68 nova suspension ideas

[Emmett17]

Hi guys, I’m new to the forum and am just getting around to planning out my nova build. The car is a 68 Chevy ll nova. Plain Jane, in-line 6, three on the tree. My goal for the car is a sbc backed with either a 5 or 6 speed trans. I’d like to be able to street drive this as well as attend local auto cross events, with a bit of spirited driving on back roads. I’ve been looking and reading up on suspension set ups guys have been using. I’m curious as to what everyone else is doing when it comes to keeping the stock sub frame. Has anyone ran tubular upper and lower control arms with the gmod? I’ve read some guys use global west control arms while bringing the bolt hole only down (as opposed to down and back). I guess I’m just looking for effective combinations guys have been running on stock sub frames. Ideas and suggestions are more than welcome! Thanks!

[TheBandit]

I am using a stock sub frame suspension on my '70 Nova and I've made upgrades over time which has softened the financial impact while I continue to have fun with the car and discover major improvements incrementally. The way you described using your car is exactly how I use mine: mostly street, some autocross and some backroad driving. The stock-based suspension has it's limitations, but it has never stopped me from having a great time with my car or being as competitive as my driving skill (or lack thereof) will take me. Some people get really caught up in doing everything all at once, but that can keep the car down for long periods of time; these days I prefer to keep my car running and take on smaller projects even if it's less efficient than doing everything at once. Keeping stock based suspension allows you do things over time and also take advantage of used parts that do come up periodically. You wont end up in as good of a place as if you go all out up front with aftermarket suspension and major mods, but you can get on the road and take your time with upgrades. It suits my needs and budget well.

First thing's first, I started by getting my feet wet with entirely stock everything. I went to my first autocross event and I clapped out the car with a true "run what you brung" mentality. In my opinion, everyone should start here. This is how you will identify priorities for your car and you as an individual. You might find you hate your seats or you hate the body roll or you hate brakes etc. For me, I did not like how my car felt like a slinky. It felt like the car couldn't keep it's feet under it because there was so much body roll.

https://static1.pt-content.com/images/pt/2020/04/ly6swap5JPG-1.jpg

Right about this time my old small block took a dump and I started doing an LS engine swap. While I was swapping my engine, I took opportunity to do the Gouldstrand mod since I had good access to the frame. I also addressed body roll by installing a larger sway bar, stiffer springs, and better shocks in the front. I found some lightly used tubular upper arms, which allow for increased caster. Then I took the same car out and drove the pants off it again.

https://static1.pt-content.com/images/pt/2020/04/ly6swap1003-1.jpg

Here is a video driving the car in that configuration link (https://youtu.be/DQUMTftKcS8)

I learned a number of things from that first around of suspension upgrades. The additional roll stiffness up front helped with body roll, but with the tail end mismatched the car was really unbalanced. The back end continued to roll like a slinky and the front was stiff by comparison. It was impossible to know how much the additional camber gain (from g-mod) or caster (from tubular upper arm) affected things because the unbalance dominated everything and the tires were a major limiting factor. If I remember correctly, I pulled a best case 0.6g in a corner with this combination.

What would I do differently? Instead of doing springs, shocks and swaybar up front only, I would do front and rear simultaneously. If money was a limitation, I would do springs and shocks first. I would save the other changes I made for later because I don't think the old tires on 15" wheels could really benefit as much from the gmod or additional caster afforded by the tubular upper arms. In retrospect, my priorities would be springs & shocks all around, then tires.

Never-the-less, I persisted. Recognizing the imbalance in my car, I set out to get stiffer leaf springs and shocks in the back to go better with the front. Because I wanted lowering springs, I found I also needed to change wheels (to fit properly out back), so I made a series of changes simultaneously. I swapped the rear leafs, rear shocks, added a rear sway bar, and installed 18" wheels with modern low tredwear tires. While I was doing work in the back, I also replaced the drums with LS1 rear discs. Snowball! I didn't get out to autocross for a while, so I also managed a few other upgrades to the car. I swapped in some high bolster bucket seats to better hold me into the car.

