[MissionImp]

I have some concerns with the new springs I installed in the front of my 68 Impala. I rebuilt the entire front end and when I installed the front springs I thought something was wrong when I had to compress them to get them in. The only springs I could find were for a small block and even after installing a big block with a 671 blower the front end didn't even move. Even with my brother and I standing on the front end (400lbs) it still didn't move without jumping. The upper control arm won't come off the rubber stop. Now I don't have the doors on or the glass in yet but I don't think that's going to help. I don't have the old springs to compare with. Any help would be great.
Thanks

what is the part number of the springs?


also, a big block with aluminum heads is the same as a small block with cast iron heads.

let me ask you this. how is the car sitting now with the doors off?
is the ride height where you want it? some springs are stiff and wear in over time so if it sits where you like it run em and try not to overthink it.

[MissionImp]

Sorry for the delay, out of town and I had to find my receipts. The part number on the springs (MOO 6084). I have cast heads on my big block. I'm about 2-3" above the ride height right now. The upper control arm is out of down travel. If I set the car on the ground there is absolutely no compression or travel in the front suspension.

[RWENUTS]

Do you have the springs in correctly?
The bottom coil end sits in the pocket that has the drain hole in it.

[MissionImp]

Yep, I had so much trouble getting them in I thought the same thing that they weren't seating. Everything looked correct to fit, the ID and OD. What worried me was the length and the wire size. It was a major job just to compress them enough to get them in. I've changed springs in several late 60's and 70's Chevy's and I don't remember ever using a spring compressor. Maybe I'm just getting old.

[RWENUTS]

Maybe you're a victim of the parts store swap.
Wrong parts in the right part number box.
I've seen that before.

[MissionImp]

You may be right. Ive found two springs for a 68 Impala, the one I have with a rate of 377 and another with a smaller wire and a rate of 300. I would like to find original dimensions; ID, Wire, and Length.

[66GMC]

Originally Posted by MissionImp

You may be right. Ive found two springs for a 68 Impala, the one I have with a rate of 377 and another with a smaller wire and a rate of 300. I would like to find original dimensions; ID, Wire, and Length.

Moog #6084 crosses to NAPA Chassis #277-1828.
By vehicle application, there are 5 different coil spring choices for a 1968 Impala.
Here are the specs on the 277-1828:

Attributes
# Coil Spring Coils : 9.98
Coil Spring Free Height : 16.79"
Coil Spring I.D. : 3.82"
Coil Spring Load Height : 12"
Coil Spring Type : Two Tangential Ends
Design Load : 1805
Spring Rate : 377
Wire Diameter : .672"

The part # for the springs with a spring rate of 300 is 277-3220.

# Coil Spring Coils : 9.95
Coil Spring Free Height : 17.53"
Coil Spring I.D. : 3.812"
Coil Spring Load Height : 11.75"
Coil Spring Type : Two Tangential Ends
Design Load : 1717
Spring Rate : 300
Wire Diameter : .64"

As you can see ... not a lot of differences in load (ride) heights, and weaker springs typically have LONGER free heights as they compress more to arrive at the similar "Load Height"

I can get you the specs on the other 3 as well if you like.

Edit:
PS.
I remember helping change front springs in a 1966 Canadian Pontiac (similar car). We popped the lower ball joint out and lowered the lower control arm to the floor to relax the spring and remove it. We had a 5/16" chain wrapped and bolted to contain it if it happened to get loose on us.

To install was just the opposite. We stuck the spring in, and then jacked the lower arm up until we could thread the nut back onto the ball joint. It wasn't easy, and it seemed like the entire weight of the car was on that one spring. Yes, using a spring compressor would have made the job a whole lot easier! (But we were 16 or 17 ... ALWAYS did things the hard way! )

[MissionImp]

I understand the hard way, at that age we knew everything and was 10' tall and bullet proof . Let me ask this, where should my suspension travel be? I'm sure the upper control arm is to be smashing down on the rubber stop. If the control arm was 2" off the stop I would be close to my ride height. 66GMC I'd like to see those other spring numbers if it's not to much trouble. I do know this, I'm not a victim of the wrong part in the correct box. They are Moog #6084. All dimensions match your descriptions.

[66GMC]

No sweat ... here are the remaing 3 possibilites.
As I'm sure that you already realize, the factors that influence the catalog choices are:

Engine size
Body type
With or without AC

(But IMO the "design load" is the best indicator.)
I know that you mentioned that you and your brother were 400 lbs, but I'm sure that passenger loading is approximated and included in the "design load".
Also .. don't be too quick to dismiss the weight of doors, seats, carpets, glass, etc ... just try picking them all up at once!

277-1170
Attributes
# Coil Spring Coils : 9.97
Coil Spring Free Height : 16.89"
Coil Spring I.D. : 3.81"
Coil Spring Load Height : 11.81"
Coil Spring Type : Two Tangential Ends
Design Load : 2052
Spring Rate : 404
Wire Diameter : .69"

277-3221
Attributes
# Coil Spring Coils : 9.95
Coil Spring Free Height : 16.56"
Coil Spring I.D. : 3.82"
Coil Spring Load Height : 11.75"
Coil Spring Type : Two Tangential Ends
Design Load : 1724
Spring Rate : 359
Wire Diameter : .672"

277-1929
Attributes
# Coil Spring Coils : 9.88
Coil Spring Free Height : 17.59"
Coil Spring I.D. : 3.85"
Coil Spring Load Height : 10.25"
Coil Spring Type : Two Tangential Ends
Design Load : 2209
Spring Rate : 337
Wire Diameter : .656"

[jfmmck]

For what it's worth, I put a mustang 11 after marker set up under my 50 Chevy truck with a 3.8 L V6/auto/ac so I ordered some mid rate springs. Same as you, they were hard to put in and the front end sat way up, so I cut a bout 1/2 a coil off and reinstalled, still high, but better. A few months later, I finised the truck and was able to drive it. After a very few miles the springs settled and the front end was too low, so I wound up getting new heavier rate springs and did not cut them (very hard to put in), after a few miles everything works and looks pretty good. Maybe you just need to take it for a spin to seat the springs. And it's free as long as you don't cut the springs off like I did, most place will exchange for a different rate if you don't like the ones you got.

[MissionImp]

OK this is how I'll handle it. I'm going to get her fully dressed and put some miles on her and see if she comes down like both BigChevyFTW and jfmmck suggested and if not I will use 66GMC's data to choose which spring to use next pending how far she drops. To tell the truth I really don't want to change them . Thanks to all.

[66GMC]

Personally, I think I would go with heaviest available ones. A BBC with cast heads and a blower ... you don't want that 8-qt oil pan dragging on the pavement.

[MissionImp]

Very true, but she's sitting like an old school straight axle. If I could change the subject for minute would you know why I can't see my journal photos?