If you set the governor to where the cart would run what the factory said 12-14 MPH then would it do this ?
I do understand your pain. Let us know how you come out with different engine even though i don't expect any difference.
If everything is right on these carts then you should not ever have any spit and sputter when you first take off. I own three and none do this. No MCI engines but that shouldn't matter.
One of mine did have the MCI in it but I converted it to Pre-MCI after I bought it with a large hole in block.
Like you I don't even want to see any EZGO later than 2007 in my shop. Worst mistake ever by a company but I ain't going there .
Wish someone would come up with a clone Pre-MCI . They would sell like hot cakes