Post suspension replacement questions

[suki243]

Hey all, a while back I had my suspension replaced; the whole 9 yards, leafs, shackles, saddle perches, springs, shocks, ...everything. I had a professional shop do it; He took care of the setup and everything.

It's a bit stiff for my liking, 620s, and 5 leafs, with new gas kyb shocks all around. I think i may have to stay with this setup for a while though; because the place i bought my rims off of giving me the wrong backspacing and cause i didn't check them + the fact that for some reason the tire wrapped around it is extremely tall; (i forgot the exact measurement) Is it true that this stiffness will keep tire rubbing to a minimum? Right now the tire doesn't rub against the top of the fender, but rather on the front of the fender, but only when i go really hard into a bump or unexpectedly.
I enjoyed the stock ride feeling; what spring rating were those?

But, the problem i'm having is that after i go over a bump the springs in the front moan... and its pretty loud and embarrassing. Why is that?

The second issue is that everything is rattling now! soo many more rattles! My window regulator just failed on my passenger side, my passenger side rod that connects the outside handle to the striker keeps popping out (its worn out)
Is this normal? what can i do to reduce this? its getting really annoying.

 

[2+2GT]

The moan in front is probably the upper control arm pivots. Get the special zerk fittings and grease them. The harshness is due to the over-stiff springs. Assuming the fronts match the 5-leaf rears, you have massive overkill. Even the Cobra Jet and BOSS only had 4 leaves.

I don't suppose your specialist used urethane suspension bushings? They contribute to ride harshness and can be a safety hazard:

View attachment 254589

 

[rbohm]

what tire size and backspacing were you given? as for the springs the stock springs were 380lb/in rated in front and about 120lb/in rated in the rear. you can change out the springs fairly easily, and i am sure that there are a number of guys here, or on other mustang forums, who will buy your curent springs. i recommend the stock gt spring in front which is rated at 480lb/in, or step up to the 540lb/in spring like i am going to use on my mustang. in the rear use a 4 leaf spring rated at around 140-160lb/in.

 

[suki243]

I don't suppose your specialist used urethane suspension bushings? They contribute to ride harshness and can be a safety hazard:

Yah he did; Got a sway bar put in as well

what tire size and backspacing were you given? as for the springs the stock springs were 380lb/in rated in front and about 120lb/in rated in the rear. you can change out the springs fairly easily, and i am sure that there are a number of guys here, or on other mustang forums, who will buy your curent springs. i recommend the stock gt spring in front which is rated at 480lb/in, or step up to the 540lb/in spring like i am going to use on my mustang. in the rear use a 4 leaf spring rated at around 140-160lb/in.

Foose Legends 17x8 w/ 215/50R17 tires The back spacing is 1/4 inch too far out; I'll have to pull the rim and redo the measurement cause i forgot. The height of the tire is massive though; when i get back home i'll get a measurement. I compared it to a 18" 245 tire and mine was still taller.

GAH! thats a huge step up no wonder its so damn stiff. The rear is like a rock... go over a speed bump and the rear is stiff like no other, but the tires don't rub anymore; the rear tires were getting cut up pretty badly. And the Previous springs had taken quite a beating the car wasn't level at all.
The guy who installed it took a pretty penny He's been in Mustangs Monthly and was recommended by quite a few folk.

I suspected the UCA to be the culprit, the ones he replaced have a swiveling zerk so it shouldn't be too bad to grease, its been about 500 miles since I had them installed. He said to come back sometime so he can check on everything and make sure everything is in order.

How about hte KYB gas shocks? are those good? The reason why i even trusted this guy in the first place was cause when i was researching setups everyone had such a vast opinion. I think I'm just going to order grab a track's replacement gt kit and my buddy and i will just replace the coils and springs.

 

[rbohm]

a 215/50-17 tire is 25.5" tall so it isnt out of line as the stock tire on a mustang was 25.6". as for the KYB shocks, i like them, but they are fairly stiff shocks. you can change them out to the KYB gr2 shocks for a better ride instead of the springs if you like. the change wont be huge, but it might be enough to make the ride more to your liking.

 

[Rusty67]

The rattle is of course because everything is now so stiff that the rest of the car has to absorb the rest of the shock that the suspension is no longer dissapating.

 

[zookeeper]

Your springs are NOT overly stiff, it's the shocks. I have 5 leafs and GR-2 shocks and my car is fairly soft, in fact much softer than my '88 GT (stock) and my wife's '69 Corvette (also stock, and both of those cars are liveable.

 

[chris66dad]

I have 620 and 4 1/2 leaves in back and it is firm but not jolting stiff. I have gas shocks by a different manufacture. I am running 16x8 torque thrust II (4.5 bs) and 225 50vr tires with no rubbing.

You really need to fix the tire rub. I could cause the tire to fail if you really slam it hard on a compression.
I would look into rolling the fender lips to eliminate the rub problem

 

[suki243]

a 215/50-17 tire is 25.5" tall so it isnt out of line as the stock tire on a mustang was 25.6". as for the KYB shocks, i like them, but they are fairly stiff shocks. you can change them out to the KYB gr2 shocks for a better ride instead of the springs if you like. the change wont be huge, but it might be enough to make the ride more to your liking.

Yup its 25.5" The guy at the shop said thats huge then showed me his car with a bigger size tire and rim and his tire was about 2 inches smaller.

I have 620 and 4 1/2 leaves in back and it is firm but not jolting stiff. I have gas shocks by a different manufacture. I am running 16x8 torque thrust II (4.5 bs) and 225 50vr tires with no rubbing.

You really need to fix the tire rub. I could cause the tire to fail if you really slam it hard on a compression.
I would look into rolling the fender lips to eliminate the rub problem

As of right now I don't have rubbing unless I'm really going fast and its a serious dip, even then its not at the top its on the front of the fender; I did have the fender lips rolled already, but to fix the front part, I have to get them cut re-rolled and repainted.

I'm pretty sure the gas shocks contribute to it; I just don't want that if i change something out that the tires start rubbing again. Right after i got the rims put on all 4 were rubbing; then i took it back to the dude who put em on and i told him i was unhappy he then decided to put in those damn twistie spring spacers in the front, but that made the front higher than the back; and instead of the fronts rubbing it was the back.

 

[Rusty67]

Unless they were custom orderded, I would take them back where you got them and get yourself the proper rims.