Springs.....................

[NavyCPO]

When I look at my car, it looks to me like the front end sits pretty low and pretty low over the tires like the springs are seriously worn.  Today I noticed that it looks like the passenger front is a bit lower than the drivers side and the back seems like the drivers side is a little lower than the passenger side.  I put new airi shocks on the back and they raised up the rear a bit and I haven't checked to see if it helped level the back up yet, I think it did some.  But being a SBC Car is it common for these cars to sit so low in the front end?  And is it common to have to replace the springs on these old girls?  Mine is a 70 so she's 53 years old now.  Or could it just be me?  Also if I take measurements and she is sitting lower on the passenger side, what are ya'll's (that's a southern word) thoughts on using some of those spring spacers to level her up/give her some support until I could get some new replacement springs?  Should I order BBC springs or stick with the SBC springs and just freshen them up.  GO!!!

[420ponies]

As for the front springs, I had bought these through Lutty's. Just look for your fit ,A/C or non ,SBC or BBC. As for the rear I use the Moog Vari - Rate just because you can load the trunk and no sag. Also, I have Air shocks and run 25 psi just so they work running down the road.

[MC1of80]

The pic you have shows your car sitting just fine. Although it is not uncommon to have a weak spring. I would first look at the shocks and if questionable, replace with a gas type shock of your choice and then measure the ride height. 

[Dtret]

As said above correct spring for the application. You probably don’t want big block springs, may sit to high for your liking. Yes check shocks as said. You can get by with spring spreaders for a little while. The twist in ones can pop out on big bumps and the bolt on are a pita. 

[cny first gen 71]

It doesn't look like it's sitting to bad. Take some measurements to know  for sure. On mine the front springs have been changed at some point before I bought the car. I changed the rear with cargo coils and added spacers to the bottom to get the stance I wanted. At different angles it will look different. Put it on a level surface and measure all 4 points and see. As far as the front spacers I've personally never liked them.

[MCfan]

Dale, do you have a Build Sheet for your '70?  If so, check box 13 for the 2-letter code identifying the spring that GM selected from 10 possible front coils when your Monte was assembled.  Even if your front coils have been replaced or sagged over the years, the specs for the spring used in assembly (see spring table below) should get you back to "stock" front end height for the options originally built with your car.  You are not going to find the original part numbers for replacement springs so you have to compare the original specs with specs of available replacement springs.

As you look down the table of 10 possible springs below, you will see that the springs increase in preload force (pounds at working height of 11.7" in the far right column) from 1360 lbs for the "lightest" AF spring to 1760 lbs for the "heaviest" GQ spring.  Your car was built with the spring that had the best preload for its total weight, including options. While small blocks obviously weigh less than the big blocks, engine choice was not the criteria for factory spring selection which was based on total weight including all options. For example, my low-optioned 402 4-speed '70 was built with the AO spring while a heavily optioned small block automatic car may have been built with a heavier spring.

Because I added AC, power steering and larger front tires, I chose to install 1" spring spacers in my original AO front coils to avoid tire rubbing on tight turns.  I used the split-circle 1" rubber spacers near the bottom of the coil (see photo below) to get some minor lift without stressing the spring.  I would personally never use those metal plugs that twist-in between the coils because they create stress points during operation.  As you may know, spacers effectively reduce the working height of a coil spring and thereby increase its preload so use them in moderation.

Coil springs can take a "set" and/or weaken over the years, so if you decide to replace them (instead of using spacers) you will need to calculate the preload of the spring you select to either match or slightly exceed the preload of the original factory spring.  The calculation is easy once you have the following spring specs: free height (in inches) and deflection rate (lbs/inch of compression).  Simply subtract 11.7" (working height) from the spring's free height and multiple that difference by the deflection rate. For example: using the popular replacement Moog 6330 specs: (17.5" - 11.7") x 293 lbs/in = 1700 lbs of preload. Now compare that to the preloads shown in the right hand column of the table below and see where it stacks up (almost the same as the AQ spring in this example).  I agree with others that you probably shouldn't select a spring with the heaviest preload unless you want the front end to sit pretty high.  Preload is definitely the most critical factor in determining the static height of your Monte's front end. Good luck.