Classic Mustangs (Tech) Technical discussions about the Mustangs of yester-year.

Transmission indecision 2012

Thread Tools
 
Search this Thread
 
Old Mar 10, 2012 | 03:37 PM
  #1  
rusty65's Avatar
rusty65
Thread Starter
1st Gear Member
 
Joined: May 2011
Posts: 59
From: FL
Default Transmission indecision 2012

Hey guys, long time no see.

I finally finished my 5.0 HO build, and am itching to get it into the car. Problem is I still need a trans to go behind it. I want to get rid of the old cruise-o-matic that's in there and put in a manual transmission. I did a lot of reading up on the t5 swaps that people are doing and was leaning that way for a while. However, I recently read that the old 'toploader' (?) 4 speeds can handle a substantially greater amount of abuse than the t5's whose torque limit is somewhere around 350 ft lbs if I remember correctly, and I'm going to be making torque somewhere near that ceiling (potentially more), so now I find myself seriously considering a 4 speed. Unfortunately I haven't been able to find very much info on these 4 speeds (searching for top loader) so I was hoping I could get a bunch of my questions answered here....

First and foremost, what keywords should I use when searching the web for 4 speed info? I've been using "top loader 4 speed", but I don't get very many results along the lines of what I'm after (mostly old truck trans stuff). Also, would a 4 speed out of an old 60s ford truck work? Or would the gear ratio be sub-par for my application?

As for the other, I'm gunna get a list going....
Where should I look into getting a 4 speed from if I do go that route?
Will a 4 speed handle highway driving well enough with it's 1:1 4th gear to do on average 4hours of highway driving a month?
Does the 4 speed really offer enough of a durability increase to warrant choosing it over the much more common 5 speed?
Will I need to shorten/lengthen my drive shaft and/or change my yoke if I install the 4 speed?
Would the four speed swap be cheaper than the 5 speed swap, since I'm assuming I wouldn't have to change as many things out (such as my crossmember)?

The guys who built my engine told me to account for about 400 hp and ~350 lb ft when choosing a trans, etc.

Any info y'all can give me would be a big help, and thanks in advance!
Old Mar 10, 2012 | 05:54 PM
  #2  
2+2GT's Avatar
2+2GT
6th Gear Member
 
Joined: May 2009
Posts: 5,232
From: PA
Default

http://www.google.com/search?hl=en&s...6l886l7.3l10l0
Old Mar 11, 2012 | 04:52 AM
  #3  
Boxwrenchesareslow's Avatar
Boxwrenchesareslow
 
Joined: Jan 2012
Posts: 25
From: ca
Default

I think you'd be just fine with a world class T-5.
Old Mar 11, 2012 | 09:09 AM
  #4  
JMD's Avatar
JMD
6th Gear Member
 
Joined: Jan 2007
Posts: 5,469
From: AR
Default

How much do you have to spend?

A TKO 500 or TKO 600 can work with a little bit of work...

There is a slight fit problem at the top of the case on a 65, but this can be dealt with easy enough.

A TKO will give you OD, and be able to handle 500 or 600 lbs of torque.

It will require a new bell housing or an adapter.
Old Mar 11, 2012 | 11:18 AM
  #5  
1969boss302's Avatar
1969boss302
 
Joined: Dec 2008
Posts: 35
From: CT
Default

I ran a 5.0 backed up with a toploader in a '68 Cougar I had several years ago. The toploader is about as bulletproof a 4 speed as you will find. The car was originally an automatic and I was able to use the driveshaft without changing the yoke. I was able to use all of the original clutch linkage with this setup as well. I did run into one major problem with it initially, I originally ran the diaphram cluth that came with the 5.0, but this caused me to break my clutch linkage a few times until I wised up to what was happening and swapped out the proper clutch for the '68. After that I ran the car for 10 years without another problem. I would recommend this setup to anyone as the toploader can handle more abuse/torque than a T-5.
Old Mar 11, 2012 | 11:31 AM
  #6  
2+2GT's Avatar
2+2GT
6th Gear Member
 
Joined: May 2009
Posts: 5,232
From: PA
Default

I prefer to use the stock, semi-centrifugal 10.5" clutch that Ford used in the 289HP and BOSS 302. It'll bolt right onto the stock 64-73 289/302 flywheels.
Old Mar 12, 2012 | 12:12 AM
  #7  
1969boss302's Avatar
1969boss302
 
Joined: Dec 2008
Posts: 35
From: CT
Default

that clutch will work just fine with the toploader setup. There are a few things you should keep in mind when selecting your toploader, there are 28 spline and 31 spline output toploaders out there, the 31 spline were for big block 428's and Boss 429's and have a larger input shaft as well. You don't need one of those a 28 spline output is plenty strong enough for your application. Also the 390 28 spline units have a shorter snout on the input shaft than the small block units, if you get a 390 unit make sure to get a pilot bushing specifically for that application, it's longer than a regular bushing to make up the difference. If you run a 390 toploader on a small block without the right bushing (or swapping out a small block input shaft) you can damage the transmission and possibly lose the input shaft catastrophically.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
4cylinderplus2
V6 (1994-2004) Mustangs
10
Oct 9, 2020 07:45 PM
b8checker
Classic Mustangs (Tech)
8
Oct 8, 2015 12:55 PM
b8checker
New Member Area
3
Sep 30, 2015 07:11 AM
wraith777
General Tech
1
Sep 28, 2015 10:49 AM




All times are GMT -5. The time now is 04:32 PM.