I can’t drive 55

[N PRGRES]

Had the girl out for a decent highway run this weekend. With the 3.08 rears and 27” tires she was turning about 3000 rpm at 65-70 mph.  She ran like a dream even if it was a tad unnerving keeping the thirty 400 at that high of an rpm.

I did realize that I might be a tad too low as I seem to scrape the mufflers quite a bit. 🤷🏻‍♂️

[gm muscle]

Before I replaced the leaf springs, I had the same problem. These cars do tend to sit a bit low in the rear. For about 20 years or so, I had air-adjustable shock absorbers in the rear to level the rear end height...didn't care too much for the ride quality but the car looked good. Interesting...I have 3.23 gears out back, with a 26.6 in tall tires and with the trans in 3rd gear (1:1 I believe) I get around 3K rpm. Maybe slightly less.

[N PRGRES]

Before I replaced the leaf springs, I had the same problem. These cars do tend to sit a bit low in the rear. For about 20 years or so, I had air-adjustable shock absorbers in the rear to level the rear end height...didn't care too much for the ride quality but the car looked good. Interesting...I have 3.23 gears out back, with a 26.6 in tall tires and with the trans in 3rd gear (1:1 I believe) I get around 3K rpm. Maybe slightly less.

Springs were replaced a few years back with pro touring F body rear springs. It has the adjustable shackle so I might need to take it up some.

[FormTA]

I have the same rear spring set up. I moved mine to the lowest setting and it was still to low so I made another set of rear shackles with the hole spacing 1/2" farther apart (which only gives a 1/4" or less lift). So far that has been ok s far as dragging the bottom of my car on things. Other than speed bumps, it clears most things like driveways and such.  I bought air shocks to help me even more but haven't installed them yet. The rear of my car is still lower than the front even with 2" drop Hotkis coils up front. BTW my car runs around 1500 -1700 at 55/60... I have 3.73 and a 4L60E, I usually keep it in third because in overdrive, it is barely running 

[N PRGRES]

I have the same rear spring set up. I moved mine to the lowest setting and it was still to low so I made another set of rear shackles with the hole spacing 1/2" farther apart (which only gives a 1/4" or less lift). So far that has been ok s far as dragging the bottom of my car on things. Other than speed bumps, it clears most things like driveways and such.  I bought air shocks to help me even more but haven't installed them yet. The rear of my car is still lower than the front even with 2" drop Hotkis coils up front. BTW my car runs around 1500 -1700 at 55/60... I have 3.73 and a 4L60E, I usually keep it in third because in overdrive, it is barely running 

Thanks for the info, do you by chance have a side photo of the car that shows the stance?

[roadking77]

Sounds like a fun drive. Glad you were able to get the car out for some driving. My car sits fairly low in the rear and driving solo with nothing in the trunk I usually dont have a problem. With my 2 of us and the trunk loaded with a full size spare and jack it does tend to drag the mufflers on occasion, but only if there is a big bump ahead. Not enough for me to worry about it at this point.

[FormTA]

It is interesting how much the height can change. If I have my wife and two kids in the car (14&16) she really drags and I can even feel the weight.