The next time I went out, the car was a completely different animal.

https://static1.pt-content.com/images/pt/2020/04/ly6swap1348-1.jpg

Here is a video driving with that new configuration link (https://youtu.be/nwHwIcFJUTU)

That autocross trip was the first time I recorded >1 lateral g. The biggest difference was in the tires. The modern low tredwear tires made a HUGE difference. The car went from having a very unpredictable threshold to a point where I could feel the threshold of traction and ride that threshold around the corners. The car also achieved really important balance. This is why I said above if I was doing everything over again I would start with springs, shocks and tires/wheels; that's where I think you will get the most bang for your buck. Then I would move on to sway bars and geometry improvements.

I have been on other trips since then with very little changing on the car. What I've found is that at a certain point, the DRIVER is the best place to make upgrades. The best way to do that is through seeking coaching, reading, and best of all gaining experience. For the most part upgrading yourself is cheap.

Today I'm continuing to make upgrades to my car. I have upgraded my brakes to C6 variety up front instead of the original single piston discs. In my opinion, when my original disc/drum brakes were in good repair, they functioned and performed very similarly to my now-new brakes. I was having issues with one of my calipers up front, so I decided to upgrade. I would prioritize brakes only if your current system isn't up to snuff. My next upgrade for the car will be a faster and heavier steering box, because the original box provides very little feedback.

I hope sharing my experience helps you think through this. There is a lot that can be done and it can be overwhelming, especially on time and finances. Let me know if you want any more info or thoughts. There is no right answer here - only what's best for you.

[mbheinz]

I have a 70 Nova with the stock subframe that I use for street and autocross too. After installing no name drop spindles the car rode so bad I wound up installing a complete Ridetech front and rear coil over system with Truturn and Musclebar. After that the car rode and handled so good that I started to autocross. Did a few events on old high tread wear tires to get my feet wet. I agree with Bandit that autocross specific tires are HUGE no matter which way you go suspension wise. Squeeze the largest tires you can on the car then start upgrading as you see the need. Here is a pic of my car at Goodguys Scottsdale.

https://static1.pt-content.com/images/pt/2020/04/79965780_2474550969339794_47466253567676-1.jpg

[Emmett17]

TheBandit,

thanks for taking the time to reply with such detail. Your nova looks amazing! I really enjoyed reading about how you went about improving your ride a bit at a time. I’m itching to get mine on the road before fall! I think I’ll take your advice and go for the springs, shocks, sway bar and tires first, then run the snot out of it. How much did you drop the front and rear? I’ve been looking at the Hotchkis rear lowering leafs, they seem to fit what I’m looking for. Did you by any chance use drop spindles? I’m trying to stay away from those as I feel keeping the travel of the suspension is more important. I’m finding people either love them or hate them. I’m probably going to run tubular uppers and lowers but there’s far too many options out there to know what ones to run. As for the coaching, reading and gaining experience, I feel that is probably the best thing to learn. Besides it’s free, as you said. I’ll probably be asking you a bunch of questions once I start this adventure.

[Emmett17]

mbheinz,

How large of a tire are you running? I not looking to cut up the back end to mini tub it if I can help it! My nova has a bit of body work to look as clean as yours does!

[TheBandit]

thanks for taking the time to reply with such detail. Your nova looks amazing! I really enjoyed reading about how you went about improving your ride a bit at a time. I’m itching to get mine on the road before fall! I think I’ll take your advice and go for the springs, shocks, sway bar and tires first, then run the snot out of it. How much did you drop the front and rear? I’ve been looking at the Hotchkis rear lowering leafs, they seem to fit what I’m looking for. Did you by any chance use drop spindles? I’m trying to stay away from those as I feel keeping the travel of the suspension is more important. I’m finding people either love them or hate them. I’m probably going to run tubular uppers and lowers but there’s far too many options out there to know what ones to run. As for the coaching, reading and gaining experience, I feel that is probably the best thing to learn. Besides it’s free, as you said. I’ll probably be asking you a bunch of questions once I start this adventure.

