is running a flex pipe really nessacery?

 

No, but it will help with the movement of the downpipe and exhaust if it hits something and help against cracks in the exhaust. I use one for some give in my exhaust.

 

how much HP difference is seen between a 2.5" and a 3" down pipe on a regular t3t4 setup?

 

Depends on how much boost you are going to run and what kind of turbo you have. I would just go ahead and get a 3" exhaust and downpipe to be safe because you don't want to have a restriction of your exhaust if you want to go bigger down the road.

 

For a turbo setup,the bigger the exhaust the better (depending on your power goals). As for a flex pipe, they make your exhaust rattle less and help with vibrations. I ended up getting a downpipe off of ebay and used it just for the flex pipe because it was so cheap...

 

I have a ebay downpipe and the metals so thin it was disinegrading (cell phones font have spe?l check) during welding and the braids in the flex pipe ripped open. Complete fail

 

2.0 sleeved lsvtec/ garrett t3 57 trim .48ar ex, looking to make 300+ maybe 15psi??
thing is that my piping is only 2.25" and it still has a stock civic muffler, i dont want it to be loud so im keeping the stock muffler. how bad will it b if i tune on open downpipe and run it with the muffler on daily? will there be lots of detnation occuring because of air restricting and maybe different a/f ratios with the stock muffler?

 

wheres a good place to order quality flexpipes?

 

oh and which one are u guys running for flex pipe? the interlock liner or the braided liner design that is inside the flex pipe?

 

Tune on open downpipe with stock muffler? So you will have a downpipe, huge gap where exhaust piping should go then a muffler hooked up to nothing? That makes no sense. If you don't want it to be loud buy a apexi worldsport not a fartcan. If you want 300+ you'll need 3 inch all the way back from downpipe. If your car is turbo and doesn't have a fart can you'll be fine

 

not sure if i made myself clear, but what i was saying is the down pipe will be connected to a 3" to 2.25" test pipe that connects to my 2.25" piping that goes all the way back and connects to a stock muffler, i will tune it without the test pipe so the down pipe will be open, once its tuned i will bolt the test pipe back up, and daily drive it, that way it wont be loud, will that mess the tune up enough to detnate the enigne?

 

It will throw off the A/F ratio because it won't be getting out the same about of exhaust as before. You're going to want a 3" exhaust from the turbo back. Get an 80mm Apexi WS2 catback with a resonator and it'll be really quiet.

 

I highly suggest running a flex pipe unless you enjoy broken studs and manifolds.

 

that exhaust looks nice but here, i'll b too paranoid to be driving with a modify muffler, these popo will pop ur hood if they see any bling bling under your bumper. thats why im left to a stock muffler.

 

Then just cut off the tip that comes with the Apexi system and paint it flat black and it looks stock. My Apexi is dirty as all hell and it looks like a stock muffler with a tip lol.