You just buy two boxes of 12.......
The 975 spring is the "Inner" spring on a Big Block Chevy setup.
They have seat and open pressure close to the spring rates of the 2JZ stock springs. (So slightly higher than the 7M springs.)
They are a tight fit into the head, but work with all the stock retainers/lifters etc. When you set them side by side, they are taller before they are installed. But they can be compressed more before they coil bind. (So you could run a higher lift cam, and not have any problems on these springs.)
The metal is the latest stuff, and Comp claims it's cleaner than ever, and thus has fewer failures. (Cracked springs.)
I use them, and have had no problems, with a few over-rev moments putting my engine up to 7150rpm at one missed shift. (As reccord by the Eman.)
Based on what most of us have, old 100+ thousand mile springs, or the cost of the new OEM springs being outragous, these for less than 70.00 total are THE BEST DEAL FOR SPRINGS FOR THE 7M. Hands down.
Sure you can spend more with "F-co" springs, locks and other stuff, but if your running the stock ECU/TCCS, why spend that money where it's not ever going to be needed? (If you plan on running your 7M to 7500 or 8000rpm for extended time, then you can spend the extra money, but at less than 7k rpm, these from Comp Cams are excellent upgrades from stock.)
Why do you think Comp sells the 975 in boxes of 12? LOL It's not for any Chevy aplication... They should just market them in boxes of 24... but selling them in boxes of 12 keeps it easy. (They come in a box made for batches of 16 springs, and that can be used on V8 two valve engines...)