Thank you Emmett. I think it's worth noting there are many great products and manufacturers to choose from for these cars! Up front I am using AFCO 600lb/in springs with AFCO spring adjusters modified to fit the spring bucket in the frame. I adjusted them to the same free length as Hotchkis 2" lowering springs for this application and since they have the same rate, the Hotchkis springs should give the same or at least very similar results. At the time I wasn't sure what ride height I would want to end up with thus the adjusters, but I haven't felt a need to adjust from where it's sitting. I am using stock original spindles, no drop. The body mounts are solid but stock height. Out back, I haveHotchkis 1.5" lowering leaf springs. The car has a very slight rake to it but I like how it sits.

Regarding control arms, the main advantage of replacing the upper arms is being able to run more caster. Make sure whatever arms you buy have enabled that. I am using Global West uppers and they have the balljoint positioned slightly back to allow more caster. I believe that's true also for DSE, Speed Tech, and a few other arms, but some manufactures don't include this change. There's really no advantage over stock arms otherwise. For lowers the main advantages of tubular arms is that they are new and stronger design, therefore less likely to fail near the outer balljoint. Also if you are going to coil overs, tubular arms designed for coilover mounts are the way to go. Right now I am still running the stock lower control arms and I do fear they may fail near the lower balljoint given how hard I drive the car. I am considering swapping them for tubular arms for peace of mind.

[2yellow69]

Great info Clint! I enjoyed reading your progression through the suspension maze.

Emmett,
I just found out that the Nova I am finishing for our daughter has lowering spindles. I am waiting on stock replacements to arrive. I have no idea how the car would have driven with them but my guess is pretty bad. The steering arm/balljoint interferes with the tire and wheel. To avoid that they "engineered" a higher mounting point for the steering arm which destroys the relationship of the tie rod and lower arm causing massive bumpsteer. My daughter and I installed the sway bar and found the steering arm interfered with the end links. It's not possible to steer the car!!

[mbheinz]

mbheinz,

How large of a tire are you running? I not looking to cut up the back end to mini tub it if I can help it! My nova has a bit of body work to look as clean as yours does!

Thanks Emmett! I'm running a 315 30 18 in the back and it's minitubbed. I was running 255 wides in the front but they had a very slight rub on the frame behind the wheel, the front of the upper control arm, the Musclebar and the outside of the inner fenders. I autocrossed that way for a couple of years and felt that was all I could squeeze in there. After speaking to a couple of local and out of town racers I decided to make a change over the holidays. I switched to 275's in the front. Still the stock subframe but I had to notch the frame, clearance the inner fender, redesign the upper control arm and swapped sway bars to a nascar style splined bar. I'm actually running a donated bar from an old Winston West stock car right now. With the wider tires the car feels more neutral now and I'm looking forward to racing again someday!

I have gone through everything The Bandit has in almost the same order and his write up is spot on. Work on your driving and make changes to the car as you improve. Most importantly, have fun!

[409novaman]

[QUOTE=TheBandit;1326780]
https://static1.pt-content.com/images/pt/2020/04/ly6swap1348-1.jpg

Just a quick question from a fellow Nova owner. In this picture could you tell me front and rear wheel and tire sizes. Also backspace measurements of the wheels. I'm just trying to get in the ballpark on my own car. Thanks for any help!

[F-Body International]

I know this thread is a ways into suspension talk at this point but I just want to get one simple thing out there before you dive deep into suspension modifications...

Get your frame locked to the body with solid body mounts! If you haven’t done this, this is the first thing you should do before anything else. Eliminating flex between the body and subframe forces your suspension (stock or aftermarket) to work in its intended design. This is one of the best upgrades you can do for your money.

A cool thing with solid body mounts is the option to lower the front of your car 1/2”. The suppliers that make solid body mounts offer “standard” and “1/2” drop” body mounts.

