1977 impala th400 swap - Chevy Impala Forums
Impala 1st - 5th Gen Discussion 1958-1985. Discuss all Chevy Impala 1st Gen - 5th Generation Performance and Technical Discussion here.

User Tag List

Reply
 
LinkBack Thread Tools Display Modes
post #1 of (permalink) Old 03-01-2018 Thread Starter
Senior Member
 
Stockcar10's Avatar
 
Join Date: Jan 2018
Posts: 127
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Thanks: 4
Thanked 19 Times in 17 Posts
1977 impala th400 swap

anyone know how much you have to take out of the drive shaft on a 1977 impala aero coupe when swapping out a th350 for a th400?
car already has a 8.5 10 bolt in it.

also anyone have a p/n for the slip you for the transmission

any help would be appreciated

1977 impala Aero Coupe White
Turbo LS/TH400 Disc Brake Conv.
1977 Impala Aero Coupe Red
Bone Stock 305 2bbl on Studded snow tires
1978 Malibu Landau coupe
"Mini-Me"
2015 F250 Platinum CCSB
Stockcar10 is offline  
Sponsored Links
Advertisement
 
post #2 of (permalink) Old 03-09-2018 Thread Starter
Senior Member
 
Stockcar10's Avatar
 
Join Date: Jan 2018
Posts: 127
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Thanks: 4
Thanked 19 Times in 17 Posts
anyone at all?
Stockcar10 is offline  
post #3 of (permalink) Old 03-09-2018
Senior Member
 
hatzie's Avatar
 
Join Date: Nov 2009
Location: Baker River Valley, NH
Posts: 954
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 157 Post(s)
Thanks: 83
Thanked 150 Times in 132 Posts
Any driveshaft shop should be able to get you the TH400 Yoke.
Google is your friend...

2009 Impala SS
"Speed never killed anyone. Suddenly becoming stationary... that's what gets you." Jeremy Clarkson
hatzie is offline  
Sponsored Links
Advertisement
 
post #4 of (permalink) Old 03-09-2018 Thread Starter
Senior Member
 
Stockcar10's Avatar
 
Join Date: Jan 2018
Posts: 127
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Thanks: 4
Thanked 19 Times in 17 Posts
Quote:
Originally Posted by hatzie View Post
Any driveshaft shop should be able to get you the TH400 Yoke.
Google is your friend...
Yeah i can get a yoke, but im just curious if shortening of the shaft is even needed. Rather just getting a th400 short snout yoke. theres about 11/16" difference in a th350 short shaft to a th400 short shaft
Stockcar10 is offline  
post #5 of (permalink) Old 03-09-2018
Senior Member
 
hatzie's Avatar
 
Join Date: Nov 2009
Location: Baker River Valley, NH
Posts: 954
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 157 Post(s)
Thanks: 83
Thanked 150 Times in 132 Posts
If your TH400 is the same length as the old TH350 you shouldn't have to change the shaft.

If the TH400 is a different length you'll have to install it and measure.
How to Measure for the Correct-Length Driveshaft - Hot Rod Network

2009 Impala SS
"Speed never killed anyone. Suddenly becoming stationary... that's what gets you." Jeremy Clarkson
hatzie is offline  
post #6 of (permalink) Old 03-19-2018 Thread Starter
Senior Member
 
Stockcar10's Avatar
 
Join Date: Jan 2018
Posts: 127
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Thanks: 4
Thanked 19 Times in 17 Posts
Quote:
Originally Posted by hatzie View Post
If your TH400 is the same length as the old TH350 you shouldn't have to change the shaft.

If the TH400 is a different length you'll have to install it and measure.
How to Measure for the Correct-Length Driveshaft - Hot Rod Network
yeah the yoke is different diameter and the trans is longer.
just dont know how much i need to change just yet

1977 impala Aero Coupe White
Turbo LS/TH400 Disc Brake Conv.
1977 Impala Aero Coupe Red
Bone Stock 305 2bbl on Studded snow tires
1978 Malibu Landau coupe
"Mini-Me"
2015 F250 Platinum CCSB
Stockcar10 is offline  
post #7 of (permalink) Old 03-19-2018
Super Moderator
 
Dwayne J's Avatar
 
Join Date: Jan 2009
Posts: 3,877
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 84 Post(s)
Thanks: 16
Thanked 362 Times in 234 Posts
if street or street/strip a TH350 should handle anything but a knarly bigblock and if swapping for a street car I would only consider a overdrive transmission.

