Well I'm slowly getting my tranny back together,not easy when you can only work on it on the weekend,and every section turns up wrong parts.First it was the wrong selective plate for the low reverse clutch ,now the steels for the forward and reverse input clutch packs are wrong....So while I have to get different steels for those clutch's should I swap out the 3-4 clutch pack for the 9 disc upgrade ?

 

I would consider the 9 disk or the ZPACK

 

cool thanks

 

I would go with a 8 clutch set up. I feel that the steels in both the above suggested packs are to thin. Because of this they worp and start dragging the clutches. I have see this many in of my competitions units over the years and feel that the clutch pack we use works very well. Keep in mind that I have tested the others and tested 1 of them before it was even on the market. The Zpack was designed for towing and not high peformance. Vince

 

I whole heartedly agree with Vince. In our experience the Z-pack or Red Eagle 9 clutch set up is significantly inferior. Use an 8 clutch setup using thicker steels in the 3-4 clutch. I have a stack of burned up thin clutches darn near a foot high, we had tried many variations of those clutches in vain when developing our race units. They simply do not hold up to anything over 375 h/p or an engine that spins over 5,500 rpm... they just don't. Heat kills them, the thin steels warp or cone up and that causes the clutches to stay applied or rub the steels when not engaged and that friction causes more heat and they burn up in a very short period of time.

Use Borg Warner high energy or Alto Red clutches and you'll be just fine.

g

 

thats some good info thank you.I just went to Transtar and got the correct steels,good thing the Zpack was on back order.I'll order a 3-4 set from FLT

 

I just checked and for some reason I have 8 alto red disc for the 3-4 set and 6 steels can I just get one more steel and new apply and presure plates to make the 8 setup

 

What thickness are the frictions and steels that you got from tstar? You will need .062 frictions with .078 steels. I will use a thicker friction to tighten up the pack if needed and or make a change with the apply plate or pressure plate. It is very nice when you have a lathe in the back of the shop to help accomplish this.

 

I hear that,the new lathe won't be here for maybe another month or so,oh well the frictions are .080 and the steels are .106 so I'll just call you in the am to order what I need. Thanks Vince

 

As HP goes up, the ability to make a 2-3 WOT shift get harder. About 10 years ago we started to use the 4L60E .080" Borg Warner 2nd design Hi-Energy clutches in the 3-4 clutch pack. I would use 8 clutches and the .062" - .078" steels, .128" pressure plates, .062" snap ring, this setup was very successful.

About 5 years ago I started to use the BW Hi-E 4L65E .065" clutches and would make a 9 clutch setup. Clearance would be .040" - .055" on the 700R4, and .025" - .035" on the 4L60E. This 9 clutch 3-4 pack has seen many hundreds of passes in 9 & 10 second vehicles, and I have found none better than this for highest HP (700+ fwhp) applications. Both of these clutch packs have worked out very well in terms of longevity.

I have found that the clutch material is of more importance than the thickness of the steels in high HP drag racing or straight line applications. The clutch needs to hold a certain amount of oil to help get rid of the heat on the 2-3 WOT shift, if it cannot get rid of the heat, then you will burn the clutches, which in turn overheat the steels. Remember when the 2-3 shift occurs (the paper clutch (under pressure) trying to match the speed of the steel clutch in apx. 2-3 tenths of a second) the oil instantly "vaporizes" from the clutch material, if there is not enough oil in the clutch material, then the problems start.

In Road Racing the steels need to be thicker also, to help dissipate the heat, they act as a heat sink. All 3-4 clutch packs will cone to some degree, and this is normal and is mainly caused from the heat not being released fast enough.

 

Says who? Where did you get this mystical 375 hp limit for these clutch setups? We use the Z-Pak all the time. I have yet to see ONE fail. My own 96 Chevy pickup truck has one in it. It makes 600hp TO THE WHEELS, and weighs 4500lb. I shift at 6200 RPM. I abuse it more than most people and the Z-Pak has been in there for 2 years without a problem. I also tow with it all the time as much as 10,000 lbs. 375 hp is a joke, especially in a lighter weight F-body.

