'70 front discs onto '66 Impala - Impala Tech
Brakes & Suspension Conversion Questions & more

 
LinkBack Thread Tools
post #1 of 7 (permalink) Old 10-31-2015, 07:35 PM Thread Starter
 
 
Join Date: Apr 2014
Location: NE Ohio
Posts: 13
 
'70 front discs onto '66 Impala

Hi guys,
Haven't posted much at all but now my project is finally underway so I'll be asking plenty of questions.
I've done some searching but still need to ask about putting front discs on my '66. I have the spindle assemblies, calipers, front disc brake hubs and booster/MC assembly from a '70 Impala. I've been reading as much as I can about how this is done. I need the front rotors yet and plan to go with the C3 Corvette rear rotors.
Seems to me I've read to use the steering arms from the '66 drum brake spindles onto the '70 disc brake spindles. Yes, they bolt right up but the problem is that they only bolt to the '70 spindle with the center two bolts. The '70 steering arms are longer towards the front so that the backing plate and front part of the caliper bracket can bolt to this portion of the arm. Obviously the '66 steering arms don't have this. But that extra mounting hole is definitely needed to secure that part of the caliper bracket. The logical thing to do would be to just use the '70 steering arms. But is that going to screw up the complete '66 steering assembly since the '70 arms are also a little longer at the rear where the outer tie rods connect? I have a new '66 pitman arm, center link and idler arm. Will these work with the '70 steering arms?
The bare frame is back from the blaster and has been primed and painted and I'm hoping to start assembly within the next week or so. I'm also going to be using new tubular upper and lower control arms from POL if that helps the discussion at all.
I know there are others here who have done this particular conversion and would be grateful for any advice on what to do about this. I realize my question is asking about a potential steering issue but since it relates to the front brake conversion I'm doing I hope it's OK that I posted in this part of the forum. I also realize there is probably a very simple answer that I'm completely overlooking. For me that would be par for the course.
Thanks very much for any help.

Denny
impala4speed is offline  
Sponsored Links
Advertisement
 
post #2 of 7 (permalink) Old 10-31-2015, 08:10 PM Thread Starter
 
 
Join Date: Apr 2014
Location: NE Ohio
Posts: 13
 
Here's some pics that might help, '70 arm above, '66 arm below in each pic:
Attached Thumbnails
Click image for larger version

Name:	051.jpg
Views:	88
Size:	32.0 KB
ID:	13033   Click image for larger version

Name:	052.jpg
Views:	92
Size:	44.8 KB
ID:	13041   Click image for larger version

Name:	056.jpg
Views:	94
Size:	44.8 KB
ID:	13049  

Denny
impala4speed is offline  
post #3 of 7 (permalink) Old 11-01-2015, 12:24 AM
Moderator
 
Join Date: Jan 2006
Posts: 12,458
 
I was under the impression that 1969-'70 Impalas used a different sized version of the single piston full floating caliper for their disc brake option. The 1967-'68 Impala used a Girling fixed bridge four piston caliper similar to the Corvette. (I don't remember disc brakes being offered as an option in 1966 but I could be mistaken).

The factory didn't trust the smaller sized A-body, F and X body disc brake system to stop the heavier Impala car. The lighter cars used a smaller sized piston and rotor that were offered as an option for the first time in 1969. So for 1969 and 1970 there is the possibility of using either disc brake system if you can find all of the parts.

