Time for rear suspension redo... Advice needed!

[Trannyman95]

Hi Guys, the car is an 86 Cutlass with 8.5" rearend, Jegs adjustable upper arms that need new joints on the end (has rod ends on frame side), 85 GN replacement coils that are only a few years old but way too soft and the back sags, stock shocks, no sway bar, and everyones beloved SSM lift bars.

Last night I spent hours on here searching for rear suspension and while I did read a lot of great info it left me wondering what "I" need that will work best. I know there are a lot of great parts available now and despite what I have read my current setup hooks very good and I get zero tire spin on a MT drag radial street or track.... unless the track has water on it from the last guy dragging it up with him !!! With 3.73 rear gear I was cutting low 1.6 60's and the left front tire picked up just a hair watching my runs on videos.

After reading all of the issues with the SSM lift bars I really would like to take them off and go with something else because I do drive the car pretty often and like to go on long trips with it and the NOISE from the whole rear suspension drives me nuts going over bumps or pulling into a driveway! I never really liked the whole thin-sleeve nylon bushing idea since as mentioned it cannot swivel. I do think the bars are helping the car to hook but I dont like the side effects that I have been reading about. I just ordered the rear sway bar from Full Throttle Speed and a set of bags but now I am not sure what direction to go. I will likely use the bags as when we drive long trips to car shows or whatever all the extra weight in the back really makes the car sag and I had a lot of tire rub problems last year so if nothing else they will help prevent this.

My goals with the chassis/car??? This is a 100% street car that goes to the track now and then. I put 5-10K miles per year on this car. I would love to retain the traction I currently get but get rid of the side effects. I also want to make the car handle better and just installed 5658 springs in the front and have a 34 or 36mm camaro front sway bar and need to get the rearend in par with the front end.

For Wheels I am currently using the GTA wheels and dont have any clearance issues in the back. I have the rear GTAs on the front with a 1.25" which I am really up in the air on because they stick out a bit but are not past the fender lip, they just dont match how the front GTAs look on the rear and I put a 1/4" spacer to buy a little extra insurance against frame rub though there is good clearance. Tires are 245/50/16s all around and I will be using the MT ET Street Radials -Drag Radials - that are 255/50/16s on another set of rims for play on street and track use. My last set of rims were 15x8.5 and I was using the MT ET Street Radials that are 275/50/15s and stick like glue and again want to retain the same.

I am looking for some real world advice and opinions and am not looking to spend a fortune, just a reliable setup that works well all around that will get rid of the quirks I have now. I know everyone is going to have their own opinions and I respect that.... look what I am running now and am happy with other than the squeaks and noises lol! I dont need to hear "Those SSM bars are crap go throw them in the scrap pile!!!!!!" PLEASE!!!! I have read the other threads and know how most guys on here feel about them, I am not asking about them- I am asking what to REPLACE them with. I have also read of guys talking about upper relocation brackets for the upper arm. I see that Edelbrock offers something like this and really didnt see anything else out there but havent searched real hard either. I understand IC and chassis setup so I dont have a problem with guys offering advice in this department, but I dont want to build a race car rear suspension with infinate adjustment either because to be honest I will likely never adjust it once it is set up.

I appologize for the long post but wanted to provide as much info as I could and appreciate any advice/suggests/help that you guys can offer!!!

 

[KEVINS]

I don't know if the kits I offer are too Race Oriented for you but you can check them out here: Just Click on the "Malibu/G-Body" logo.

www.baselinesuspensions.com

Kevin

 

[jdpolzin]

What motor are you running? How does the front end sit? Im assuming you have a V8 and the car sits fairly low. The 5413's are a great match to the 5658's. As far as control arms go, you must have read my posts about the scrap pile! Yes good move on removing those things. It really depends how much you want to spend on the lower. I run Hotchkis lowers and I love them. These are basically them same as Metcos, either of these work great. As far as sqeeks go, a stock style rear bar may always give you moising while the chassis flexes, while pulling into the driveway for example. Really the best bar to get is the HR rear bar. I run an ATR right now and plan to replace it for this very same reason. Although the stock style bars do work great and have been tried and true for many years. I'm not a fan of any "relocating brackets" at all. These are just more problem points that may come loose and make noise, break, bend, or simply fall off. I would simply get a set of UMI double adjustable uppers. They're priced well and are good quality. This gives you the ability to adjust your pinion angle once its all together. No need to re-adjust after that. As far as aribags go, thats totally up to you and how wel the car launches. With an HR bar, most guys dont even need airbags but with a stock style bar, it might be a good idea to at least keep one in the passenger side. Good luck, if you need any help, feel free to send me a PM! --------Jeremy

 

[Trannyman95]

Thanks guys!

