85 LX Rough Ride

[83Softtop]

I just added an 85 LX 3.8 C-5 to the family, still have the 83.

It is a good solid stock car, very nice, but is surprisingly rough in the front suspension over small short bumps like speedbumps or tree root bumps in asphalt. The original owner said that the salesman mentioned the car had the "sport suspension", but I can't find a reference. It is NOT a 5.0, so I'm not sure there is such a thing, but the front stabilizer bar is 1 1/4", whch is huge. My 83 5.0 is only 1". Does anybody know what I have, or how to find out.

I know the Fox front suspension is a very good performer so, at 152,000miles I'm suspecting the struts need replacement, they may have lost any gas charge they had. I will replace the generic tires with top line touring radials plus wheels, I'm thinking Michelin.

Any ideas or comments would be greatly appreciated.

 

[2000xp8]

Add energy suspension isolators all the way around. They take all the thump out of bumps. You would be amazed that how much better $50 worth of isolators will improve ride quality.
Just expect about 1/4 inch more of a ride height.

The previous owner of your car may have removed all the stock rubber isolators (which get flat anyway). I know from personal experience that removing them is a bad bad idea.

 

[stang&2Birds]

A few questions:
What rims and tires (exact make and model!) are on the car?

Then, spend $1.00 and get a tire pressure gauge. Make sure all of the tires are at the correct pressure ~28-35 (as long as they are all similar). Hey, don't laugh, I'd say that most of the yahoos that post BS specs on their car's ride height haven't check their tire pressure in over 6 months.

Now:
A) Find a level and flat surface.

B) Measure all four corners from the ground to the center of the fender lip. If you're like many people, and like me, you'll find that it's easier if you use a level to make sure that the tape measure is perpendicular.

Post the results of the measurements.

BTW: No, you will not have any two measurements the same (within 0.1"). If you do, then you suck at measuring. But, to the ~1/8" is good for our needs now.


FYI:
Mustang 86 - Mach1 Springs

Four Eyes Rule!

 

[83Softtop]

I got the measurements

A few questions:
What rims and tires (exact make and model!) are on the car?

Then, spend $1.00 and get a tire pressure gauge. Make sure all of the tires are at the correct pressure ~28-35 (as long as they are all similar). Hey, don't laugh, I'd say that most of the yahoos that post BS specs on their car's ride height haven't check their tire pressure in over 6 months.

Now:
A) Find a level and flat surface.

B) Measure all four corners from the ground to the center of the fender lip. If you're like many people, and like me, you'll find that it's easier if you use a level to make sure that the tape measure is perpendicular.

Post the results of the measurements.

BTW: No, you will not have any two measurements the same (within 0.1"). If you do, then you suck at measuring. But, to the ~1/8" is good for our needs now.


FYI:
Mustang 86 - Mach1 Springs

Four Eyes Rule!

It has 14"x6" stock Ford steel wheels. Front tires are KUMHO Star Power 758 205/70R14 95T M+S (China junk) both at 33 PSI. Rears are WYNSTAR Phaser R23 205/70R14 95T M+S (also China junk) both at 31 PSI.

All four are reasonably round with no lumps or bumps.

Took a while to find a very level spot I wasn't run out of right away.
Measurements warm, no passengers or load, as follows: LF=26 1/4"..RF=26 1/16"
LR=26 3/4"...RR=26 3/4". Apparently I can't measure because the rears WERE the same.

I also visually inspected all the rubber bushings and stabilizer mounts, and all look satisfactory for the mileage. The struts are original Ford.

I am beginning to suspect tires AND struts, (the roughness is only when the front wheel(s) hit bumps, not the rears). I will have to go to 15" or 16" wheels to properly upgrade the tires, and I was thinking KYB struts and shocks for the daily driver this car is.

Suggestions would be appreciated, thanks, 83Softtop

 

[stang&2Birds]

It has 14"x6" stock Ford steel wheels. Front tires are KUMHO Star Power 758 205/70R14 95T M+S (China junk) both at 33 PSI. Rears are WYNSTAR Phaser R23 205/70R14 95T M+S (also China junk) both at 31 PSI.

All four are reasonably round with no lumps or bumps.

Took a while to find a very level spot I wasn't run out of right away.
Measurements warm, no passengers or load, as follows: LF=26 1/4"..RF=26 1/16"
LR=26 3/4"...RR=26 3/4". Apparently I can't measure because the rears WERE the same.

You have lowered springs on the car. The fenders of Stangs should sit ~27" to ~27-1/4" from the ground.

Chances are that you have what *I* call "ricer" springs. Specifically, springs that are too soft for the drop! I'd say that ~90% of the Stangs are lowered that way.

For a fender height of ~26", you should have a spring rate of ~800lbs/in or greater. That's very close to a pure autoX/circle-track spring rate. It's VERY stiff.

Chances are you have either a stock ~530 rate, or an ~600 rate spring. Again, way too soft for that drop!

Basically, you need/want a spring that would take AT LEAST the same amount of force to have the front end go to full jounce (full compression). That's why the REAL ENGINEERS at FORD that have DEGREES went with ~600 rate springs and a drop of ~1/2" to ~3/4". Also, more than ~1" drop leads to many suspension geometry problems!

Yea, you "can" have a Stang that's lowered 1-1/2" and has better handling. All it means is ~$20K-$40K of suspension work. Basically, replace all of the stock suspension components with components that we designed for having the frame at that height and angle.

However, some people want a lowered look. That's FINE! That's their choice! It's only when they say that their cars with "B" and "C" springs "handle better" that they are either greatly mistaken (IMHO, most of the cases), or purposely spewing BS (like how their car with just headers now puts out over 300RWHP).

You might be able to see a part number on the springs. That may help you identify what springs they are.

Regardless, at that drop, you should have a CC plates (caster camber plates), and a bumpsteer kit. Also, FIRM struts and shocks. Stock struts and shocks are a horrible match for firmer springs.

You asked. You can take my advice (a CS/EE/ME engineer). Or, feel free to find a thread and an answer that you like better.

Good luck.

 

[83Softtop]

OK, here's the plan:

I jack up the 85 and the 83 (which I bought new and I know ain't modified in the suspension), and I compare all the suspension components to see if there is anything more than the 85's springs having been changed. If not replace the springs with new stock units, realign, test drive, measure height again, and I should be ok.

If more has been changed, I get back on the forum with specifics.

Thanks for the help, 83Softtop