455man

72 Cutlass with a 455/TH400 w/stock convertor. I have a 3.73 10 bolt posi going in soon. I'm pushing about 400hp/500tq. 275/60/15 tires. I want to increase the traction for 1/4 mile runs or red light acceleration. I'll probably put sticky tires on it for the track but want better traction on the streets too. My first thought was to put all new rubber in upper and lower control arms and add a rear sway bar. I also thought about the factory "traction bar" only used on the 4 speed cars. But will this be enough or will I need some aftermarket upgrades? It's 95% a street car, driven 60% of the year. I like the soft ride it has now and dont want it to ride like a truck, but I realize I'll have to give up some comfort for performance. I'm also not looking to break the bank with this upgrade. I might try doing this myself. I'll be ok with a little wheel slip but dont want to spin the tires for a block. Anyone have a stock 442 suspension with a slightly modified motor that can chime in?

sicky olds

I was told that stiffer springs is a good way to get traction, something about the way it reacts when you hit the pedal.

455man

I've got old coil over shocks and I think someone put them on there because the springs were sagging. I'll probably put new shocks on it and probably new springs. I could go with the stiffer 442 springs.

droldsmorland

Poly graphite bushings, boxed lower control arms, 442 sway bar. Adjustable or upgraded HD uppers couldn't hurt either. Spring bags at least one in the passenger spring will help plant the tries. 25-2700 stall converter with that power rating.

455man

I've heard poly makes the ride really rough. Or is stiffening it up mandatory to get traction? Would the bags be a bad idea on the streets for daily driving? I drive this car to work when there is no chance of moisture. I plan on upgrading the stall when i put in a 200R4 tranny. That was the stall range I was thinking also.

70cutty

I just installed UMI Performance Rear control arm kit. It seems to be really good quality product for little over $300 from Summit.

sicky olds

Yes poly does make your ride more rough

RetroRanger

These are easy upgrades that can be completed in an afternoon I reccomend you try it yourself

New Moog rear springs 442 rate ~$75.

I used a parts place 1" rear sw bar and boxed lower arms w poly ~$300.

replaced upper CAs bushings w Moog parts ~$30

then your choice of shocks, for under $100 you could get KYB gas a justs shocks or pick something you like.

so for about $500 you could completely upgrade the rear suspensiion to meet most of your needs....some of your traction issues may be related to the coil overs and sacked stock springs...

455man

Thanks Retro and 70cutty. I'll look into these. I'm sure my current suspension is not set up right but didnt want to upgrade it and then find out it rides way too rough or still burns the tires off.

tmaleck

Mine is a 67, but I did the tubular upper and lower arms with poly except the uppers on the diff ears, kept those rubber. Rides firm but not bone jarring.
Tim

455man

Anyone have a big block with a posi that can comment on traction with these mods?

'69CutlassVert'

Agree with poly issues on ride. I went with Moog 442 spec front springs and for ride sake, on the rear I went with progressive overloads. Rides good for daily driving but when the rear drops under red light acceleration they stiffin up quick and dig in. Went with gas shocks all around. You're going bigger and faster than I plan to. Just a thought on rear springs if to want to save the ride some.

Run to Rund

Keep the rear low to improve the geometry of the control arms. All I have (stick car) is hard rubber bushings, fairly stiff coils, sway bar.

1964f-85

I have poly bushings, factory boxed lower and stock upper which i boxed myself, stock 442 springs and gas shocks, station wagon sway bar.

It sits with the lower control arm level to the ground, the front is lowered 2".

I have a masies 9" ford with protrax posi unit.

When i stand on it, the rear lifts slightly and the car spins the tires like crazy. No wheel hop and a soft ride.

ziff396

I have boxed lowers with poly bushings, 1" sway bar, UMI uppers with roto joint, factory "traction bars", and edelbrock shocks. 3.42 posi rear. New 442 spec springs. The UMI uppers really made a difference in the ride after installing them. They take out the geometry problem with the originals binding when compressed.(bumps etc). No bounce. I am running BFG 275/60/15's. It still just almost stands still and just smokes the tires if you hammer it. 1 block? I can't get 30' before I hit 3rd! I may have more torque than you but it still plays in to learning the car and playing with the gas at launch until you obtain traction. Better tires and bags would help mine also, but I just drive street. Oh and I have no wheel hop.

Olds442redberet

I know this is an old thread but I used this thread and a few others like it to help me decide on the components to use on my rear suspension rebuild. So I figured what better place to talk about the end results.

And, A big thank you to everyone for your input. It helped out Tremendously.

