LIL SS

iTrader: (9)

So on my 418ci motor in my truck, I do not run anything but an alternator. Is there a pulley out there that is made that only has the front belt grooves? I'm thinking there is rotating weight there I don't need.

I currently have a Camaro ASP UD Pulley so I'd prefer to keep the same belt depth but not afraid to move my alternator forwards or backwaeds if needed.

garygnu

try ATI or fluiddampener.

Mighty Whitey

Oh, you mean one like this??





ney-Sayers tend to tell you that rotational mass that close to the center of the mass doesn't account for much. But it's hard to argue with a balancer that's 6lbs lighter than stock!

LIL SS

iTrader: (9)

Is that a stock unit that you machined down?
I'm assuming it was rebalanced?
Do you run this unit?
If so, how many miles or trips down the track are on it?
Any problems that you have experienced?
Did you have any back to back testing, either at the track or on the dyno?

Mighty Whitey

Yes, it's just a stock fbody unit that I put on a lathe, indicated to +/- .0005" TIR, and started cutting on.

As far as balancing, I "static" balanced it (mandrel through the center, saddled on a set of precision rollers and checked for the "heavy" spot to fall to the bottom.) the factory balance job isn't that great, and if anything, I feel that my balancer is runs a little truer than stock.
No,the one in the pictures has not been put in use as of yet, but I gave another balancer I had the same treatment back in 2006, and it's made 15, sub-9.50 runs, and atleast 20, 7600rpm pulls on a chassis dyno without issue.

Unfortunately, the test vehicle that received the modified balancer had quite a few things changed all at once (from stock block h/c/i, to forged 347, new cam, 1.5 points in CR, and a th400 to glide swap) so I can't attest to any differences on that specific vehicle.

In the next few months I'll get a back to back dyno comparison. I have a stock one, and this one I'll try out. If I see any improvements on the dyno, I'll go ahead and test them at the track as well, since the real benefit of less rotational mass would be RPM acceleration in the lower gears.

If nothing else, it's a good conversation piece, it's another 6 pounds off the nose of the car, it's better looking, and it's easier to remove with a 3-jaw gear pulled than a stock one is.

I've also cut a stock truck balancer down, suprisingly I dropped somewhere close to 10lbs off of it. It's a featherweight now!

LIL SS

iTrader: (9)

I'm wondering if the same can be done with an ASP pulley or one that is already smaller in diameter than a factory one.

Mighty Whitey

I see no reason why not. I actually had a local guy ask me if I would do just that to his asp pulley. I told him I would, but just hated cutting up a $300+ balancer