Help with new harmonic balancer.
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Racer
Joined: Apr 2019
Posts: 359
Likes: 124
From: South Louisiana
Help with new harmonic balancer.
I need to change the HB. Undecided wether to go stock size or underdrive. Thinking of going 25% under. I have a 2001 z06. Being a manual helps. And I don't do a lot of city driving. Mostly highway and backroad cruising.
Last edited by Daveinnola; May 2, 2020 at 11:47 PM.
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From: South Hill Wa
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The only time I would ever consider an underdrive crank pulley would be dedicated drag racing. All other times there is not enough gain to justify the losses.
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Drop an underdrive on it and call it a day. Plenty of guys with years running underdrive pullies with no negative effects.
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Joined: Aug 2018
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From: South Hill Wa
2022 C5 of the Year Finalist - Modified
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Didn't mean to imply that they don't work or cause massive problems. I know that's not the case
I myself don't see the point in running one for such little gains. I'd rather find 3-5hp somewhere else.
I myself don't see the point in running one for such little gains. I'd rather find 3-5hp somewhere else.
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From: Insert Wittty Comment here
I just went the opposite way. One of my cars had an underdrive pulley on it that came apart (old ASP unit). I ended up putting an ATI back on with the stock size. That being said, I never really saw any issue with the underdrive unit in terms of accessories.
Thread Starter
Racer
Joined: Apr 2019
Posts: 359
Likes: 124
From: South Louisiana
Just a follow up. I finally got around to finish the work on my car. I went with the Summit racing 25% underdrive pulley. I also put on a set of speed engineering headers and new Magnaflow exhaust. Finally got it finished and tuned with HP tuners. All I can say is WOW. Like having a new car. Sitting at a red light idle is 750 rpm. No problems with A/C or alternator. I can idle just fine. The engine is definitely more snappy. Also replaced plugs and wires while I was under hood and other general maintenance. I'm at 64 k right now. Good for many more miles.