Big Dave
Big Dave is offline  
 
post #4 of 7 (permalink) Old 11-01-2015, 07:05 AM
Senior Member
 
Join Date: Apr 2014
Location: North Dakota
Posts: 132
 
Garage
Quote:
Originally Posted by impala4speed View Post
Hi guys,
Haven't posted much at all but now my project is finally underway so I'll be asking plenty of questions.
I've done some searching but still need to ask about putting front discs on my '66. I have the spindle assemblies, calipers, front disc brake hubs and booster/MC assembly from a '70 Impala. I've been reading as much as I can about how this is done. I need the front rotors yet and plan to go with the C3 Corvette rear rotors.
Seems to me I've read to use the steering arms from the '66 drum brake spindles onto the '70 disc brake spindles. Yes, they bolt right up but the problem is that they only bolt to the '70 spindle with the center two bolts. The '70 steering arms are longer towards the front so that the backing plate and front part of the caliper bracket can bolt to this portion of the arm. Obviously the '66 steering arms don't have this. But that extra mounting hole is definitely needed to secure that part of the caliper bracket. The logical thing to do would be to just use the '70 steering arms. But is that going to screw up the complete '66 steering assembly since the '70 arms are also a little longer at the rear where the outer tie rods connect? I have a new '66 pitman arm, center link and idler arm. Will these work with the '70 steering arms?
The bare frame is back from the blaster and has been primed and painted and I'm hoping to start assembly within the next week or so. I'm also going to be using new tubular upper and lower control arms from POL if that helps the discussion at all.
I know there are others here who have done this particular conversion and would be grateful for any advice on what to do about this. I realize my question is asking about a potential steering issue but since it relates to the front brake conversion I'm doing I hope it's OK that I posted in this part of the forum. I also realize there is probably a very simple answer that I'm completely overlooking. For me that would be par for the course.
Thanks very much for any help.
I did this swap on my 66 Impala using the 70 spindles, disc brakes, master cylinder, booster and brake lines. I used my 66 upper and lower control arms. Everything bolted up nice and worked but lost steering radius. Could not turn as sharp when parking and so on. Could have probably worked on grinding down the stops but lived with it for many years. I have since installed CCP drop spindles and front disc brake kit in my car. Braking is no better but I like the stance much better.
6366 is offline  
post #5 of 7 (permalink) Old 11-01-2015, 09:41 AM
Moderator
 
Join Date: Jan 2006
Posts: 12,458
 
Disc brakes add to the track of the front end moving the wheel tire further out as much as 5/8th of an inch depending upon with which parts were used to set them up. The stops can be ground down but the steering gear box has internal stops that controls the turning radius (something to remember if swapping out a steering gear box off of another vehicle). The external stops cast into the spindle are in case the internal stops are bumped out of adjustment. If you look at them they are all rusty and should have never hit if your steering box is adjusted correctly. If the metal id shiny and dark with evidence of spalling then the stops are hitting.

Big Dave
Big Dave is offline  
post #6 of 7 (permalink) Old 11-01-2015, 11:13 AM Thread Starter
 
 
Join Date: Apr 2014
Location: NE Ohio
Posts: 13
 
Thanks Big Dave for the replies. I agree in using the bigger disc brakes that GM designed for these big cars. I'm also going to be running a big block and although this car is intended for street driving and not racing I just feel better with the bigger brakes up front as compared to one of the conversion kits that use the smaller A-body size brakes. I'm sure the conversion kits work very well but I still want to use this '70 Impala set-up.

6366, I appreciate the info. Sounds like your set-up works very well. I'm assuming then that you used the '70 steering arms that went with the '70 spindles? I'll go that route and if any issues with turning radius I can grind down stops as you and Big Dave have suggested.

Thanks for the help guys.

Denny
impala4speed is offline  
post #7 of 7 (permalink) Old 01-13-2016, 10:02 PM
Senior Member
 
Join Date: Dec 2006
Location: Las Cruces, NM
Posts: 136
 
Corvette rear brakes

there is a pair of heavily damaged late C3 Corvettes at the West El Paso U pull it. Don't know if these suspension parts have any "core" value, but they have been sitting, attached to these carcasses, for close to six months now. If anyone has interest, PM me.
Attached Thumbnails
Click image for larger version

Name:	100_5299.jpg
Views:	79
Size:	46.5 KB
ID:	13594   Click image for larger version

Name:	100_5300.jpg
Views:	86
Size:	44.7 KB
ID:	13602   Click image for larger version

Name:	100_5296.jpg
Views:	72
Size:	54.9 KB
ID:	13610  
newmexguy is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Impala Tech 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










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



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