Direct Drum

[ACLR8R]

Hey, my tranny guy says I need a direct drum. What are my options Im a college student and really dont have the $500 to drop on a billet one. Is there anything else? What about a heat or cryo treated stocker? Just wondering what you guys think.
Thanks

 

[V6POWER]

Look here: http://www.bulkpart.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=2&Category_Code=200-4Rdrums

They have used ones for $54.65. You don't need a billet. What is wrong with yours?

 

[ACLR8R]

Its warped, and I need something tougher than factory. So I was wondering if there was anything between factory and Billet?
Thanks

 

[bison]

Its warped, and I need something tougher than factory. So I was wondering if there was anything between factory and Billet?
Thanks

I doubt you need something tougher than the factory one. Many members on this board have gone in the 10's with a factory one and some have gone 9's. If its warped it got too hot. It didnt warp because of torque. You may be referring to the factory forward drum splined shaft. This is a common breakage point in a 200-4R trans. If this is what you are referring to then it will cost around $500. What performance level are you at? It is easy to build a 200-4R that will survive with the stock forward drum down to 11.50.

 

[ACLR8R]

I'm not sure that is what my tranny guy said. It’s only a mid to high 11 sec car. He said it is the direct drum, it’s where the band rides; he said the band is warping it, not excessive transmission heat.
Is he calling it the wrong thing? is it the forward drum splined shaft?
Thanks

 

[jakeshoe]

The drum the band rides on is the direct drum.

Think about this for a second...
The drum is made of metal, the band is a friction material that is paper based.

Do you really think the band is warping the drum?

Heat is warping the drum, and if there is enough to warp the drum, the band is probably burned up too.

Maybe you are using a kevlar band. I would use an Alto Red instead if thats the case.

You need to get a GOOD drum. Either an excellent used refurbished one or a new GM unit.

I take the good used ones and turn them on a lathe, then polish them while on the lathe. That way I have a good smooth flat surface for the band to grab.

Your builder should be able to do this or buy one alredy done.

Several vendors here offer ready to go drums.

 

[V6POWER]

Here is what Bruce (WE4) says about direct drum:

*DIRECT DRUM:
The direct drum must be within .030 of original diameter. Cannot be bent or heat deformed. DO NOT drill holes in band surface. This does nothing but add problems with band oil, the direct clutches slinging their lube out, and I have even seen them crack from the holes, and distort the actual drum itself.(Like a brake rotor) Weakens them immensly. All steels must slide freely in bore. In ring bore, no ring cavities can be present. One of the most common 2-3 flair symptom is , bore is ring grooved near bottom of drum using cast iron rings. Band surface must be PERFECTLY FLAT, no scores, especially with the use of the new band. Teflon rings are recommended and almost a must.
USE OF MULTI or EXTRA CLUTCH PACKS HIGHLY NOT RECOMMENDED!!!!!
The theory does not work. You will cook them,every time. We have spent countless hours testing theories and clutch materials. With the steels at .090 or thicker in stock form,they work perfect. 6 Clutches with stock steels set to .038-.042 end clearence will work flawless!!!!!! We recommend Alto Red Eagle clutches for stock and hd rebuilds, and Raybestos Blue Plate clutches for street/strip and strip use. ( Again, use of Kolene steels is not recommended. Stock .090 and thicker stock steels are just fine and must be flat.)* Update: Alto is working on a brand new steel for this application. We will keep you posted.
Direct drum good to whenever mid 9's.

 

[ACLR8R]

jakeshoe:
I think it does have a Kevlar band in it. Could this be causing the warping? Should I switch to an Alto band and find a new drum?

 

[bison]

jakeshoe:
I think it does have a Kevlar band in it. Could this be causing the warping? Should I switch to an Alto band and find a new drum?

I never use Kevlar bands in the 200 4-R. Kevlar tends to beat up the drum more than anything. The latest design Alto red is the way to goand its cheaper than a kevlar one. Maybe your drum is already way undersize. It wont apply correctly if its too small and will quickly burn the band and drum. I turn the drums like jakeshoe does, but you have to be sure there is no run out and dont go over .030 of factory diameter. 6.180in is the original dimension. Usually .010 is plenty to get a good surface. It should be smooth but not a mirror. If you cut the drum you must check the servo clearance because it will increase. I have never warped a drum or had one warp in anyones trans i did. Most of them are in the 10's.