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I cannot find a disc conversion listed anywhere for the 4th gens. What application do they share with? Also, any success stories or misery stories regarding this swap? Thank you....!!!:cool: Is this in the wrong spot?
 

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a popular conversion is the use of 78-82 Trans-Am disc backing plates, ya use the T/A calipers or Deville calipers. the rotors are T/A for the 5x4-3/4 pattern or the Deville for a 5x5 bolt pattern...

you can use the Seville backing plates but then ya need the Seville calipers as the bolt span is a tad wider for the Seville as compared to the T/A-Deville... rotors used are same T/A-Deville.

also

i believe a non disc axle's centering hub is .160 smaller in diameter than a disc axle... so a .080 sleeve will need to be pressed on centering hub for proper fit axle hub to rotor center hole...

or Classic Performance Products has a rear disc kit for 10-12 bolts... quite a few companies making rear disc kits... there's a few links found in the originality forum's sticky... "the Web-Link Library"



hope i helped...
 

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Yep exactly right. I got a 79 trans am rear end with a posi unit, with the better carrier to be able to run my 3:73's. But i had to swap everything into a different housing because the trans am housing is i believe 2-4 inches wider and will not fit under the nova. I got a 8.5 chevy housing out of another nova that worked. Had the seals redone, and bought new axels and had richmond gears 3:73's installed as well. Since my car is mini-tubbed i had to put the spring mounting brackes inward.

Oh, and i also bought new calipers and rotors for it. And had got new posi-clutches installed.

I should have just gone with a 9 inch. Oh well, i now have one stout street rear end with posi and now my car is all wheel disc brakes.

Need any more info let me know.

Rennskii
 

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I am working on installing the rear disc's from an 82 Eldorado on my 75. It will be a little while before it is done. I'l post pictures and results then.
 

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So it seems the ones for the 8.5 rear will work as far as kits. I just noticed when you see the listings, the late novas are not mentioned, only the cars with coil rears are mentioned. Does this make a difference on brakes? Sorry for so many questions about the same thing, I just wish companies would list all applications, rather than assuming everybody already knows! Someday we will all be cool like that!
 

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the plates'll bolt onto any GM differential. on my 55 chev i had ta undo the leaf perch on the right side and lift housing to get at one of the caliper bolts to change pads, had ta modify the e brake cable ta work properly, but the mods were very easy and no biggie.


the caliper has a return spring built in the actuator... the stock e brake cable has a small spring would around the cable, this spring ya carefully cut or grind and UN wind from the cable... it's no longer needed...

a few guys i heard, in regards to the caliper bolts rotated the plates slightly on the housing, marked and re drilled the mounting holes to get the caliper bolts away from any obstruction... no biggie on that either...


it's really a bolt on conversion...

back in the late '70's/early '80's HotRod magazine did a 3 issue article on rear disc conversions... "Stopping on a dime" i still have the mags... i installed the rear discs using the info they put in the mags... since then i've used the exact same conversion on 2 other cars... very good conversion... IMO
 

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There's also a guy on ebay sells bolt-on kits for a little over $400 complete with rotors, calipers, pads, brackets and e-brake setup. I bought a set a while back, but haven't installed them yet. I will be doing that this weekend hopefully. I know they use 78-82 Camaro calipers and rotors per the instructions that came with them.

There's a set listed on ebay now, just do a search for 75 Nova and refine it in side bar for disc brakes and it should come up. He's based out of California with a business, and I believe the phone number is listed in the auction.

I've referred a couple other guys to him and they were satisfied with the setup. One of the guys just bought a set of brackets and I believe he told me he paid $90 for them, and went and found the calipers off a 78 or 79 Camaro and used them.
 

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jade76 said:
I've referred a couple other guys to him and they were satisfied with the setup. One of the guys just bought a set of brackets and I believe he told me he paid $90 for them, and went and found the calipers off a 78 or 79 Camaro and used them.
Are these using FRONT calipers from Camaros ?

I've seen kits before ( popular with monster truck guys ) that use those and no e-brakes.

There was NOT a 78-9 camaro offered with disc brakes on the rear from GM, only Trans-Ams.

Possibly it uses 88-9 (3rd gen ) F-body rear calipers ? ( not as big, but readily available ) .

