help, hard to start and backfires
 

just italled new water o-rings and cleaned all the interals...car cranks but sounds like very rich and hard to get it to fire... it fires after 1 min on cranking, wont idle, makes poping noises, backfires at low rpm..

mechanic set the timing, and said it something else.. im thinking it could be 1 of the lower injector stuck open.. i want to try to swap upper inj for lower inj, but dont know if they r same ressistence...

i will take any sujjections.. thanx

you should be able to swap them.
so you pulled out the engine and rebuilt it? make sure it's not something simple, like a disconnected ground wire on the block, ect.

mech set timing?
 

has this guy set timing on a rx7 before?could have the timing marks on the CAS mixed up..just got my 7 and i'm not lettin anyone touch the electricals ..if you can check the timing yourself grab the timing light and check his work..worth a shot.....( sounds like it is out of whack)..p.s.hope i'm not insulting anyone with this suggestion..

Have you checked for vacuum leaks?

I second that. Check for vacuum leaks.

i did check for vac leaks, mechanik does 90% rotaries, gounds are ok, mecanik said that when i install the front pulley i have to look for e shaft lock key( 9 O'clock
and pulley timing marks would be 12 O'clock), just want to make sure thats way to do it..

also r the secondaries and primary injectors same imp?