Hello,
First forum post so I apologize if I am doing something wrong

I have an cammed LS2 swapped into an 89 BMW E30.
The motor has always popped a lot on decel and every once in awhile instead of popping it makes a Jake brake sound. I have also noticed that when it pops on decel the timing is at 8 degrees and when it Jake brakes it goes to 5 degrees. The motor also loses power but will still rev through the rpm range. Is this this something in the tune?

Also, when I pulled the car out from sitting this year it seems to fall on its face when wot. I just changed the fuel filter/regulator and the fuel looked pretty dirty. So maybe clogged injector?

Any suggestions for these issues would be helpful.