Global West, DSE and others make solid mounts for these cars. I wouldn’t think too hard about who you go with for that but, again, I would start there.
DSE...
https://www.detroitspeed.com/body-8/detroit-speed-inc-body-mounts-1967-69-camaro-firebird-1968-74-nova-1970-81-camaro-firebird-010301-group
1/2” drop version from Global West...
https://www.globalwest.net/801.html

[F-Body International]

2nd piece of advice, like TheBandit said, don’t let this project snowball. It’s easy to do that (I have myself). I don’t know what your budget is but for most people right now, bang for the buck is most people’s budget.

After the solid body mounts, shocks and springs would be next on my list (like TheBandit says).

Most people shy away from 15” wheels but you can really do well for your money with a 15” road race/autocross tires. BFG and Hoosier have some 15” choices. For your money, staying with stock style D52 brake calipers is another thing I would consider. Most people jump away from stock brakes but there are so many street and even race pad choices.

[TheBandit]

Just a quick question from a fellow Nova owner. In this picture could you tell me front and rear wheel and tire sizes. Also backspace measurements of the wheels. I'm just trying to get in the ballpark on my own car. Thanks for any help!

The story behind that is complicated. I converted my 12bolt rear to Ford bearing ends and narrowed the rear axle 1" per side. That allowed me to eliminate the c-clips and use more widely-available 1pc cast wheels in the style I wanted. At the time, 1pc cast wheels in 18" didn't seem to come in Nova-friendly offsets. Alternatively I could have purchased 2pc or 3pc wheels and had the right offset built into them - that would be a lot easier! However, I enjoy doing things the hard way some times, because I like to learn and try new things. From a cost perspective, the cost savings for 1pc wheels instead of 2pc wheels offset the costs of narrowing the axle myself, including new axles, bearings, housing ends, seals, etc. Plus I was able to eliminate the sloppy c-clips. I think most people should just buy the right offset wheels or compromise with narrower wheels and tires if they can't get/afford the offset they want. All that said, my wheels are 18x8 4.5"bs and 18x9 5"bs Rev 107 wheels. The equivalent for a non-narrowed rear axle would be 18x9 6"bs.

[409novaman]

The story behind that is complicated. Thank you.

[Emmett17]

Thank you guys for all the thoughtful and very helpful advice. I think the best route for me to go is exactly as TheBandit described, a little bit at a time. I’ll probably upgrade the brakes with one of Baers kits. I’ve been planning on running 17s because of that, though I’m not sure about the back spacing or tire size on them to fit properly. I agree that spring, shocks, decent sway bars and tires can take me a long ways as the car is. That should be plenty of work to keep me busy and still have time to enjoy it this summer and fall! It didn’t think of crossing my mind about the solid body mounts and how they would help the suspension work and function as it should. I’m very much looking forward to starting this project and seeing how both myself and the car perform. I’ll have to start a post about the project as I start tearing into it. Thank you all for the helpful pointers and info. The more I read here and ask questions, the more I’ve been learning. Any advice on welding the stitch welds on the sub frame?

[2yellow69]

F-Body mentioned 1/2 height solid subframe bushings. While I agree with solid body bushings I would recommend you not use 1/2 height bushings. I tried them with my 69 Camaro and it threw everything off a little. The steering column to steering box angle was a little stressed and lining the front fenders up to the doors was enough of a problem that I bought full height bushings. I just didn't have the patience to deal with them! I did stitch weld the frame about every 6 inches.

[Emmett17]

I’ll more than likely run standard height bushings after reading that. Any thoughts on coil overs in the front compared to lowering springs with decent shocks, besides adjustability?

[2yellow69]

I am definitely not the voice of reason when it comes to that choice. I have coilovers, but I let my Camaro turn into an avalanche which has kept it off the road for years. It's very close to being done. I will have it going as soon as my daughters Nova is done. TheBandit did his build a little at a time which kept his car on the road. F-Body is 100% correct in saying bang for the buck is the way to go.
174637

[Emmett17]

That looks like a really nice set up. I love how nice things look when they are clean and put together! I think that’s honestly one of the most satisfying things, seeing everything come together and function how you’d like. What are you running for coil overs? Also those of you that have a garage, I’m a bit envious. Working on your back in the driveway like a dog tends to get old at times.

