nsogiba

2000 FRC C5, 6 speed, currently undergoing an LS3/L92 swap. Rather than reuse the factory LS1 balancer which has a slight wobble, I want to upgrade to a high quality aftermarket unit that will last a very long time. 90% street and highway driving, a handful of track days a year.

From some quick reading it looks like Powerbond and ATI Super Dampers are the two most popular options. Powerbond seems more affordable. Any reason to get one over the other?

Also, should I bother with an underdrive unit? Don't want to underdrive my accessories but would love a quicker revving unit.

burneyr

GM utilizes ATI on their hi performance crate motors, and Pratt-Miller use them on the C5,6,7R race cars. That was reason enough for me.

ATI also sells blems on ebay. If you're not in a hurry, might snag a deal there.

No opinion on underdriven pullies. I went with stock diameter.

93Polo

If I went underdrive I'd go 10% on a daily, I understood 25% was for car with electric water pumps and more track oriented.

Ed Ramberger

Powerbond should be good for a DD.

I think most damage and loose fasteners is from improper installation. I have read on here of people wrapping belts around them, putting blocks under them. The crank is what needs to be held while the bolt is tightened - not the outer pulley of the balancer. Also, use a balancer remover and installer - the stock bolt isn't meant to pull it all the way on and can end up stripping threads.

vettenuts

ATI is also fully rebuildable. The hub and balancer parts are separate.

Regardless of which you use, both have a keyed hub. I would buy the ATI pin kit and use it to pin the hub. It will work with either balancer.

I agree with the above, I spoke with one of the ATI engineers at Carlisle years ago and he said to stay at stock or 10%.

nsogiba

I assume a different belt length (shorter) will be required with a 10% UD? Anyone have a part number?

f6john

Just for information purposes. Holley also offers the ATI balancer with their upgraded mid mount FEAD system they developed for ls swaps. I went with their standard kit which I believe included a power bond balancer.

Smoken1

I had Power bond pulley and the belt sizes were listed on the box

bigmackloud

I went with a 10% UD ATI pulley for my current build. I plan to use the car for more track days, so I decided it was worth the extra $$. I believe ATI lists the correct belt sizes on their website.

As mentioned by others, the PB balancer should be fine for street driving.

And with either, I recommend an ARP bolt. (the factory one is TTY, so it should not be reused)

nsogiba

I bit the bullet and purchased the 10% underdrive ATI Super Damper, to be secured with an ARP reusable bolt. Go big or go home!

https://www.summitracing.com/parts/ATI-917278

bigmackloud

They are pretty straight forward, but here's a video I made on assembling the ATI damper.

The instructions say you should a Torx Plus bit.... and you should. However, since you are only going to 16 ft/lbs, I managed to use a regular Torx bit (I was in a time crunch and was too impatient to wait for a new bit set to come in). But be careful because it is loose fitting compared to a Torx Plus bit.

93Polo

Be sure to get the plus torx bits mentioned in the video, do NOT use your standard torx bits. The pain isn't getting it on using the standard bit but getting it off should you ever have to pull it.

I also like using a LS crank holder/stop when torquing the crank bolt.


If you replace the front cover seal, I would use an alignment tool such as SAC City pieces you can find on the forum.

SaberD

I replaced the torx fasteners with stainless hardware. The metal is really soft on the fasteners it comes with, they rust easily, and they get chewed up pretty quickly after a couple installs.

I had to redo mine because my cam sprocket bolts backed out after not applying red Loctite. Luckily I knew what the issue was when I got a cam sensor code - dodged a bullet there.

ASRoff

nsoigba,

here you go... everything you have ever wanted to know about harmonic dampers (they are not "balancers" unless they have weight added to them)

http://www.enginelabs.com/?s=harmonic+balancers