TH400 is overly heavy and may actually slow down a street/strip car.

The LS swap could have moved the tranny location some too so I would measure not rely on a published number unless that number is published with your full swap kit for that engine in that car with that transmission.

Dwayne
96 Caprice with AI 200cc package
Best et 11.5
Best MPH 116
Just another taxi
Dwayne J is offline  
post #8 of (permalink) Old 03-19-2018
Senior Member
 
hatzie's Avatar
 
Join Date: Nov 2009
Location: Baker River Valley, NH
Posts: 954
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 157 Post(s)
Thanks: 83
Thanked 150 Times in 132 Posts
Quote:
Originally Posted by Stockcar10 View Post
yeah the yoke is different diameter and the trans is longer.
just dont know how much i need to change just yet
Yeah the yokes are different.

Longer trans means shorter driveshaft. Easier than needing a longer shaft.

Once you have the measurement(s) needed...
And assuming you don't have any other issues.
You can get a driveline shop to shorten and balance your old shaft. I'd have them install your new TH400 slip yoke and put in brandy new U-joints before they balance it.

2009 Impala SS
"Speed never killed anyone. Suddenly becoming stationary... that's what gets you." Jeremy Clarkson
hatzie is offline  
post #9 of (permalink) Old 03-19-2018 Thread Starter
Senior Member
 
Stockcar10's Avatar
 
Join Date: Jan 2018
Posts: 127
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Thanks: 4
Thanked 19 Times in 17 Posts
Quote:
Originally Posted by hatzie View Post
Yeah the yokes are different.

Longer trans means shorter driveshaft. Easier than needing a longer shaft.

Once you have the measurement(s) needed...
And assuming you don't have any other issues.
You can get a driveline shop to shorten and balance your old shaft. I'd have them install your new TH400 slip yoke and put in brandy new U-joints before they balance it.
yeah thats the plan, possibly have them build a HD shaft

1977 impala Aero Coupe White
Turbo LS/TH400 Disc Brake Conv.
1977 Impala Aero Coupe Red
Bone Stock 305 2bbl on Studded snow tires
1978 Malibu Landau coupe
"Mini-Me"
2015 F250 Platinum CCSB
Stockcar10 is offline  
post #10 of (permalink) Old 03-19-2018 Thread Starter
Senior Member
 
Stockcar10's Avatar
 
Join Date: Jan 2018
Posts: 127
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Thanks: 4
Thanked 19 Times in 17 Posts
Quote:
Originally Posted by Dwayne J View Post
if street or street/strip a TH350 should handle anything but a knarly bigblock and if swapping for a street car I would only consider a overdrive transmission.

TH400 is overly heavy and may actually slow down a street/strip car.

The LS swap could have moved the tranny location some too so I would measure not rely on a published number unless that number is published with your full swap kit for that engine in that car with that transmission.
looking to push 7-800 to the tire, but my th350 failed becuase i was scammed an didn't get a built trans. is what it is and im moving onto a better setup. and the swap plates put it in the same location but yes your correct the drive shaft will have to be moved to make up for the longer trans

1977 impala Aero Coupe White
Turbo LS/TH400 Disc Brake Conv.
1977 Impala Aero Coupe Red
Bone Stock 305 2bbl on Studded snow tires
1978 Malibu Landau coupe
"Mini-Me"
2015 F250 Platinum CCSB
Stockcar10 is offline  
post #11 of (permalink) Old 03-19-2018
Super Moderator
 
Dwayne J's Avatar
 
Join Date: Jan 2009
Posts: 3,877
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 84 Post(s)
Thanks: 16
Thanked 362 Times in 234 Posts
At 700wheel then yeah a TH400 becomes a reasonable idea and you don't need the lower first gear something like a 4L60 would get you.
A properly built TH350 should handle the soft power delivery of a turbo though but finding someone to reliably build one locally is likely getting hard since that tranny has been out of OEM production probably 35years.

What mount kit did you use?

YEARS ago I dismantled my 96 Caprice with the intent of a turbo LQ4 swap, then "life" happened and it has sat since.

