What's up with my engine rebuild?

Waternut

Customizing addict
Location
Macon, GA
I can't figure out what's going on. My crank let go a couple weeks ago and since then I've gotten another crank, new pistons/rings, and gave the cylinder a new hone. Installed everything, torqued it all down, leak checked it, and hooked it all up. Well, it runs like sh*t!! Even the idle isn't consistent.

There are three changes I made and I'm struggling to see how any would make it run any different at idle and cause it to not rev properly. First, the final backfire that eventually ended my engine blew a hole in the exhaust hose which I repaired by adding a 2" PVC elbow in place. Second, I realized the timing I was running all summer was backwards and instead of running 30° static timing on my total loss, I was running about 15° static timing. I've since changed it so that my static timing is around 25° as that is the max I can get out of the stator plate. The last change was adding a little extra oil (about 32:1) to the gas for engine break-in.

The most possible in my mind is the timing but if the flywheel is supposed to spin clockwise when looking at it as I've confirmed in so many ways, I don't see how running 25° static timing is really an issue or would cause the engine vary the idle speed. The only other things I can think of are the fuel tank managed to get water in it, the oil ratio is worse than I thought, or the ignition coil just randomly went out with everything else.
 
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Matt_E

steals hub caps from cars
Site Supporter
Location
at peace
my static timing is around 25° as that is the max I can get out of the stator plate

Assuming that you have MSD TL, you should be able to get a lot more than 25 degrees static out of that plate.
Something isn't right with that.
 

Kennay

Squarenose for the _____
Location
Myrtle Beach, SC
Not true on the plate.... I was only able to get about 20 degrees if I remember correctly. I had to take a dremel and make the slots a little longer. Charles can back me up on this because I was in his shop when I set it up the second time when I got the BB motor.

I think it has to do with the vintage of the pick up plate.
 

Waternut

Customizing addict
Location
Macon, GA
I dread the thought of having to pull the flywheel but if I flipped the stator plate around, would it produce different results? I assumed flipping it wouldn't do anything. I have a different plate laying around that I can try if everything else fails though.
 

Waternut

Customizing addict
Location
Macon, GA
Well it seemed to run better today but I didn't tighten the exhaust hose on the waterbox enough and it came off before I could take it out. I ran it briefly with the hood off while on the trailer and exhaust was pouring out of the engine bay. I should know for sure tomorrow if everything is ok or not.

Out of curiosity though... What can a backfire do to a carb? I didn't think to look until I just read something about JSS fixing carbs with backfire damage. If it blew the diaphram or something, that could exlain a lot.
 
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