Hi,
I replaced the upper/lower control arms, ball joints, rubber bushings (and all body bushings) coil springs (front/rear both stock height), shocks, tie rods, center link and added a sway bar to front and rear. Wheel/tire combo is near stock at 15” wheels with an average tire size. I don’t have a reference to what the vehicle drove like before this work as it was not running when I got it years ago. Overall it rides great but I notice on certain rough streets, especially the older concrete roads here in some NJ towns, front end doesn’t absorb very well, rattles and sounds like a tank. Is this typical and if not what should I look at if all the components are new/replaced? I’m going to check the fender bolts to make sure all is tight but not sure what else to look for.

 

What are you running for tire pressure.

 

I’ll have to check once it’s out of the trans shop. They were nitrogen filled by the shop who I bought the wheel/tire set. For these Goodyear tires I believe the specs are 50psi.

 

That is likely the maximum pressure for maximum load. A lighter vehicle does not need as much air pressure as a heavier vehicle. The tires on my Jeep Wrangler say 55 psi max but if I run them at even 35 psi the ride is so rough it will rattle my fillings, so I run them at 28 psi. For the Cutlass, I run the BFG TAs at 32-35 psi.

 

Makes sense. I’ll check the pressure once I get the car back from the shop. If towards the max, I’ll drop it down and see.

 

Tire PSI simple check.
What brand of shocks are you running?

 

KYB front and rear

 

I had KYBs in my 68 and didn't love them(upfront). But it was the rebound I didn't like if I remember. Made the front end float.Could have been too harsh as well.

If tire PSI doesn't work try a different brand.

I'll have to look at mine to see what I settled on. I know the rears are Monroes and they are OK

 

Following up on this thread. After getting the car back from the trans shop, tire PSI was adjusted to 30psi for each tire. There is KYB shocks on front and rear with Moog springs all around. As stated earlier, all control arms and bushings along with body bushings were replaced, rubber not poly. I also did not switch to tubular arms and opted for the OE style. Overall the ride is good, it’s just some of the older roads and even smaller road issues seem to really feel it in the front. Maybe I’ll have to try a different shock and brand of tire. With 205/70 as current tires, would something else be better?

Would adding a coil over setup stiffen the ride even more and compound the rough ride problem?

 

Rattles and sounds like a tank. Sounds like loose or bad Sway Bar Link.

 

Thanks, I’ll look into those. I think Bilstein is probably a better fit for the GM platform than the KYB. I have KYB’s on my other modern cars and like them, just not so much on the Cutlass.

 

Thanks but sway bar and end links are new and properly installed.

 

Its ironic as I looked up those part numbers and they are ones I saw on RockAuto and wanted to get them. I wasn’t sure about the spring assisted rear absorbers and how they ride. Appreciate your input and I may give those a shot.

 

I am assuming you have 14" tires ??not sure if you had a typo , looks like the correct tire size should be 225-70-14
http://wheel-guide.com/makers/oldsmo...obile-Cutlass/

 

That site reference may be for factory but my wheels are aftermarket. 15x7 wheels with Goodyear 205/70-15’s. I may have to experiment with another size.

 

I have driven the current 1971 vert since 1990 and a 1970 Supreme hardtop since 1977 and I have not had any issues with the ride quality of either vehicle, with multiple different tire, wheel, and shock absorber combinations. In fact, I have always thought the ride quality was exceptional compared to other vehicles from this era with any setup my vehicle had at the time.

I guess I am not understanding what exactly is your complaint with the ride quality.

 

Thanks. They were a good option for my budget. I’m thinking of switching from the Goodyear 205-70-15 to a BF or Cooper 245-60-15. Maybe that and some different shock absorbers will balance it out a bit.

 

Not a complaint necessarily, just that I don’t have a reference point as this was a lawn ornament when I got it so it was never driven until after I put all the suspension components together. Overall it rides great but on some of the less than stellar NJ roads, I’ve noticed you can feel it in the front end. Now I’m not talking about hitting potholes but with all the salt and traffic, if the asphalt has some rough patches or bad road repairs, you can feel it. Perhaps it’s par for the course as I’m not expecting it to ride like a modern car but more making sure there’s nothing making my ride a bit rougher on the rougher roads or if this is just what is to be expected. Some have eluded I may not have the best tire size so I may change that to see. I’m also going to replace the KYB shocks for another brand.

 

Do you know anything about the springs in the car?

 

Yep. Both front and rears were replaced with new Moog springs when the rest of the suspension was replaced. Fronts are constant rate stock style springs for the 350 w AC platform.

 

Nice looking wheels
did the springs up front go into the upper and lower pocket correctly

 

Thanks, appreciate it. Yes the springs are installed correctly.

 

front end doesn’t absorb very well, rattles and sounds like a tank.

If you jack up the front end and double check everything. Ball joints, bearing, upper and lower control arms, etc.

You may need a buddy or two on rough road. To drive alongside front tires with head out the window. To see and hear what's wrong. If it warm outside.

 

If you end up contemplating a shock change, may want to review Koni Street (orange) - have them on my '72 and they're a great balance between handling and road absorption. Firm but not harsh. I'm originally from Philly so I know the road quality you're dealing with - these might be a great fit for you