Ok, this is my last exhaust post I swear. It just that all you are so helpful..
Anyways, I installed my borla cat-back and after 2 days of driving, there is still a kind of gargling sound when I rev the engine and the rpms start to come down, I also notice that after reving engine, water comes out the tailpipe, more water than I would expect. And when I look into tailpipe after turning off car, I can see smoke, from obviously the water evaporating.
Is this normal, I wouldn't think so and what can I do to help/fix situation? Thanks.
Where are you at? It's common for condensation to occur in the exhaust system, which is why they tend to rust from the inside out. The noise you describe I'm unsure about. Your description didn't seem like it should of concern.
When you rev the engine and hold it at the red line how does it sound? When it makes the noise you describe, do the RPMs drop off despite you trying to hold them at the same level? I've heard many performance exhaust systems on cars that tend to "bark" when brought down quickly from high RPMs. Could be the design of the exhaust system.
Well, #1 I am in San Diego, California and I guess, now that I think of it, there have been some dewy mornings recently. Also, for the other question, the RPMS drop only when I let off the gas and only when the RPMS are coming down do I hear the noise.(Maybe that's because engine is too loud to hear or it just doesn't happen.) But if it is no big problem, I won't worry. I'm just new to modifying my car and did not know what to expect right away. Thanks for your help.
The free-er flowing exhaust is just letting more noise come out. Subarus do it all the time - put a free flowing exhaust on and you can then hear a lot more of the backfiring when you lift off the throttle.
I have a Gibson cat back and I get the same sound sometimes when I let off the gas, especially after going up a long hill at 55mph. I think that Horatio is right that it is just a more free flowing exhaust so you hear more off the backfire sound. Can't help you with the water though.
Bryan, the noise that you are hearing is the exhaust backpressure. Although that is not a good sound, as long as you don't have too much of it it's OK. However too much could screw your engine. I know of someone who had an open catelytic convertor but it was junk and wasn't working. However he didn't know this. There was nothing to stop his backpressure and it blew his head gasket. With the more freely flowing exaust like you have it will allow some backpressure. As I said though as long a it's not too much you should be OK. Hope that helps.
Yes, thank you very much. I have also noticed a very small amount of air coming out between the cat and muffler, where the two pipes go into eachother. I think this is because the cat pipe was cut a little short while taking off the old muffler. I know there is air coming out because i put a piece of paper around there and I can see and feel air hitting it. Shuold I just buy a new cat or is this ok?