Trying to figure out tdc I get there’s two different ones, my old mechanic friend used to show me that you could put your finger over spark #1 and the compression blows your finger out that’s tdc; upon reading other threads I’ve read that it’s not true tdc. My main problem is that my idle seems way too high I plan on adjust my base idle on the tbi while bypassing terminals a and b for the iac; also reading up on this topic has lead me to needing my timing set to 0 degrees before attempting. This past summer I was having timing issues and I bought a timing light my engine had no timing tab but my bigger concern was the timing mark on the HB wasn’t even showing anywhere when I was hitting it with the light so I solved the issue by plugging and unplugging the est until it felt right. I want to make my own marks on my damper along with waterpump and PS maybe. The damper is on the new end so I don’t think it spun but I don’t know if the distributor maybe off a tooth or what. Need info on find true tdc without using timing light essentially