Drivetrain Clutch, Torque Converter, Transmission, Driveline, Axles, Rear Ends

Is a pro shifted t-56 any different that a shift kitted auto?

Old Jul 12, 2004 | 01:39 PM
  #1  
95Bird's Avatar
Thread Starter
Registered User
 
Joined: Jan 1999
Posts: 989
From: Baton Rouge, la
Is a pro shifted t-56 any different that a shift kitted auto?

just wondering what people think. If you pro shift your t-56 is that any different than putting a shift kit in a 4L60E? Before you give a knee jerk reaction..think about what you gain from each modification.
Old Jul 12, 2004 | 03:24 PM
  #2  
Loadre's Avatar
Registered User
 
Joined: Jul 2001
Posts: 1,887
From: Kingsport, TN
A shift kit basically does nothing besides firm up shifts. I don't know what you mean by pro-shift (powershift?)
Old Jul 12, 2004 | 03:39 PM
  #3  
95Bird's Avatar
Thread Starter
Registered User
 
Joined: Jan 1999
Posts: 989
From: Baton Rouge, la
basically it gets rid of the syncros so you don't tear them up so much.
Old Jul 12, 2004 | 06:28 PM
  #4  
95Bird's Avatar
Thread Starter
Registered User
 
Joined: Jan 1999
Posts: 989
From: Baton Rouge, la
does anyone else even know what a pro shifted t-56 is?
Old Jul 12, 2004 | 10:33 PM
  #5  
Jim_H's Avatar
Registered User
 
Joined: Feb 2002
Posts: 96
From: WI
If you think about it, you really aren't losing any e.t. in shifting whether the car is pro-shifted(no synchros) or not(with synchros). The majority of the e.t. difference is in the 60 foot times and a little farther out to the 330 foot mark. You will still be dumping the clutch to get out of the hole.

I would say if your goal is to break less parts, then the pro-shifted option may be worth it. You seem to be a hardcore drag racer. Ifoyu aren't you will hate driving the car on the street without synchros.
Old Jul 13, 2004 | 01:03 AM
  #6  
1racerdude's Avatar
Banned
 
Joined: May 2003
Posts: 6,661
From: LA (lower Alabama)
Pro Shifted is basically a "crash"box,yank and go.Upshift's well but no way to downshift those "dog" ring's. Some are clutchless,no need for clutch to upshift.
Same thing Mr 4 Speed--Ronnie Sox use to use in the '60's and '70's Made it sound like an automatic.(rowing the boat)

Last edited by 1racerdude; Jul 13, 2004 at 01:06 AM.
Old Jul 13, 2004 | 02:35 PM
  #7  
95Bird's Avatar
Thread Starter
Registered User
 
Joined: Jan 1999
Posts: 989
From: Baton Rouge, la
so is that an advantage over say a shift kitted auto? And you cant go clutchless on our trannys. Its still a clutch assisted shift.
Old Jul 13, 2004 | 02:47 PM
  #8  
1racerdude's Avatar
Banned
 
Joined: May 2003
Posts: 6,661
From: LA (lower Alabama)
A crash box will be faster,an auto will be more consistant.Uhhhh who will know about the clutch unless you are taking rider's with you down the strip.A clutchless tranny looks like a normal tranny from the outside,but very easy to spot with the cover off.
Old Jul 13, 2004 | 03:09 PM
  #9  
95Bird's Avatar
Thread Starter
Registered User
 
Joined: Jan 1999
Posts: 989
From: Baton Rouge, la
what I'm trying to see is if people think that a pro shifted t-56 would warrent it being outlawed in a racing class where big stalled autos with shift kits are legal.

Think about it. With a pro shifted tranny you get quicker firmer shifts, it makes the tranny stronger since you have no syncros to tear up, And trust me...you better use the clutch in our trannys or that pro shifted setup will be going back for a rebuild very quick. A guy I know thought he didn't need to clutch it and it lasted 1 race. Now think about what you get from putting a shift kit in an auto, quicker firmer shifts, makes it stronger since it doesn't "slip" as much between shifts and burn the clutches up. Should one be allowed and not the other?
Old Jul 13, 2004 | 03:18 PM
  #10  
1racerdude's Avatar
Banned
 
Joined: May 2003
Posts: 6,661
From: LA (lower Alabama)
Well you answered your own question.The crash box does have an advantage.As far as the clutch goes you DON'T need it if the tranny is a true crash box.I had a T-10 that was used for 4 years without a clutch,behind a 427 big block.If a tranny is just piddled with and called "pro" shifted,who knows.
Joe Liberty at Liberty Trans can tell you all about a real pro shifted tranny he makes them,call him and get the scoop.
Old Jul 13, 2004 | 03:30 PM
  #11  
95Bird's Avatar
Thread Starter
Registered User
 
Joined: Jan 1999
Posts: 989
From: Baton Rouge, la
yea...the car I'm talking about is liberty pro shifted production t-56..they say to use a clutch. I agree a TRUE crashbox clutchless tranny is better...but on ours you still have to use a clutch to make upshifts. But since our t-56s have to still use the clutch would a pro shifted really be an advantage enough to outlaw it in a racing class. Its really a "shift kited" manual tranny if you think about it. They both do the same thing.
Old Jul 13, 2004 | 04:08 PM
  #12  
1racerdude's Avatar
Banned
 
Joined: May 2003
Posts: 6,661
From: LA (lower Alabama)
A stick is more positive in it's RWHP.It don't have converter slip,clutch slip,ETC.The few miliseconds in 4 shift's makes for a maybe .5 at the finish line and it is very hard to miss a shift.There is a 50-60RWHP difference in a 500FWHP set up with both cars being equal.Also the auto's have to have a built tranny and by convertered right to get close. I think they are just trying to level the field.
Old Jul 13, 2004 | 04:23 PM
  #13  
95Bird's Avatar
Thread Starter
Registered User
 
Joined: Jan 1999
Posts: 989
From: Baton Rouge, la
did you mean .05 or .5 because there is no way a pro shifted car is worth 1/2 a second. I agree wtih it being worth half a tenth. If you have 15% loss on a manual and 20% loss in a auto..thats 20 rwhp at 500 fwhp. I knwo that when I race a big stalled auto even when we cut the same 60' he will put about 3-4 cars on my by the 300 ft mark because of the converter slippage and torque multiplication. Look at the record holders for heads/cam cars and it will show that at high hp levels an auto needs no help over a manual...pro shifted or not. Ive seen bolt on converter cars outrunning built motor manual cars. I'm just wondering how a tranny that you still have to use the clutch to make shifts is such an advantage over a 4500 stall, shift kitted, full manual valve body 4l60e?

Last edited by 95Bird; Jul 13, 2004 at 04:26 PM.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
RUENUF
Cars For Sale
1
May 25, 2016 08:10 PM
RUENUF
South Atlantic
4
Mar 13, 2016 03:39 PM
jb4xx
General 1967-2002 F-Body Tech
9
Feb 2, 2015 10:00 PM
tds1213
General 1967-2002 F-Body Tech
1
Nov 27, 2014 12:55 PM


Thread Tools
Search this Thread

All times are GMT -5. The time now is 07:01 AM.