customer Service Department
Subaru of America, Inc.
"Thank you for your patience as I checked with our Technical Services Department regarding your message below. They advised that the crank pulley is a pulley and nothing else. It is not used as a harmonic damper/balancer.
Thanks for the opportunity to be of assistance. If you need any future assistance, please feel free to contact us again."
Best wishes,
John J. Mergen
Customer Service Department
Subaru of America, Inc.
I run the streetlight. It's only 4 lbs lighter than the stock flywheel IIRC. No issues so far.