Olds442redberet

Before starting on this project my suspension was pretty ragged out. Knowing how expensive these projects can be I am breaking down the suspension rebuild into two sections with some minor things being tweeked as things progress.

I started my project by conducting research, mostly here on this site. I read quite a few threads and took in a lot of information before actually buying any parts. I even wrote down the part numbers for the parts I wanted from one of the many threads I read. No since in reinventing the wheel...right?

I went with stock 442 springs from Moog, boxed stock trailing arms, a large one inch rear sway bar and a pair of Bilstein shocks.

This afternoon I actually put everything on the car and the results were tremendous. Wow! What a difference in the ride. And I havn't even touched the front end yet.

Olds442redberet

As you can see, my shocks and springs were shot.

One of the issues I ran into while putting the shocks on was the exhaust ran too close to the shocks. So I had to cut the pipes right behind the Magnaflows. I'll take the car over to the exhaust shop and see if they can put it back in correctly. The real shame is the exhaust is new. Oh well.

I'll get the upper trailing arm bushings addressed later in the week after I get a set of bushings installed in a set I have sitting on the shelf.

I am going with rubber bushings in order to keep that comfortable stock ride.

70convert

Which supplier did you did you end up buying these from.
Thanks

Olds442redberet

I bought the springs from Jegs via Ebay $68.00 Free Shipping
The sway bar came from Tamraz Part, again via Ebay $157.00 Free Shipping
The shocks came from SouthWestSpeed.com via Ebay $160.00 Free Shipping
The trailing Arms came from Columbia Parts via Ebay $163.00 Free Shipping

Total $548.00

Moog Spring insulators were already on the shelf from a previous build Approx $15.00
Upper trailing arms (still need new bushings) Approx $30.00 at Advance Auto
Fix exhaust so the pipes clear well away from the shocks (unknown)

455man

Thanks for sharing. I haven't tackled my project yet. I'm hoping to this fall. I'll assume the ride is stiffer but not too stiff? The curvy roads are probably awesome.

Olds442redberet

The ride feels stock until you do something radical like a sudden lane change or spin the tires. The tires do plant better now than before the upgrades. Much, much better!

455man

That's good to hear.

rjohnson442

I always thought you want softer springs for more traction. The weight then sits down on launch over the wheels and applies more pressure(traction) to the ground. any insight on this?

Olds442redberet

I always thought firmer springs transfered the energy better. Softer springs would absorb energy as they compress.

Fun71

You DO NOT want the rear to squat under acceleration. Squatting means the upper and lower control arms are moving towards each other, compressing the spring which reduces the downward force on the tires. Think about drag racers who put air bags in the springs to stiffen the suspension and prevent spring compression. They wouldn't do this if they wanted the rear to squat.

JohnnyBs68S

Since the OP was wanting better traction, I'm surprized no one has suggested "lift bars" like the SSMs (Jegs now makes the equivalent thing) that relocates the attachement point of the LCA at the axle a few inches lower. This moves the instant center of the rear suspension towards the rear of the car, which has the effect of shortening the lever arm through which the axle's reaction torque works to increase downward force on the rear axle under hard acceleration.

When I rebuilt my rear axle a few years ago, I used SSM (South Side Machine) lift bars to replace my (non-boxed) LCAs, and used Edlebrock adjustable UCAs to be sure I could dial in my pinion angle. All these came w/ poly bushings for durability. While I have yet to upgrade shocks or springs from factory specs, I do have a 442 rear sway bar and also added the frame braces (the "traction bars" mentioned that came on 4-spd cars that tie the forward UCA mount to the forward LCA mount). I used tubular aftermarket braces (can't remember the manufacturer, but they were beefier than the factory "L" brackets).

Regarding the harshness of poly bushings, my opinion is that ride harsness is more a function of spring rates and shocks than whether or not you are running poly or rubber bushings. Polys do transmit more high frequency noise from the road to the chassis, so they are a little louder than rubber bushings (in addition to being prone to squeeks, especially when cold). But I would not consider their effect on the "ride" as being harsh.

Olds442redberet

I am just bumping this thread for a fellow member who asked for some information. Sorry

wheels442

I am just starting to research what I am going to as far as rear upgrades on my car. This is great info. Does anybody else have input on the "lift-bars" (i'm not sure how this works)? And has anybody here done these mods AND air bags? I am planning on over 500 ft-lbs of torque and I really want to be able to achieve traction...not boil tires while looking at taillights!!

sbceater

Hey johnnybs

also added the frame braces (the "traction bars" mentioned that came on 4-spd cars that tie the forward UCA mount to the forward LCA mount).

what are these "traction bars" your talking about?