Underdrive crank pulley and lightweight flywheel

JDM 1JZ

I hate Tires
Aug 31, 2005
301
0
0
39
Cherry Hill, New Jersey
Hey guys, after being dormant for about 6 years I am in the process of doing a aristo 2JZGTE swap into my 89 MK3. So far my list of parts needed is very slim now and I will be assembling the drivetrain after I receive my harness back from tweakd and a few missing parts from driftmotion.

I did order a complete underdrive pulley set from Driftmotion. I needed a water pump pulley for the jdm to usdm waterpump conversion and figured why not fork out the extra money for the complete set. After hours and hours of reading and technical articles I see many saying it's either OEM, ATI, BL, or FLUIDAMPR for the principles of harmonics of the crank shaft. I see many including Aaron and DM who claim they have ran them for years and years without issue.

I guess my question here is, why is there such a worry over an unharmonic balanced crank pulley and not so much over a light weight flywheel. Wouldn't it basically run under the same principle everyone is against or talking about? I'll get my flame suit ready incase this is a stupid question because I get it but I don't get it. I've ready probably everything thread from here all the way back to mkiv.com
 

hvyman

Dang Dude! No Way Man.
Staff member
Apr 17, 2007
12,568
1
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Fullerton,CA
flywheels are still heavy and the clutch and pressure plate bolts to them as well.

A light weight crank pulley weighs almost nothing and has no dampening.

using a light weight crank pulley to gain 1hp is not worth the potential damage to the engine. Its not like your going to gain 50 hp. If you want more power run more boost.