I am in the middle of breaking in the cam and the idle was high (after it's on for a very short amount of time it revs to beyond 3k - then I shut it off).

WHen I turn it on I touch the pedal to bring it up to 2k (it cranks up and hangs around a low idle and feels a tad shaky before I bring it up to speed; as it works up to 2k it's even and sounds smooth). Sometimes it goes to 2k for a few seconds then does the high rev, other times it acts normal and I have to keep blipping the throttle to keep it around 2k. I can't seem to just simply hold the pedal slightly open and it stay at 2k like I have done before.

I figured maybe it was a vacuum leak at some of the ports as I tightened them up before putting on the TB because the fittings moved a bit when I put the hoses on. I was able to tighten them all a bit, and it seems to hover around a more stable lower idle when turned on, but it will still jump rev up to beyond 3k RPMs after being on for a very short amount of time (20 seconds roughly).

My manifold bolts are tight, although I am re-using a metal Omix-Ada gasket. If there is an exhaust leak I wouldn't know since I have the exhaust disconnected and it has to be that way until I can get it to an exhaust shop. Cats were plugged from an event the year prior. This is a rebuilt engine with a new cam.

I don't want to keep turning this thing off and on during cam break in so I'm going to let it sit until I can come up with an idea what it is. It didn't take long for it to reach full operating temperature after I got it running.

 

I found it. I noviced the manifold installation like never before. I didn't know this was even possible. My manifold has the stud holes on the bottom and I am guessing the right side is sitting on top of it. I was wondering why it kept shooting flames into the sky like a 12,000 HP dragster.

 

Yep, that will do it every time!

 

It ran flawless after that was corrected. I wasn't paying attention to the time and was breaking it in loud and proud after dark. I wonder how much of the neighborhood heard me. After it was done it came down to a nice smooth even idle. I haven't felt so excited about a smooth idle in years.

It feels like such a waste of oil and a filter.