Another underdrive/harmonic balancer pulley question
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Thanks. Browsing through sponsor sites, I came across a member by the name of 99blancoss who sold the ati 10% underdriven balancers for like 390 shipped. I went to his site and I don't see them at that price, so with that being said; which sponsor sells for the best price? Thanks!
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Well, based off what you fellas said, I don't plan on going over 500 horsepower... So from what I understand, this will be more beneficial for my power goals. It was 419 bucks shipped. Ordered a grand worth of **** there as well.
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Last edited by UnVMySS; 10-23-2013 at 06:56 PM.
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Pity I didn't see this thread earlier....sometimes on E-Bay you can come across the ATI pulley you want at a way cheaper price, ATI sell off the blemished pulleys 'paint mark' at around 1/2 price.
Got mine that way
Got mine that way
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soundengineer, even though i dont see any proof im not going to dispute you if you say ATI is the best (nhra approved). what i will disagree with is implying its ATI or nothing. arent most if not all of these aftermarket pulleys sfi approved? doesnt that make them an upgrade over stock? do you have proof on rwhp gain from ATI over SLP or powerbond etc? im just the average backyard john doe hot rodder , why should i spend the extra $200 / $250 on an ATI? can you guarantee me my ls1 will last longer? top of the line parts arent for everybody. how much total have you spent on your hobby? how much could you sell it for? financially whats the best choice? thx just my one cent.
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soundengineer, even though i dont see any proof im not going to dispute you if you say ATI is the best (nhra approved). what i will disagree with is implying its ATI or nothing. arent most if not all of these aftermarket pulleys sfi approved? doesnt that make them an upgrade over stock? do you have proof on rwhp gain from ATI over SLP or powerbond etc? im just the average backyard john doe hot rodder , why should i spend the extra $200 / $250 on an ATI? can you guarantee me my ls1 will last longer? top of the line parts arent for everybody. how much total have you spent on your hobby? how much could you sell it for? financially whats the best choice? thx just my one cent.
started with a stock pulley on a cammed motor.....went to an SLP and gained a couple of HP from the pulley change..
Later when I switched to my 408 I reused the SLP Underdrive Pulley.... when we went to the dyno my engine was falling off unusually early for the size of cam I have...
at the time it was a 248/252 on a 108 ICL...it was done by 6100 rpm and falling off quickly...quicker than expected by the cam builder and by myself.
from tuning hundreds and hundreds of cars I knew it should be more like 7000-7200 with that cam
we looked at everything...springs, valves, pushrods, lifters.....nothing made a difference...
I was stumped...but an engineer buddy of mine thought it may be harmonic vibration related.....being caused by the damper....or not being controlled by the damper
after a thorough discussion and talking to him about his racing experiences...I thought it was worth a shot and worth the piece of mind anyways since I was going to make more power with a power adder and I wanted to prepare for a dry sump or a vacuum pump anyways...
I bought a Full size ATI pulley/Hub combo with a Gilmer(HTD) belt drive on it to prepare for the vacuum pump
across the entire RPM Range(starting about 3000 rpm) I picked up 5-10 HP..... and my RPM carried out to 7400 rpm as expected...
all that issue(on my setup) was caused by an SLP underdrive pulley
so I gained power over the SLP Underdrive pulley by switching to the ATI, and I gained stability that allowed me to hold my power out to higher rpms.