[Z06] Underdrive pulley's?
Thread Starter
Instructor
Joined: Dec 2004
Posts: 159
Likes: 0
From: Omaha Nebraska
Underdrive pulley's?
Ok, not going crazy with my car. Just doing some normal bolt on stuff.
This is what I plan on doing....
Long tubes w/o cats
Vararam intake
Catback, Prolley B&B Bullets
I'm going to do a cam later down the line.....
So, for a 01' Z06, which is the best underdrive pulley to gain the most performance?
Thanks,
Steve
This is what I plan on doing....
Long tubes w/o cats
Vararam intake
Catback, Prolley B&B Bullets
I'm going to do a cam later down the line.....
So, for a 01' Z06, which is the best underdrive pulley to gain the most performance?
Thanks,
Steve
Melting Slicks
Joined: Jul 2007
Posts: 2,087
Likes: 11
From: Austin TX
The most popular are the Powerbond or ASP pulley. Both will yield similar hp, the PB could be found for $190, the ASP for about $240-260. With the ASP, you will also need a shorter a/c belt because it underdrives the a/c by 10%, the PB does not
Team Owner
Joined: Aug 2006
Posts: 30,897
Likes: 45
From: Picking on the weakest kid in the yard.
I just did this job because my stock pulley was wobbling a bit and would trow the belt at the track. It really is a huge job. So much so I was contemplating doing a cam since I was already in there so deep even though I don't even really want a cam right now. Definitely wait and do the cam at hte same time. On the positive side, I still have 14 volts when idling with the headlights, wipers, heater, and radio on with my powerbond 25% underdrive pulley. So I haven't seen any downsides to the pulley what so ever, yet.
Team Owner
Joined: Jan 2007
Posts: 31,233
Likes: 201
From: Utah
I just did this job because my stock pulley was wobbling a bit and would trow the belt at the track. It really is a huge job. So much so I was contemplating doing a cam since I was already in there so deep even though I don't even really want a cam right now. Definitely wait and do the cam at hte same time. On the positive side, I still have 14 volts when idling with the headlights, wipers, heater, and radio on with my powerbond 25% underdrive pulley. So I haven't seen any downsides to the pulley what so ever, yet.
Melting Slicks
Joined: May 2005
Posts: 2,209
Likes: 12
From: Montgomery Alabama
Cruise-In VII Veteran
St. Jude Donor '06
I understand it is best to move the steering rack out of the way. I also have the PS cooler to move.
What else did you have to remove to get to the pulley?
What else did you have to remove to get to the pulley?
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Team Owner
Joined: Aug 2006
Posts: 30,897
Likes: 45
From: Picking on the weakest kid in the yard.
It's not just best, it's required. With the puller I used, I had to completely remove the rack from the car, which required loosening and dropping the entire engine cradle down a bit. I probably could have gotten it out by removing the tie rod ends, but I didn't want to mess with the alignment. That means getting to the PITA power steering line to rack connections as well. It's not fun. But other that removing the rack, the only other part I remember removing was the intake bridge. You also have to be very careful to not turn the steering wheel while it's disconnected from the rack and to reconnect the steering shaft with the rack in the same position as well. Otherwise the active handling gets messed up. Basically, I wouldn't recommend doing this unless it's in conjunction with a cam swap or because you have to, like I did.
Melting Slicks
Joined: May 2005
Posts: 2,209
Likes: 12
From: Montgomery Alabama
Cruise-In VII Veteran
St. Jude Donor '06
Not to sound too dumb, but is there a timing mark on the pulley or the balancer?
Team Owner
Joined: Aug 2006
Posts: 30,897
Likes: 45
From: Picking on the weakest kid in the yard.
Thanks, I think I have to do it, though. When I went in there to swap out the thermostat, the belt was off one cog. The crank pulley wobbles some, and I don't want it coming off while I am on the road somewhere.
Not to sound too dumb, but is there a timing mark on the pulley or the balancer?
Not to sound too dumb, but is there a timing mark on the pulley or the balancer?
Burning Brakes
Joined: Feb 2009
Posts: 862
Likes: 1
From: DFW TX
That's exactly why I had to do mine. My crank pulley was wobbling which caused my belt to jump a rib and shred while at the track. First off, the crank pulley and balancer are not two peices. It's just a pulley, press fit onto the crank snout. It serves no balancing function so it can go on in any clocking and it has no timing marks at all. The new SLP/Powerbond underdrive pulley I installed did have timing marks on it to use if you want. But in order to make them correct, you would have to acurately find TDC, then clock the pulley to match. And why bother? All timing is done through the ECM anyway. I didn't bother to line up the timing marks on mine. I must say I am happy with it. It spins perfectly true and I have seen absolutely no change volts or felt any change in steering feel. So it fixed my problem without any side effects.
Pro
Joined: Mar 2006
Posts: 704
Likes: 0
From: Somewhere I Belong! OutSide
coming Thursday similar bolt ons gonna be installed in my '04 Z06 so videos and dyno numbers will be shared as well too 
Pro LG LT's w/o cats + X Pipe
Borla Stinger Cat-Back
Vararam V-B2 intake
Underdrive Pulley
MSD 8.5mm wires with TR55 spark plugs
the Cam for sure will be later this year
it got 365rwhp / 358rwtq --- BONE STOCK
Peace
Pro LG LT's w/o cats + X Pipe
Borla Stinger Cat-Back
Vararam V-B2 intake
Underdrive Pulley
MSD 8.5mm wires with TR55 spark plugs
the Cam for sure will be later this year
it got 365rwhp / 358rwtq --- BONE STOCK
Peace
Melting Slicks
Joined: Jan 2008
Posts: 2,532
Likes: 364
From: NSL UT
I'll be looking for that for that, My bolts on the watch list. It was loose when I got the car. I have a gm bolt to go back in, but I guess that while I am at it I should do a arp bolt and a upgraded pulley. I think that car already has a cam, it pulls harder than other Zs that I drove and had LTs and a Fast 90 as well.
Melting Slicks
Joined: Aug 2000
Posts: 2,618
Likes: 5
From: Overland Park KS
I would recommend you pin the crank/pulley. It helps prevent the pulley from spinning if the bolt comes loose. There are a couple different kits you can buy that help you do it yourself. If you do a search you should find a lot of info on it.