i have a 91 civic that i just put a d15b8 into. its using the stock d15b2 manifold. everything bolted up fine but it is having trouble starting. it starts and runs rough for literally 2-3 seconds and dies. i triple checked the firing order and connectors and everything checks out. any ideas? im thinking because the b8 is an 8 valve motor and the b2 is a 16 valve, maybe the ecu is dumping too much fuel? help please. im stumped.

 

are you running the dx manifold or the 4 injector manifold????

 

im using the d15b2 manifold w/o injectors....basically i have a b8 block with the b2 manifolds, tranny, ecu, etc. nothing else was changed on the car from stock except for the block.

 

sounds like you answered yourown question, putting a 8 valve motor where a 16 valve motor is needed, Don't know about a 8 valve motor but seems logical, sorry not much help but throwing something out there.