Dwayne
96 Caprice with AI 200cc package
Best et 11.5
Best MPH 116
Just another taxi
Dwayne J is offline  
post #12 of (permalink) Old 03-19-2018 Thread Starter
Senior Member
 
Stockcar10's Avatar
 
Join Date: Jan 2018
Posts: 127
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Thanks: 4
Thanked 19 Times in 17 Posts
Quote:
Originally Posted by Dwayne J View Post
At 700wheel then yeah a TH400 becomes a reasonable idea and you don't need the lower first gear something like a 4L60 would get you.
A properly built TH350 should handle the soft power delivery of a turbo though but finding someone to reliably build one locally is likely getting hard since that tranny has been out of OEM production probably 35years.

What mount kit did you use?

YEARS ago I dismantled my 96 Caprice with the intent of a turbo LQ4 swap, then "life" happened and it has sat since.
yeah that what i was figuring. yeah i didnt really want the 4l60e just from the build price point.. about 6-800 more than the th400. Around here not many people like messing with the th350 for these kinds of builds.

an mount kit, im guessing you mean turbo mount kit? I custom fabbed the entire turbo kit, minus the manifolds
no time like the present to start!
Stockcar10 is offline  
post #13 of (permalink) Old 03-19-2018 Thread Starter
Senior Member
 
Stockcar10's Avatar
 
Join Date: Jan 2018
Posts: 127
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Thanks: 4
Thanked 19 Times in 17 Posts
[IMG][/IMG]
[IMG][/IMG]
[IMG][/IMG]

intake has changed since then, going to change it again

1977 impala Aero Coupe White
Turbo LS/TH400 Disc Brake Conv.
1977 Impala Aero Coupe Red
Bone Stock 305 2bbl on Studded snow tires
1978 Malibu Landau coupe
"Mini-Me"
2015 F250 Platinum CCSB
Stockcar10 is offline  
post #14 of (permalink) Old 03-19-2018 Thread Starter
Senior Member
 
Stockcar10's Avatar
 
Join Date: Jan 2018
Posts: 127
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Thanks: 4
Thanked 19 Times in 17 Posts
Quote:
Originally Posted by Dwayne J View Post
At 700wheel then yeah a TH400 becomes a reasonable idea and you don't need the lower first gear something like a 4L60 would get you.
A properly built TH350 should handle the soft power delivery of a turbo though but finding someone to reliably build one locally is likely getting hard since that tranny has been out of OEM production probably 35years.

What mount kit did you use?

YEARS ago I dismantled my 96 Caprice with the intent of a turbo LQ4 swap, then "life" happened and it has sat since.
[IMG][/IMG]

1977 impala Aero Coupe White
Turbo LS/TH400 Disc Brake Conv.
1977 Impala Aero Coupe Red
Bone Stock 305 2bbl on Studded snow tires
1978 Malibu Landau coupe
"Mini-Me"
2015 F250 Platinum CCSB
Stockcar10 is offline  
post #15 of (permalink) Old 03-20-2018 Thread Starter
Senior Member
 
Stockcar10's Avatar
 
Join Date: Jan 2018
Posts: 127
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Thanks: 4
Thanked 19 Times in 17 Posts
trans guy called yesterday, going to go pick it up this afternoon in colorado

1977 impala Aero Coupe White
Turbo LS/TH400 Disc Brake Conv.
1977 Impala Aero Coupe Red
Bone Stock 305 2bbl on Studded snow tires
1978 Malibu Landau coupe
"Mini-Me"
2015 F250 Platinum CCSB
Stockcar10 is offline  
Sponsored Links
Advertisement
 
Reply

Related Threads
Thread Thread Starter Forum Replies Last Post
impala 1981 wagon 496 bbc tall deck swap! rockabilly66 Chevy Impala 6th Gen Discussion 0 04-12-2019 05:46 AM
Rear end swap on a 72 impala from a 96 impala ss Gemale11 Impala 1st - 5th Gen Discussion 1 03-20-2019 07:26 PM
1977 Chevrolet Impala RSS Bot eBay Cars For Sale: Impala 0 07-08-2018 01:51 PM
1977 chevy caprice door pillar trim impala RSS Bot Impala Diecast Toys Cars on eBay 0 08-27-2017 05:40 PM
1977 Chevy Caprice Chrome Seat Trim Mounding 1978 1979 Impala Box Chevy Interior RSS Bot Impala Diecast Toys Cars on eBay 0 08-23-2017 11:30 PM


Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevy Impala Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in













Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome