B&M shift kit...plug 3-4 clutch hole?

lt170chevelle · 09-10-2009, 09:22 PM

I am in the middle of rebuilding my 4l60e and decided to get a trans go seperater plate. well i just noticed that the plate that came with a b&m shift kit that i had installed a few years back it had me hammer a plug onto the plate and from what i read is one of three being the biggest hole 3-4 clutch.From the size i am thinking maybe its an exhaust. does anybody know about this mod?
It was one of those cheap 25 buck kits that came with spacers to take the place of the acc springs ,in which i put stiff springs back in since i have heard that the spacers kill the impact absorbtion of the hydraulics.
Idk know if it was ignorance and maybe i some how plugged the wrong hole or if this is what was supposed to be blocked.

lt170chevelle · 09-11-2009, 08:26 AM

Hey guys can you give me some insight on this? I am going to be finishing up my tranny tonight and installing it.

performabuilt · 09-11-2009, 10:18 AM

Unfortunatley I am not so familiar with the B&M kit . I do know we dont plug any holes in our setup.
If you can post a pic or send it to me of the plate with the hole blocked and i will determine what it is.
Frank

lt170chevelle · 09-11-2009, 01:18 PM

Ok i can snap a pic when i get home. This according to my book is one of three holes that are really close together on the plate for the 3-4 clutch. It is a bigger round hole, a small round hole and a square hole. they are almost arranged in a triangular pattern. I dont know if these are for the exhaust or feed.But the bigger round one is the one that it says to plug. Another thing i noticed was it says to drill the feed holes to a 1/4" Wouldnt that be really hard on the internals?
I found an install instructions on it here:

http://rds.yahoo.com/_ylt=A0geu66Yha...9500582-03.pdf

lt170chevelle · 09-13-2009, 11:18 AM

So i nevered figured out the reason for the plug on the vb plate from the b&m kit..so imma leave it off of the new trans go plate and see how it feels.And i was wrong on the square hole. It plugs a check ball hole and leaves that ball out of the vb. it does have a very small hole next to it.

performabuilt · 09-13-2009, 11:22 AM

I tried to look at the link you posted , Its says "This link not authorized by yahoo"

lt170chevelle · 09-13-2009, 08:48 PM

oh just skip passed that. its because the pdf file is on another site i believe.just click to look anyways..its just a security warning
Also i got everything back together and took it for a short drive and either 4th gear or lockup is going in and out ..like a slow pulsation..almost felt maybe electrical?..Its been pouring cats an dogs all weekend so didnt want to drive it to much. I manually shifted it and it felt like i could barely feel 4th shift. but like i said it has been pouring so i was very easy on the throttle. I hope for a drier day tomorrow so i can see exactly whats its doing.

Vince @ FLT · 09-13-2009, 11:04 PM

The plug is located in the third accumulator check ball seat. The check balls primary function is to direct exhausting 3rd accumulator oil to the 3-2 control valve. It basically is used for the 2-4 band apply for a 3-2 downshift. On a 3-4 shift the ball would normally unseat itself with fluid pressure for a quick feed into the 3rd accumulator circuit. This would help the 3-4 clutch stay applied. Thus the reason for enlarging the hole next to the plugged hole. Mean while on the back side of the servo assembly, fluid is being supplied through the servo pin. Then the 4th servo strokes the servo pin to apply the band. If that makes any sense. Vince B

lt170chevelle · 09-14-2009, 01:21 PM

Ok yes that makes sense. So why would plugging it the way b&m shows to do help anything? Wouldnt that just make the 3rd accumulator curcuit not apply as quickly?I understand making the feed hole larger but why block the check ball hole?
Sorry for all the questions, i am just trying to understand the reasoning for it fully.

lt170chevelle · 09-14-2009, 05:43 PM

Hey vince..i am a little confused now that i reread your reply and you mentioned that the hole next to the plugged hole gets enlarged? I thought the 3rd feed hole according to the paper that came with the transgo plate says 3rd is the center most small hole and on the b&m one it says to enlarge that one also.Was i supposed to open up the one next to the hole in question that was plugged?
According to the b&m plate for reference the 2nd, 3rd ,and 4th feed holes get enlarged 3/32 for hd which is what i went with,or a whopping 1/8 for street strip only on 2nd and 3rd.

lt170chevelle · 09-15-2009, 09:12 AM

Update: Went ahead and drove it to work to see what it was doing on the highway. 1-3 is solid BUT 4th is slipping like carazy like its not getting barely any pressure to engage it. I can feel it shift into 4th but if i give anything over maybe 5% throttle the rpms just keep climbing until it hits 3rd gears rpm. Would this be related to the plug in the vb plate? I was really easy on it and kept it in 3rd as soon as i noticed it slipping in 4th.

lt170chevelle · 09-15-2009, 03:20 PM

Possible 4th servo leak?

Vince @ FLT · 09-16-2009, 08:43 PM

Quote:

Originally Posted by lt170chevelle

Ok yes that makes sense. So why would plugging it the way b&m shows to do help anything? Wouldnt that just make the 3rd accumulator curcuit not apply as quickly?I understand making the feed hole larger but why block the check ball hole?
Sorry for all the questions, i am just trying to understand the reasoning for it fully.

Not sure why they do it that way. I have never done it nor tested it. The issue I see is when the release of the ball would occur. Seems to me it would help on one function of the ball but hurt on the flip side of it.

Quote:

Originally Posted by lt170chevelle

Hey vince..i am a little confused now that i reread your reply and you mentioned that the hole next to the plugged hole gets enlarged? I thought the 3rd feed hole according to the paper that came with the transgo plate says 3rd is the center most small hole and on the b&m one it says to enlarge that one also.Was i supposed to open up the one next to the hole in question that was plugged?
According to the b&m plate for reference the 2nd, 3rd ,and 4th feed holes get enlarged 3/32 for hd which is what i went with,or a whopping 1/8 for street strip only on 2nd and 3rd.

My bad on the enlarge of the hole comment. I just went and looked at the directions again and I was wrong.

I wonder if plugging the one hole in question might help with detuning the accumulation. Basically because the feed hole is so large.

Quote:

Originally Posted by lt170chevelle

Update: Went ahead and drove it to work to see what it was doing on the highway. 1-3 is solid BUT 4th is slipping like carazy like its not getting barely any pressure to engage it. I can feel it shift into 4th but if i give anything over maybe 5% throttle the rpms just keep climbing until it hits 3rd gears rpm. Would this be related to the plug in the vb plate? I was really easy on it and kept it in 3rd as soon as i noticed it slipping in 4th.

I really do not think that the plug not being installed would not cause a no 4th gear condition unless you did not install the check ball.

Quote:

Originally Posted by lt170chevelle

Possible 4th servo leak?

That would be my first guess.