I;m using the Seville setup on my 76, but have not installed everything, so will keep posting when we get to it ( soon, I hope, but got sidetracked, lol )

~ AL
 

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I could of been mistaken, I'll have to go back and make sure. I was pretty sure the instructions stated it used Camaro calipers and brake pads, I may have the years mixed up.

I started my conversion yesterday but haven't finished yet. I have to remove the axles to remove the drum brake backings to bolt up the caliper brackets.

I figured since I have to remove the axles, I might as well remove the carrier and pinion gear and install my posi unit while I have it broke down this far. I'll post pics when finished, hopefully by Monday since tomorrow's Fathers Day.
 

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I bought the Brackets off EBAY. Tells me to use the Metric Caliper for no E-brake ( anything GM Front I think 80 or 81 Up ) S-10s or Camaros work if you want E-brakes you use Cadilac rears
Also you use 79-81 rear Trans-Am Rotors for 4 3/4 Bolt pattern rear Caddy for 5 bolt pattern
Here is Link to the ones sold on EBAY
http://steeltechsolutions.com/REAR_DISC_PAGE_CODE.html
I too have everything to do my rears cept I have to deal with my Race Axles, The axle end Flange where the studs are is bigger than factory, Have to have them cut down, But will soon. Anybody else who has put this setup on would you show pics for us who haven't done ours yet Thanks
 

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I finally installed mine yesterday and there wasn't nothing to it once I got the axles and drums removed. I had to stagger them to clear the shocks, so the right side is facing the back and left side facing forward. I haven't hooked up the e-brakes yet so I'm kind of wondering how that's going to work out with the stagger.

I'll take some pics tomorrow since it was a little late when I finished and didn't get a chance to take any.

Anybody know if 7.5 axles will work on 8.5 or are they different size? Figured I'd ask before I go tearing apart another rearend. My right axle is wore flat on one side where the inner bearing fits around it and some pretty serious pitting all along the shaft. I really don't want to reuse it. The left side looks great. I'm guessing the right axle was the drive side that took all the torque abuse to be worn down that way.
 

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on one of my conversions, i needed to remove the "ball" at the end of the cable, shorten cable then have a sleeve slid over cable and brazed to get the correct length. it was no biggie. on a Camaro conversion, after unwinding the spring i found the cable was just fine as-is... maybe it'll be the same on yer Nova.

i'd recommend retaining the E-Brake. ya may never need it but ya never know. what would happen if ya DID need it and ya had none ???

could be yer own butt ya save... or someone elses.
 

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badone07 wrote:
Doubt the 7.5 axles will work. Mainly due to the size and splines of the spider gears. Most 7.5's had 26 splines but some 88 and up had 28 splines. The 8.5 has 28 splines until changed to 30 in 88.

You most likely will have to have the axles' outter flange turned down to fit the rotor. I take a notch out of each bracket to make removing easy, without having to remove the axle. However, I retain all 4 mounting holes. Usually from the lower quarter of the bracket.
I was thinking 7.5 was different too, just wanted to see if anyone else has done it. I have another 8.5 I was going to redo, but I guess I'll have to take one of the axles out of it for now. It would be pretty stupid IMO to put a worn axle back in if I have a better one. I'd hate to rebuild this rearend just to have the axle break on me when I go to lay some rubber.

The brackets I bought are bolt-on and I bolted them behind the flange and are easy to get at with the wheels off and the rotors that came with my kit fit beautifully. I bolted the first bracket in front of the flange at first but caliper didn't fit over rotor properly so ended up bolting behind the flange and everything worked out.

JohnnyRotten wrote:

i'd recommend retaining the E-Brake. ya may never need it but ya never know. what would happen if ya DID need it and ya had none ???
Definitely keeping the e-brakes. It will predominently see street use and most states require e-brakes to be street legal. Mine are getting a little modification though. I removed the stock e-brake assembly and putting in a hand brake out of an 88 Camaro. I have buckets out of a early 80's Cavalier or something similar, and tucking it between the 4 spd console which is getting modified for my B&M Hammer Shifter, and driver seat, so it won't be seen unless engaged.

I'll post pics of it all later today.
 

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Alright, got some pics for y'all!

RH:


LH:


That's my little helper, 2-1/2 years old now. Took him and my 1 year old daughter to drags at Super Chevy the other weekend and both love it, especially my daughter. Both had hands raised in air yelling "Alright, Go, Go", and "Nova, Nova, Nova!" I love it. Wish I could of got it on video.