[2yellow69]

Thanks. The setup in the picture is my old stuff that I just put into my daughters Nova. Global West upper and lower control arms, Speedtech Chicane coilover mount, Chris Alston Varishock coilovers, Eibach springs and Hotchkiss swaybar. The picture shows ATS tall AFX spindles and Corvette C5 brakes which are staying with my car. Her car already had new Wilwoods when we bought it and Belltech drop spindles which don't fit well. Tomorrow I am going to show her how to put stock spindles on.

[F-Body International]

Listen to the last statement about drop spindles not fitting well. This is true so I would try to stay away from them. The steering arm starts getting in the way of wheels/tires.

[Pro Touring Store]

RideTech would be my first choice; followed by UMI.

[79T/Aman]

supporting the forum you advertise on would be nice ;-)

[Emmett17]

F body international,

I’m planning to stay away from drop spindles and going with standard disk brake spindles instead. I’ve heard too many negative things about the drop spindles.

[Kenova]

I bought my Nova as a roller. Sorry to say, it also snowballed. Everything that was attached to the body was removed and cleaned up.

About the subframe. Clean it thoroughly before welding up all of those booger welds and move around a lot as you do. It is beyond me how these things held together.
I did the Guldstrand Mod while it was out of the car. Do it the same way Clint did it if you can. It gave me about 5 degrees of caster.
It was then re-installed with DSE half height solid bushings. Don't forget about the extra half inch spacers at the firewall.
Loosen all attachment points for your steering column before you install the subframe. This will prevent any binding.

I also ditched the slip-n-slide bench seat and installed some buckets with lateral support and new three point seat belts from Morris Safety.
Other than a T56 swap this is as far as I have gotten. It makes for a nice cruiser but I would have reservations about throwing it around on a autocross course. If I had read a post like Clint's before I started I think I would be much further along.
After I spend some time and money on my Vega I will turn my attention to the suspension on the Nova.
To mini tub or not, that is the question.

Ken

[2yellow69]

A big thanks to Kenova for mentioning the spacers at the number 2 body mount. The car we are working on (74 Nova that looks like a 72) did not have these spacers. I thought it was interesting that the 4 main body mounts looked almost new and the radiator support bushings were completely trashed. The whole time I've been working on the front of this car I knew there was something I was trying to remember!! A long time ago I read about the Novas having that spacer. Since I have been working on my 69 Camaro for the last decade I never thought about it. Sure enough, I just went to the garage and looked under the car. The subframe is angled up from rear to front. I looked in the factory 72 Nova assembly manual and those spacers are the last part listed for assembling the subframe to the body. Part # 3920260 (1/2" thick). Even though they are listed for 68-72, I can say that looking at my daughters 74 convinces me that the 73-74's need it also. I will also have to buy longer bolts as the Global West supplied bolts will now be short ( I bought this solid bushing kit at least 10 years ago so that might have changed).

[Kenova]

I too reassembled my Nova without the spacers, so you're not alone.
I thought the sub frame was bent. Couldn't for the life of me get the sheet metal aligned once the sub was in. Then someone on PT.com mentioned the spacers :hand:
The originals had been thrown out so I made a pair from some scrap aluminum. All is good now LOL.

Sorry for the thread highjack Emmett.

Ken

[TheBandit]

Any advice on welding the stitch welds on the sub frame?

I would consider rewelding to be a cosmetic endeavor.

The factory welds are not pretty, but I also haven't heard of them failing. There is a lot of weld length around critical areas like the control arm mounting locations, crossmembers, body mounts, etc. The "rail" sections of the frame are formed in an overlapping "C" box shape that is fairly strong on its own, regardless of the stitch welds that tie it together.

On my frame, I cleaned up the factory weld spatter years ago, but I have not redone any of the factory welds beyond what was necessary to do the Gouldstrand mod the "hard way" and in sections I notched for low-mount LS engine accessory clearance.


