I am redoing my suspensions on my 80 Olds cutlass supreme. I am replacing the 260 with a 350 and am unsure if I need to have heavy duty springs.

I also have struck out at the local parts stores in ordering some springs, is there a place online I could get what I need?

Thanks.

 

The weight difference between the 260 and the 350 won't amount to much, although if it's an older 350, it might be slightly heavier. There are a number of springs that are available, and can be used to level it or to improve handling. If it's any help to you, my car is relatively light, with a 455, and I'm going for improved handling and stock-ish appearance. I'll be putting Moog 5660s in the front and 5409s in the back. These might be slightly lower than stock, but my stock worn springs are over 30 years old, and they're lower than stock too. I believe you can get Moog from Jegs and Summit, but some parts stores can get them too, such as O'Reilly's.

 

I doubt you'll need new springs unless yours are worn and sagging or you just want to change them for another purpose.

Here is a list of moog springs that you can cross dimensions and specs and get a part number (it can be sorted by columns):
http://www.moog-suspension-parts.com...il_springs.asp

 

Thanks yall. I'm restoring the car as it was my first car. I have the body off the frame and the frame is painted and ready for parts.

When I last drove the car 10 yrs ago the passenger side sat lower in the front. I figure I'm redoing the car so I'll go new/rebuilt with everything.

 

Some other suggestions then, in case you want to upgrade handling. You can box the rear control arms, some say just lowers, some say you can do the uppers too. I boxed my lowers and this helped. There are also heavy-duty GM bushings that will work at least in the rear to tighten it up, I believe these were F-body 1LE bushings. You can also add or upgrade sway bars, there was a factory rear sway bar if you don't have one, and there are numerous upgrade front sway bars, including I believe a 34 mm hollow and 36 mm hollow that were used on F-bodies. Finally, there's also the factory fast-ratio steering box that guys have had good experience with. There's also a ton of aftermarket stuff, I tend to stick with factory-type parts, so I don't have a lot of information on the aftermarket items.

 

I had an 80 with a 260 in it when I bought in 1990 and within 2 weeks it had a 1975 350 in there. I beat on that engine for a little over 3 years (blowing the rear end 3 times in the process ) until it was time to let that one go. I then swapped in a 455 and ran that for a month until I spun a rod bearing. It ended up with a 1970 350 in it and the 455 went where the 350 was.

I never once touched the front springs and it never gave me any inkling that they needed to be addressed.