Jump to content

85 720 brake upgrade


E.T.

Recommended Posts

Hello everyone , new to the forum.

got my self a good deal on a 85 720 for $500 . Body is a little rusty . But I've replacing all the suspension . Shocks bushings, ball joints etc.

my question is , is there a way I could get bigger rotors and calipers on the front ?

Link to comment
  • Replies 8
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Sweet! So all I have to do is find calipers from the hardbody and bolt on to the 85 ? Correct?

 

I do know that it is an upgrade, as I have a set on my work truck, but all the specifics escape me at the moment.

The 85/86/hardbody single piston calipers are good brakes, it's what Mike K. is using on his disc brake conversions, it's what I want on all my drivers, parts are cheap and available, and will be for a long time.

Do not go out and buy dual piston calipers right now, I am having brain lock, if it was that easy every one would do it, I will ask Mike K and get back to you on the specifics, or maybe he will see this thread and comment.

Link to comment

Wayno was close, but the 720's before 10/85 had different rotors than the HB, but the same calipers.  He's correct as long as your 720 is from the end of the year.

 

The dual piston caliper has the same bolt spacing on the mounts, so with no rotor in the way, I think they bolt up fine.  But, they have a different offset from the single piston.  I think Yello620 would know the answer better.   I think you can put the v6 rotor and caliper(which is the dual piston) onto your hub/spindle. 

 

As far as fitting, the hubs are the same and can be interchanged between the 620(disc), 720, and HB.  The only thing that really changes between them is the hub registration hole size required on the wheels. 

 

The v6 caliper is about 10mm bigger diameter and is thicker.  The hub registration hole that it aligns with on the back of the hub is the same as is the bolt pattern. 

 

Check with yello on this.........and if stock rims will fit if that's what you're running.

  • Like 1
Link to comment

Thankyou Mike, and for information purposes that might clear up my, ah, ah, fuzzyness on this is that the dual piston caliper setup I mentioned I had on my work truck was purchased complete from the said member yello620.  :lol:  :lol:  :lol:

 

I did learn that I could bolt the said rotor on my early 81/82 hub and put it on the spindle, and install the dual piston caliper, and then use very early 520/521 14 inch rims after adjusting the inside of the rims with a hammer which seemed to have no effect on the rim, 620 disc brake rims need no such adjustments.

Link to comment

I believe that all you should need to do is get rotors and calipers at this point. Get rotors and calipers for a 1990 Nissan 2WD V-6 pickup.

 

Make sure that the 720 has a master cylinder large enough for the dual piston calipers. You need a 7/8" or 15/16". The larger master provides a firmer pedal, but more effort from the driver. I found the 15/16" master pedal feel in my 620 to be just right for my liking. But I do not know what the 720 used for master size, though 7/8 stock would not surprise me.

  • Like 1
Link to comment

And there you go, everything you need to know for a dual piston caliper upgrade, and now I can do the same thing with confidence also.

I only have one vehicle with this upgrade, as I have found that the vented rotor brakes work just fine with the single piston calipers, but I just drive them, I don't haul stuff around with them like I do with the work truck.

My work truck that has the dual piston upgrade.

DSCN0392.JPG

 

DSCN0393.JPG

Link to comment
  • 2 weeks later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.