I'm trying to get a 300/360 Crate motor to pass emissions. I put to dist. back to vacuum advance. What should the timing be set at w/Vacuum advance disconnected at idle?

thx matt

Maybe TDC. You want it pretty retarded which is what Ma did back in the 70's in some cases to pass emissions. Keeps the nitrogen (nitrides?) of oxides (NOX) to an acceptable level. Not sure if subbing in a tamer cam would be something you'd want to do to get it to pass or if that would even be needed but you gotta do what you gotta do. At TDC it may need a milder cam to even run somewhat. Keep searching & here's a BTT for ya

If that is a magnum 300hp/360 crate, I think if I remeber right that is a bone stock magnum 360 long block with a carb intake on it. So not much really tamer could you get on the cam.

As said, retard timing to 0 TDC as Ma Mopar did, and lean the crap out of it. It will run absolutly terrible, but if it gets you by, then down the road after inspection you can break out the tools and fix it for the ride home.

Changing the oil can also gives you a tiny boost to the emissions. Dirty oil WILL impact the test results.

Find out the maximum allowable idle speed. That will usually help if you set it up there along with the crappy real close to TDC initial timing setting

I found removing the air filter actually lowers emissions on a carb engine hence pass