I too reassembled my Nova without the spacers, so you're not alone.
I thought the sub frame was bent. Couldn't for the life of me get the sheet metal aligned once the sub was in.

Guilty here as well! I unnecessarily pounded a huge dent into my firewall for distributor clearance and drove my car for 10 years with a huge gap at the bottom of the fender because I had no idea those spacers were needed. I corrected the issue a few years ago by cutting new spacers from 1/2" aluminum via a hole saw. I wish companies selling bushings for '67-69 Camaro / '68-'74 Nova would put a warning in their instructions!

[2yellow69]

I know we side stepped the original reason of this thread but I have one more thing I found out that I would like to share concerning those bushings. 67-69 Camaros don't need the extra 1/2" spacers. 68-72 Novas came with 1/2" spacers from the factory. After hours of reading on the never-ending internet, I found out that GM engineers changed the bushing itself for 73-74 Novas. They got rid of the separate space and made the bushing 1/2" taller. That is why there were no spacers on my daughters car. Classic Industries sells the correct height bushings for 73-74 in rubber.

Clint is correct that companies that make these solid mounts need to have better instructions with them.

[Emmett17]

No worries about the hijacking! I’m soaking all this up. So many things that never crossed my mind, such as the spacers.

[Binford 6100]

I would consider rewelding to be a cosmetic endeavor.

The factory welds are not pretty, but I also haven't heard of them failing. There is a lot of weld length around critical areas like the control arm mounting locations, crossmembers, body mounts, etc. The "rail" sections of the frame are formed in an overlapping "C" box shape that is fairly strong on its own, regardless of the stitch welds that tie it together.

On my frame, I cleaned up the factory weld spatter years ago, but I have not redone any of the factory welds beyond what was necessary to do the Gouldstrand mod the "hard way" and in sections I notched for low-mount LS engine accessory clearance.



Guilty here as well! I unnecessarily pounded a huge dent into my firewall for distributor clearance and drove my car for 10 years with a huge gap at the bottom of the fender because I had no idea those spacers were needed. I corrected the issue a few years ago by cutting new spacers from 1/2" aluminum via a hole saw. I wish companies selling bushings for '67-69 Camaro / '68-'74 Nova would put a warning in their instructions!

Have to disagree with you about rewelding the factory seams.
I am a certified welding inspector by trade and have seen the welds on the factory gm frames.
While the may hold, their is alot to be desired from the factory welds. There is alot of strength to be had from a properly welded frame.
Worth the time in my opinion.
Sure they might not break from the factory but add a bunch of aftermarket parts and start tossing the car around the autocross or track and the forces and stress are going to more then that chassis ever has seen before.

100% worth the time and money to reweld your frame/subframe.

[TheBandit]

I stand corrected and I'll defer to the subject matter expert.

Following the post above, I did some digging and found one example described here: https://www.chevydiy.com/how-to-restore-your-chevy-camaro-front-suspension-guide/. This related to the control arm mounting area, and not the stitch welds along the top rails of the frame that go under the car.


The upper control arm tower and shock mount get a lot of abuse and they don’t get a lot of attention. The shock plate can be cracked where it meets the frame rail and can go undetected because it’s covered by the control arm. Hairline fractures commonly start around factory welds at the base of the control arm tower.

https://static1.pt-content.com/images/pt/2020/04/130-1.jpg

Another area of concern, unrelated to welding, is where the sway bar mounts to the frame. There's an example of that described here: https://www.camaros.net/forums/16-brakes-suspension-steering/193392-frame-cracked-big-sway-bar.html



I use this car for my daily driver and have driven it 115,000 miles with this 1 1/4 " sway bar on it. Also found the sway bar frame mount bolt loose, the nut had disappeared.

This car is driven gently. So you guys autocrossing your car need to keep this in your check list when inspecting your car.

https://static1.pt-content.com/images/pt/2020/04/camaroswaybar002-1.jpg