Yes absolutely! I just did it on my 86.5 D21. The gains were incredible and cleaned up the idle. Follow each and every main vacuum line and cap them as shown earlier In the post. I removed every single vacuum line besides brake booster. My emissions junk ended up being full of water which was really odd to me! But my head just ended up being cracked a couple months ago and I rebuilt the engine, and I didn’t do all of the emission deletes/ cat removal til after the fact. Really surprises me how much better this z24i runs without the extra emissions junk.