 

We also use the Zpack and have for a couple years and have not seen this coning issue or any of them other wise break , In fact what I have seen is just the opposite. In a couple cases where the PCS had failed causing low line i have seen where the set has gotten so hot it blued but it was still flat and actually would have been quite usable if someone had chosen to do so.
In fact the only case I have seen where they coned they had been miss assembled and someone had put the top spacer steel upside down on the bottom and since it serves more purpose than just a spacer it was understandable ,
On the matter of heat even if it was developed for commercial applications which would mean fleet cars and commercial light trucks delivery vans ect with stock shifts . Nice and smoothe which would generate alot more heat that a sudden impact shift like a performance unit should have which would only tend to support the fact they can take the heat.
As for RPMs I don't see how that would affect it at all other than the 4l60e is known to centrifically apply the 3-4 clutch at high RPM but this is addressed with the aux springs in the drum and in other ways,
On the matter of the thicker steels dissipating heat faster ?they have the same surface area externally as the thin ones and heat dissipation is determined by surface area. agreed there might be a couple 1000 th extra in the thickness area on the edge but overall with the greater internal area of the steel with virtually the same area for heat dissipation I would say they would cool slower than a thinner counter part.
Now I will say this it is true that the thinner steels will warp more easily if they get to hot from slipping but then they shouldnt be slipping in the first place.
In addition on the Z pack by design it would tend to hold less heat since rather than having non conductive material on both sides of a steel plate actually acting as and insulator every clutch has a steel side exposed to fluid so cooling should be better.
That added to the material used as a friction medium and they have 30 percent more holding than the oem high energy so are much less likely to slip and generate the heat in the first place.
I looked all over Raybestos site for a 375 hp limit and then I called there tech support and they had never heard that either.
We have units both high performance and commercial heavy duty that have been out there for years with the Z pack. The only thing I would love to see and I mentioned it when I spoke with tech support was the IDEA of the blue plate material on the Zpack design because of the materials very aggressive friction properties.
Anyway My 2 cents. For now we have found there service excellent and have yet to see and failure due to the clutch set itself.
link to a video that may be of interest to some below
http://www.raybestospowertrain.com/...t_zpak_mov.html

 

Relax guys my comments are based on my personal experience... I happen to think the Z-Pack is a good idea and a good product in the proper application... but I will not put it in another high performance application myself. I have seen them slip on the chassis dyno during pulls while watching line pressure... checked for cross leaks very diligently during the teardown, in a unit that had a HD-2 kit running a modulator. This was in a controlled environment, in a car that is very consistent, and on a Dyno Dynamics chassis dyno. I cannot speak to your experience. I religiously use Raybestos components every chance I get and have for over 20 years, I'm not bashing them nor their product, who am I to do that?... but I'm out on the Z-pack. I will say this... during our testing we did see that the Z-pack lived much longer than other thin steel thin clutch combinations. Our first Z-pack lasted well over 2 months before failing, and when it came out the steels were coned. Still have 'em.

I too have spoken with Raybestos tech support folks and they are very helpful, but at the end of the day I cannot in full confidence put a Z-pack in one of my customers high performance cars at this point in time, that is a personal experience based comment. We burned several different stacks up during pulls at 5500+ RPM's in 3rd gear, not locked up, in a car that at the time was capable of that horsepower level. After installing an entirely different clutch setup in the same unit without replacing anything other than frt pump and valve body plate paper we made successful pulls and since then have many of these living in many cars. Again, it's simply an experience based comment as yours is.

The comment about the thicker steels was simply a general comment, again based on experience, about the ability of a thicker piece of metal being able to withstand heat stresses, without distorting, better and longer than a thin piece of metal. We've all seen thick steels warp, bent metal is not an anomally in automatic transmissions. My goal of using heavier thicker components is to give the weakest link in the transmission a stronger foundation from which to operate... thats it.

I am not an engineer, don't protest to be the end all be all tranny builder, am quite humble about my work and have had my hat handed to me more than a few times just like anyone else who challenges his skill level every day. I know what works for me and my customers and what has not worked... we go with what works for us and don't mind talking about it.

g

 

As do we, And we are constantly on the lookout for something better than what are using and ways to improve the use of the products we are using presently also.
I spend extensive time studying whats out there and whats new and then considering the advantages and disadvantages of each. Cost for us is generally not and issue since we can simply raise the price and compensate and explain to our customers why it is better,
There are even presently several new products and ideas we have been looking into and will continue to improve our products as we find proven products that are significantly better in our opinion.
We never trash our competitors each has something they have found that works for them and we think thats great. We also watch our competitors and listen to what they say as I'm sure they do us because you never know when you can learn something new.
And like you I have had my hat handed to me and strangely I like when that happens because hopfully at the end of the day I have learned something knew. I am on these forums everyday not only helping people but watching and learning. When I see a knew idea I study it carefully and if i think its a good one I submit it for review to our production people as I am the tech and the one who gets to do that lol.
I like when people post up in a civil manor as to why they think there way is better and I may have a different opinion I will state, But you will never hear PerformaBuilt put down anothers product in this forum or any. Thats not how we do business and i apreciate the way you put your take on things.
We to are proud of what we produce here at PerformaBuilt and don't mind talking about it though we do avoid conflicts but a good discussion is great anytime.

 

I have the z-pack in my trans and have ohhhhh 50 passes on it all over 375hp. Actually transman built mine, love it!