And here's my console and hand-brake setup I'm getting ready to start once the rear is finished:



 

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JohnnyRotten wrote:
that kid's gota dirty face !!! get 'im a samwich and some cookies... he's deserved it

lookin' good !!!
Yeah, he love's to help daddy, and get dirty too. Some day I'll actually be able to teach him what I'm doing, once I learn myself (lol), and get him involved. He already goes around all the time saying "Daddy, vroom, vroom, Nova!" :D :D

Speaking of the mounting, is it normal to mount behind the flange as I did? And there's only 3 bolts holding my brackets rather than using all 4.

I've seen other brackets (http://steeltechsolutions.com/REAR_DISC_PAGE_CODE.html) here that ProNova posted earlier that are solid with hole cut out to fit over tube, but fit on outside of flange. Just wondering if those are from different models or what?

Mine mounted fine, and I even installed one of the axles with rotor on it to make sure it all seated properly and it did, so I'm not worried about that I guess, just curious.
 

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well, ta be honest withya... i don't really care for aftermarket brackets. at least the ones i have. i bought a rear disc kit from a so called major distributor/manufacturer and they send ya these .010 shims ta use ta make the plates hang/install straight. i never had an issue with the stocker plates i used...as far as 3 bolts, i'd think it'd be ok, it's the same as the ones i have now (pretty much)

i bought a set of plates off e-bay that the guy sent me wrong (Seville instead of T/A) so i'm back ta square one on that... i was gonna swap my "kit" plates for the factory T/A plates... but looks like i'll be shimming the "kit" brackets instead.

i haven't really heard of anyone having issues with the plates, i'm just stating my own opinion and preferences...

oh by the way... ya know that with the e brakes in yer calipers ya HAVE to use the e brake ta keep the feed proper on yer pads. a big mistake made by some, not using e brake, brakes feed, wear, feed, wear... run outta feed... run outta brakes. ya gotsta run the e brake ta keep properly adjusted.



hope i helped in some way ;)
 

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Yeah, I read your ebay thread about the wrong brake setup. That sucks!

That's kind of what I was figuring as far as the e-brakes. They don't come with the kit I bought, had to pay an extra $100 for them and there ain't nothing to them, kind of pi$$ed me off about that, but you live and learn.

As far as I can tell with the e-brakes on mine, they just slide onto a pin on the back side of the caliper, sit on a hex shaped fitting and are held in place by a washer and nut. They originally came with a couple large washers used as spacers bolted on to it, I guess for a non e-brake setup. From what I can tell since I can't find the instructions, don't remember even getting any for that matter, the e-brake bracket just pivots when I pull the cable and puts tension on the pads. That sound right?

I was even considering welding the brackets to the flange for added security, but that would suck if I ever wanted to remove them or had to replace the rearend, at least since they are just bolted on I can ensure I'll be able to reuse the brackets if need be. I may even take one off before I get too far and finish it so I can make a template to make my own, then all I'll need is the calipers and rotors for my next project if I go with rear discs.
 

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jade76 said:
That sound right?

yes, and the spring that fits the lever to the bracket... the one the cable passes through is all ya need on yer e brake cable. the stocker cable should have about a 1/4" wound spring maybe 6" long (?) around the cable... this is the spring ya remove... ya don't need it... because of the other spring. don't scar or damage the cable removing this spring ;)

tomorrow i'll get a shot of my set up for comparison in addition to the Seville plates.


just so ya don't feel reamed on what ya paid fer yer plates... the T/A (got Seville) plates cost me $175. total... fer a screwin'
 

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just so ya don't feel reamed on what ya paid fer yer plates... the T/A (got Seville) plates cost me $175. total... fer a screwin'
Wow, I guess so! :eek: :eek:

There's actually two e-brake brackets for mine, and there isn't any other springs that came with it. One bracket has a hole through it to snap the cable in, which normally snapped into the drum plate, and the other which has a place to hook the cable ball? to actuate the brakes. Just by looking at the cable, I'm pretty sure I'm going to have to shorten it to make it work, and the spring makes sense. I was wondering how it's supposed to disengage when I release them, unless the hex fitting has an internal spring or something.

I'm also going to get some more pics, maybe I'm missing something (the spring), or they're different setups. It's hard to say without seeing them.

Thanks!!!
 
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