The engine in the car is a Series 2 3800 L67 supercharged engine like what is used in the 97+ GTPs and GS and I am running it with a 4L60E trans. I got the supercharged conversion done a little over two and a half years ago and its first track outing it ran a best of 12.21 at 108.5 with a 1.63 60' and has run lots of 1.65-1.69 60s on the MT drag radials. I bent the crap out of the stock driveshaft that day and at the time thought it was just poor wheel balance as the shop that put my tires on had a heck of a time getting them to balance! I have an aluminum shaft now that I had custom built so its smooth and I have had zero issues since. The rearend at time of 12.21 had 3.73s with an Auburn Pro series diff. The car currently has 3.23 gears as I was planning not only for a 650 mile road trip to a car show but also for if and when I go turbo as I am affraid that 3.42s just arent going to cut it into the mid 10s or faster ballpark if I ever get there but I have had very little time to work on this car until recently and I just want it done so I can enjoy driving it. I still pulled 1.70ish 60s with a converter that only foot brakes to 2300 which is the same converter that got me the 1.6s but keep in mind this engine has a roots blower that makes loads of instant torque and I always wanted to know what I could do with it in a car that I can go WOT from a stop and not spin! I now have a 3000 Vigilante in the car but have barely driven it and havent put drag radials back on yet as I just get a new engine together and am ironing out the tune on it.

As it sits now with the 5658 front springs from ground to center of front AND rear fender wheel I have 26 1/4" but again the rear springs are mush and are terrible with any amount of weight in the back seat or trunk so they need to be replaced and I wouldnt mind getting in the 26.5 or a little more range to put a slight bit of rake in the stance. The springs I just took out of the front were original 307 V8 springs that came in the car that had been cut about 1.5 coils and the front was pretty dropped and I measured the lip to the ground after I put one spring in to compare and it was 24 1/4"!!! YIKES!!! These GTA rims spaced out didnt agree and I couldnt hardly drive down the road so new springs were in order and you were one of the big influences on me going with these springs as you have helped numorous people with that advice and I love the road feel and height just as it comes out of the box and hope it will settle down a hair more over time.

 

[jdpolzin]

OK, well if you went with your 245/50R16's and the 5413's, your measurement to the center of the wheel well shoud be 26.5 to 26.75 depending on settling. The 255/50R16's are going to make the lip .25 taller. I really like the results of the 5413's and the feel of the springs for street/strip use with a good set of shocks. If the car was more of a drag car, I would think you benfit from a taller sping and a taller tire.

 

[Trannyman95]

I havent made any changes to the rear suspension yet as I am really im limbo on what to do- yes I have recieved a lot of great tips and help on the matter but there are a lot of choices to make!

Now..... I was thinking about this last night after me and the family went for a nice long cruise in the car and most of it was on bumpy roads and the rearend squeaks and rattles were driving me crazy lol .... DOES anyone make a lower control arm with a Rod-End on the front of the control arm and still utilize a rubber or poly type bushing on the back side? I really think this would be a good setup and compromise. It not only retains some cushion but also allows the rearend to move more freely without potential bind, or at least on the front end of the arm. I know there are lowers out there with a rod end on both sides, but how about something like the uppers that still utilize a bushing in the top of the rearend housing? If this sounds like a bad idea tell me now lol! If they exist I would really be interested in something like this, OR I am going to make my own and post up pics of this. Not that the lowers really need much adjustability but it would add a bit more adjustment to put the rearend where you want it.

As far as the uppers there are a lot of great ones out there too, but has anyone personally used the Edelbrock uppers?

Edelbrock 5247 - Edelbrock Adjustable Rear Upper Trailing Arms – SummitRacing.com

They look very nice for being adjustable while mounted and the enclosed front rod ends with grease fittings really seem like a plus as the Jegs uppers I have now have pretty beat and dead rod ends from the miles and weather that the car has been in since they have been on the car. I hate to keep pointed at Edelbrock for suspension parts as I know there are already options out there but they look like a very nice part and I am always one to try new things. If not the UMIs are probably the route I will go.

 

[charlief1]

I'm gonna keep up with your thread for sure. I saw your conversion and it looked like an interesting idea. Glad to see you got most of it worked out now.

 

[Trannyman95]

Well I guess the idea is already out there, Global West makes lower control arms that are what I was thinking would be an ideal balance....

1978-88 Chevell, Grand National, Cutlass, and Century rear tubular control arms.

Does anyone have any experience with these lower arms?