420A Bolt-on TechIntake, exhaust, ignition, fuel system, cooling, etc - specific to 2G N/T DSMs. New Members must limit their 420A tech posts to this forum.
I have an Apex-i Dunk universal muffler on my car with stock piping. It sounds kind of ok but not what I expected. Anyways my car is an a/t and when it shifts from 1st to 2nd it makes this wierd a$$ noise kind of like the exhaust is inhaling air. It only does it at high rpms like above 5000 I thought it might be the converter , so I gutted it. Well its not the converter and on top of that my car lost around 15 to 20 hp because of this mod( f*ck up). Now my car still has this wierd noise when shifting gears and my car is even slower than before. If anyone has experienced this noise problem or can help me out with it please do. Your help will be greatley appreciated.
I knew gutting the cat would make me lose backpressure I really didnt know how much I would lose until I done it, but now I know. You learn from your mistakes.
are you sure that your transmission isn't slipping a bit, causing the engine to rev a bit between shifts? and i don't think you would lose 15 to 20 hp from gutting your cat...you just lost some low end torque
If I cant lose HP by gutting the cat then I guess my car is f*cked. I used my G-Tech on my car to see what it was running in the 1/8th so I could double check my vehicles data. Everything was accurate. Then I tested the HP. On the first couple runs it would turn out 98 to 100 hp. After gutting my cat I tested it again and it said I had 78 whp I thought my gutted converter made me lose power but I guess not. Thanks for the help though, I guess Ill get it checked out.
Oh yea now that I gutted the cat it sounds more ricey tha it ever has. I didnt really like the mufflers tone when I first got it either. What can I do to make it deeper and not get rid of this muffler.
i hope you had a resonator already. if u have one of those big mufflers with no resonator or silencer it is loud dont u get annoyed driving hereing the muffler whining noise all the time? and if u dont have a cat anymore ## ###### a pretty loud fella. but if u wanna get rid of the sound just go buy a new cat. get one of the "high flow" ones for like $50.00. and if u wanna get rid of some noise make sure when they welded ## muffler on they used a resonator and put ## silencer in.
Well giving it a lot of thought I think I will sell this muffler and put my stock one on for a while. When I get tired of that I will buy an Apex N1 (WITH A SILENCER) to go on there with custom 2.5 in piping, I hear those sound pretty good and a lot of people on here have them so obviously there is something good about them. But thanks for all the help, it is greatly appreciated.
