auto. engine swap into manual car.

[xX-ProudDSM-Xx]

Ok so on my 95 eclipse gst I did a swap because I had a rod knock. My car is a 5-speed stick shift. I swapped in a automatic engine. The manual engine didn't have a balance shaft but the automatic engine does. What I do anything to the car? Cus my car won't go higher than 2500rpms it just backfires if I try to go faster so I thought it was the timing so I got that done and still the same thing. Main question of the post is what would be the difference now that it has a balance shaft? I'm looking for cons:

 

[krh195]

I think the only cons are that they add weight to your rotating assembly and if the Balance shaft belt breaks it often takes the timing belt out with it. It might just be a really big boost leak that is keeping your car from going over 2500rpm.

 

[ed1380]

It has nothing to do with balance shafts. They're just so that granny's don't complain about vibration.
What exactly did you swap? The 95-96 had a different cam sensor

 

[xX-ProudDSM-Xx]

I swapped in a 96 GST automatic engine.

 

[ed1380]

I don't know what you did during the install but check for boost leaks. Unplugged sensors. Check timing. And that spark plugs are connected correctly. Driver side coil does 2+3. Other coil does 1+4

 

[cola]

It sounds like you didnt correctly do the timing job, and it may be to late for your engine, If it is actually backfiring. Or you described whats happening wrong...as ed1380 said boost leaks..sensors...check and check again.

 

[caseyrock]

Your ECU could be in safe mode like on a Honda. It just runs super rich, retards timing, and engauges a really low rev limit. That only happens when something is seriously wrong. It is probably from messing up the electrical, whether it be not plugging in some sensors or having the wrong ones.