Hey everyone, long time lurker, finally joined today with a question.
I installed a new exhaust on my 92 civic with a d15b7 motor.
The exhaust is full 2.5", came with straight headers no cats.
It seems the car has quite a vibration and runs a little rough now that the exhaust is on.
Is this something I should get a tune for or will this possibly go away with some driving?

 

That is really too big for a stock D15B7 engine... it likely will not cause any peak power loss but it will lose midrange performance. I can't tell you what the vibration is... it may just be exhaust harmonics. Tuning is always best for maximum performance from a modified Honda/Acura.

 

Since your car is OBD1 I assume that you do not have a check engine light. The exhaust diameter is pretty large but it wouldn't make that big of an impact on the drivability of the car. You should confirm that the new exhaust isn't hitting anything which is causing the vibration (oil pan, rear LCA, the body itself, shift linkage, etc.). What does a little rough mean? Not smooth idle? Powerband feels sluggish? That "not smooth" feeling might just be influenced by the new sound the car is making.

BTW: Where in Boston are you from? I live nearby.

 

No check engine light, Ill double check that its not hitting anything. It drives okay but at idle it seems the whole car has a pretty noticeable vibration.

I live in Braintree, originally from Dorchester. We have meets near the Braintree mall every week if you ever want to come check one out.

 

huh???

 

Odd. I wonder if there was a coincidence with say a broken motor mount or something.

Shooting you a PM.

1992 Civic = OBD1... as in there's only one oxygen sensor - that is before the catalytic converter - so with a test pipe there is no check engine light.

 

Oh you were asking if there was a CEL code, not a CEL light.