ninetyfivevette

Subject says it all... I am not sure how one would use an underdrive pulley on an LT1 application since the pulley and harmonic balancer are the same piece. The only reason I ask is because I may have trashed my balancer getting it off and it seems like the underdrive pulley kits are cheaper than a new balancer.

Thanks for any advise!

Mike

Zora

Nope :nonod:

racerns

The balancer bolts to the outside of the underdrive pulley. If you want to shell out the bucks you can get a Fluidamper and it will give you some underdrive and replace you current balancer.

ninetyfivevette

Thanks for the information. I was not sure how it would work.

I guess then an underdrive pulley would be totally worthless from a performance gain perspective because most of the gain is from reducing the mass on the flywheel, not the actual underdriving of the accessories.

Is there any advantage to using a Fluidamper versus the stock balancer? I don't plan on much high RPM use (<= 6200).

Thanks again :cheers:

Mike


[Modified by ninetyfivevette, 4:50 AM 1/24/2003]

racerns

The gain from the uderdrive pulley is supposed to come from reduced drag from not spinning you accesories as fast. Not really sure if there is really much of a gain there, a few hp at best. I got one because the f-body ps pumps tend to over heat at extended high rpm (roadcourse) and the underdrive slows the pump down enough to keep it from over heating. If you are not spinning very high I doubt that a Fluid damper would be worth it. See if you pick up a stock balancer from a junk yard.

FRC2000

the underdrive pulley DOES replace the balancer on an LT1. i have no idea what others are saying it doesnt. the pulley/balancer is 1 piece on the LT1. Ive used March pulleys twice, and now an asp pulley, ive switched them quite a few times. I know on the March pulley the rubber dampener is on the inside of the peice that bolts to the hub and the piece the belt goes around. ANyhow, When the stock balancer is off, it is replaced by a 1 Piece underdrive pulley that acts as a balancer as well. Try ASP pulleys, cheaper priced than the March and it looks like 1000% better in terms of build quality.

FRC2000

wait i get it, thats a camaro hes talking about. those cars have both, on the Vette it is 1 piece. Notice how March pulley kits are 4x the price for the vette ones compared to the camaro ones. :cheers:

aggie88

QUOTE]....I may have trashed my balancer getting it off and it seems like the underdrive pulley kits are cheaper than a new balancer.[/QUOTE]
I hope this is not a "hijack" on the subject. But I will clearly answer the pulley - balancer issue on the 95 LT1 Corvette. I found out the hard way about the integrated pulley/balancer design of the LT1. I bought a 2piece ASP underdrive pulleys and tried to install them on my 95 LT1 Vette. Not being able to remove the oulley/balancer, I had to return them back to ASP. Is it possible to take off that pulley/balancer with the engine in the car? I coud not find a way to use a balancer puller with the engine in the car, the steering rack sits directly in front of it! How did you do it?[

388 SOLid RoLLeR

heres what i did. I too put on the asp pullies. The stock ba;lancer is stubborn and a pain to get off with a puller. didnt work for me with the dam tool. Id advise not to hammer it either or it will damage. i loosened the 3 bolts holding the balancer to the hub, and tightened them back leaving a tiny slack so the pulley had minor play. I marked the Balancer to the hub (so i know how to position the new one), and i started the car for 1 second intervals. the vibrations shook the pulley a little loose and then i wiggled it off :D :cheers: :cheers:

Rick93Z07

388's method above is very effective for removing stubborn dampeners, wheels rotors and drums that are rusted on. The key is to: 1) loosen the fasteners just a couple turns to allow slight clearance/movement & 2) keep checking bolt clearance & keep runtime to a bare minimum so the part doesn't come off or cause damage from wobble.

In the case of a real stubborn dampener, blipping the throttle with A/C ON to add serpentine accessory load will help. Check the 3 bolts after each startup/shutdown cycle to confirm they're only 1 or 2 turns loose. I think this method is basically fullproof unless you run the motor for more than 15 sec or something. You should be able to tell when the dampener has come loose. At least one of the 3 bolts will become tighter when the dampener breaks loose.

For wheels, rotors & drums, low velocity and stabbing the brake moving forward and reverse will do it.


[Modified by Rick93Z07, 8:42 AM 1/25/2003]

ninetyfivevette

Those all seem like good methods, but chances are, if you are removing the balancer, you have a lot of the "guts" removed that would be otherwise needed for the car to run... Unless of course you did things to specifically allow the engine to run, but why make more work for yourself then necessary?

Just get a small gear puller (yes GEAR puller) to pull the balancer off of the hub. You will be using the arms of the gear puller on inner part of the hub. I pulled mine off like this in about 2 minutes where I had previously spent 2 weeks trying various methods to no avail. The gear puller trick was suggested to my by a fellow forum member and I HIGHLY recommend it.

Also, you mentioned clearance between the steering rack... You may have to raise the engine slightly. Just remove the lower motor mount nuts and lift it by the oil pan, but be sure to put a piece of wood that is fairly large to cover most of the bottom of the pan to spread the load. Probably not the best way, but I did it that way with no ill effects. Then notice there is a little "loop" on the power steering line in the top middle of the steering rack... This is your area to slide the puller's bolt through.

The above method saved me TONS of time and again, I highly recommend it!

Mike

FRC2000

That seems like a lot of work to me. Only guts to remove for my way is the belt, thats it.
1. remove the belt.
2. loosen boltson pulley
3. start motor briefly
4. take pulley off

that doesnt seem hard does it? :cheers:

ninetyfivevette

It is hard for me to remember since I tore mine apart so long ago and my intentions were to strip the compartment down enough to do a cam swap and install headers.

My balancer was on so tight anyway, I am not sure just starting the engine would do it... Guess I'll never know!

racerns

Sorry for the misinformation guys, I guess I did not realize the difference. I will say that the stock balancer on the f-body is integrated as the acc. drive pulley but the aftermarket underive pully set up I have gives you a pulley that slips over the hub and the the stock balancer is bolted in front of it. I don't remeber what brand it is since I have had it for so long. Not sure why that setup would not work for a Vette unless you don't have the room in front there.

FRC2000

id guess its for clearance issues as well. The vettes has barely enough room to get a wratchet in there to loosen the bolts on the pulley. Thats why they made it a 1 piece. BTW that camaro looks awesome! :cheers:

Rick93Z07

Seems to me you can crack loose the 3 dampener pulley bolts without removing any hardware....not even the belt. You can fish a 3/4" breaker bar & socket in from the passenger side, under the P/S reservoir.

ASRoff

Try "lots" of penatrating oil and let it sit over night I just receved an ASP harmonic balancer nice piece the center section is aluminum and the outside is steel. (I bought it because Im having the rotating assembly balanced) The balancer has a refrence mark machined on it to install it correctly all you do is line it up with the arrow on the hub.

89'Bowtie

How much is an ASP unit for the Y-Body LT1? Who is ASP, do they have a webpage?

Victor


[Modified by 89'Bowtie, 9:10 PM 1/29/2003]

aggie88

At the risk of being accused of hijacking:

Auto Specialties Performance at http://www.aspracing.com They work out of a small office warehouse in the Houston area. Great folks to deal with. Quality stuff, they even do custom one-offs.

[QUOTE]How much is an ASP unit for the Y-Body LT1? Who is ASP, do they have a webpage?[QUOTE]