clwz28

I am getting my parts together to build my 94 4l60e,I am wondering do I need the shorter #7 apply ring to install a z-pak?or does my tranny already have the #7 apply ring?

PedaltoMetal

If it's out of a Z car it should have it. Especially if it has the "golden rooster".
It'll have a "7" on one of the legs where it meets the base.

performabuilt

iTrader: (25)

The ZPACK comes with everything you need except of course the retaining ring it comes with one but ussually its to thin IMO to get the right clearance in the clutch pack.

clwz28

How many retaining ring options are they.

PedaltoMetal

I found two different ones but there may be others.
.062
.089

spaz1

iTrader: (9)

I think you want to set it at about .016" clearance.

clwz28

stock is .075-.078 right?I read z pak comes with .062,maybye one or the other will get the clearence in range.

performabuilt

iTrader: (25)

IMO Clearance should be between 0.20 and 0.30
Neet trick - the ZPACK comes with a new top plate instead of it use the stock top plate with the retainer ring they supply. Many times it will be right on the mark.

clwz28

sounds good

WE TODD DID

iTrader: (2)

You don't have any problems with centrifugal apply of the clutches when running them that tight?

performabuilt

iTrader: (25)

We have noted none to date

WE TODD DID

iTrader: (2)

Do you drill a bleed hole in the drum, under the 3-4 piston? I'm just curious, as I have little experience with high hp builds on the 4L60 transmission. I've built probably 1000 stock to mild units.

performabuilt

iTrader: (25)

No but we do use either the TG stiffer springs or the factory square helper springs depending on the clutch set up to offset that issue. But as I said we have not really noted any issues with that. The few 3-4 clutch failures we have see were generally traced to some other underlying cause.

355z28

iTrader: (8)

Your running that tight of clearance dry I take it? Just wondering since they recomend clearance set at .040-.050 I think. Do you run most of your clutch sets tight except for reverse? Thanks!

The first zpak I recieved had several retaining rings, the most recent one I recieved only had one and made it impossible to get the clearance I needed. All late model 60s come with the #7 apply ring.

I use the Red alto with kolene steels. The 9 friction set up. Clearance is recomended .020-.035 and no problems to date.

As far as 3-4 burnup, the HD2 kit comes with a few updates to fix it.

performabuilt

iTrader: (25)

The 3-4 set is run with the tightest clearance in our unit and yes that it a dry setup on a build. After running on the dyno its actually opens up some. In fact simply applying it during the air check several times will generally open it up .05 or more . I have noted that .020 becomes .030 aprox after the dyno runs.