Dynamic396

Yes, I see that cup plug blown out occasionally. It is usually on a unit that has had max line pressure commanded by the PCM and has been subjected to numerous max line pressure shifts. The factory drives them in from the outside (input shaft side) and then "kinda" stakes them in place. They can eventually pop out.

That orifice you're talking about is part Transgo's kit. They have you remove the check ball capsule and install their orifice plug. I don't use them. I just don't see their benefit. It's just another leak, in my opinion. I do drill an orifice to relieve centrifugal apply on high rpm applications, but not in that location. That location is just not optimal for either a centrifugal apply orifice or an air bleed orifice.

I have, thankfully, never left out that o-ring, but I have seen others do it. They were never very happy when it happened...

fst100

iTrader: (5)

nothing to really update as of yet. his friend/my neighbor believes firmly on it's valvebody related.

fst100

iTrader: (5)

update! buddy says the forward sprag was the culprit and took a dump. he's getting a new one and hopefully get it buttoned up and finished. what would cause it to go bad?

mrvedit

Glad you found the reason.
Make sure the builder uses the HD Borg Warner sprag.

I would highly recommend also installing the Sonnax HD 2-3 shift valve; this will keep the overrun clutches engaged in [D3] so that you can use [D3] at the track. The overrun clutches share load from the sprag.
(Otherwise when you race in [D3] the overrun clutches are only engaged as the trans shifts to 3rd, depriving the 3-4 clutch of fluid during the shift (bad).
I can find more threads on this if you need, but many builder consider this shift valve a MUST.

fst100

iTrader: (5)

i believe he is using some sort of sonnax in his builds.

mrvedit

There are many useful Sonnax parts. The HD 2-3 Shift valve is this:

http://www.sonnax.com/system/announcement/77754-41.pdf

Here is one thread discussing the importance of the valve and that the chart in the ATSG manual in wrong with regard to the overrun clutch. (Due to this error, many builders overlook the importance of this valve for performance runs.) In my post #15 I show the correct chart in the GM technical manual.

https://ls1tech.com/forums/automatic...-drive-od.html

Here is another thread of many on the subject:

https://ls1tech.com/forums/automatic...-question.html

IMHO, confirm with your builder that this valve is being installed. Note that it requires a mod (drill hole) in the valve body. You will feel the difference in [D3], but the valve has no effect on [OD] for routine driving.

With the valve installed, do your drag racing in [D3].

fst100

iTrader: (5)

i was told that the valvebody parts he's using are pre-drilled and everything's good to good. he is using the BG HD sprag fwiw. i trust him in his parts he's using.