|
|
TF 727 Valve body check ball questions
#260334
03/20/09 10:46 PM
03/20/09 10:46 PM
|
Joined: Aug 2005
Posts: 759
Southington Ct.
turbobitt
OP
super stock
|
OP
super stock
Joined: Aug 2005
Posts: 759
Southington Ct.
|
OK , this may be a stupid question and/or beaten to death, but I can't find anything in the tech archives. Why do some shiftkits remove some of the checkballs and others do not ? I am interested in making this shift as hard as possible for that "Hot rod" feel. This is a manual shift VB that I'm working on. I was comparing an old set of Fairbanks instructions to a set of Transgo instructions and noticed that one of the small checkballs is omitted for "Competition use" in the Fairbanks kit.
Allan G.
1970 Challenger w/572 Hemi street car and my pride and joy.
1986 T-Type with 272 Stage 2 Buick V6 engine - True 8 second street car. Just updated the engine and put down 928 HP @ 35# boost to the ground on chasis dyno.
1976 Cee Bee Avenger Jet Boat - 460 Ford powered.
|
|
|
Re: TF 727 Valve body check ball questions
[Re: turbobitt]
#260335
03/20/09 11:30 PM
03/20/09 11:30 PM
|
Joined: Dec 2007
Posts: 10,542
BROOK PARK, OH
WILD BILL
Senior Member of the Junior Dragster Club
|
Senior Member of the Junior Dragster Club
Joined: Dec 2007
Posts: 10,542
BROOK PARK, OH
|
Your wanting to modify a manual shift VB? 
|
|
|
Re: TF 727 Valve body check ball questions
[Re: turbobitt]
#260336
03/21/09 01:34 PM
03/21/09 01:34 PM
|
Joined: Jan 2003
Posts: 25,720
Rio Linda, CA
John_Kunkel
Too Many Posts
|
Too Many Posts
Joined: Jan 2003
Posts: 25,720
Rio Linda, CA
|
Removing the #6 check ball (the one in the "D" shaped pocket) allows the maximum amount of fluid flow to the kickdown servo and the firmest 1-2 shift. There are two schools of thought on this, one school says that's good and another says it's not so good; thus the difference in kit makers instructions.
When using a VB with rear band apply the maximum fluid flow often causes severe overlap on a manual 1-2 upshift since the rear band just can't release as quickly as the kickdown band applies. Leaving the ball in place and adjusting the size of the servo feed orifice makes for a good firm shift without the overlap. Also removing the ball and/or blocking the accumulator makes the trans shift so hard that it can shear the splines in the aluminum front pinion carrier.
Depending on the year there can also be check balls in the transfer plate, one slows the application of the rear clutch and the other slows the application of the rear servo, this is intended to prevent parts breakage and has no adverse effect on performance. I've never understood why some kit makers have you remove them, no advantage that I can see unless you're trying to rock a stuck car by rapidly shifting from "R" to "D".
The INTERNET, the MISinformation superhighway
|
|
|
Re: TF 727 Valve body check ball questions
[Re: turbobitt]
#260338
03/21/09 05:53 PM
03/21/09 05:53 PM
|
Joined: Jan 2003
Posts: 543
Indiana, Just Off I-70
BradD
mopar
|
mopar
Joined: Jan 2003
Posts: 543
Indiana, Just Off I-70
|
John, are you saying the old trick of the accumulator blocking rod is a bad idea?? I definitely like a firm shift without tearing up parts!
Check out the Dorn's 69 Barracuda "Switchblade" in the Nov.2010 MCG
Check out the Dorn's refurbished 36 Ford in the Feb.2011 Street Rodder
|
|
|
Re: TF 727 Valve body check ball questions
[Re: BradD]
#260339
03/21/09 07:25 PM
03/21/09 07:25 PM
|
Joined: Jan 2003
Posts: 5,987
Anoka County, MN
Leigh
master
|
master
Joined: Jan 2003
Posts: 5,987
Anoka County, MN
|
Quote:
John, are you saying the old trick of the accumulator blocking rod is a bad idea?? I definitely like a firm shift without tearing up parts!
Kunkle's favorite topic.  
|
|
|
Re: TF 727 Valve body check ball questions
[Re: Leigh]
#260340
03/22/09 02:57 PM
03/22/09 02:57 PM
|
Joined: Jan 2003
Posts: 25,720
Rio Linda, CA
John_Kunkel
Too Many Posts
|
Too Many Posts
Joined: Jan 2003
Posts: 25,720
Rio Linda, CA
|
Actually, the accumulator SPRING is my favorite topic, while I don't advocate using the blocker rod I do recognize that it does firm the shift.
Since the rear servo releases through spring pressure only it can't release at the same rate as a hydraulic servo of near the same size can apply. Even if the buttmeter doesn't feel it, there is overlap if the servo feed is unrestricted. If you jack the rear wheels clear of the ground and manually shift from 1-2 at around 1500 rpm you will most likely see the rear wheels come to momentary stop due to the overlap.
The INTERNET, the MISinformation superhighway
|
|
|
|
|
|
|
