I was wondering would i loose power if I was to do a 2 1/4 straight pipe from my headers all the way to the back with without muffler? Or I should just do the straight pipe to my original muffler?

 

I'd put a muffler on there. A high flow cat wouldn't hurt either.

 

I might put a muffler on..depending if I loose power or not with doing straigt piping all the way with no muffler

 

your exhaust would sound like straight poo with straight pipe. put at least a resonator on or somethin. doin this is ghetto as fugg

 

Stock d15 yes you would lose power. It would be pointless unless you have a built motor flowing a lot of air in and needing to get it out.

 

It's a Ls swap Crx...I'm doing the swap this weekend and and piping after I'm done. That's why I'm asking in advance

 

either way clipsed's statement is still true.. if its a stock motor. you are going to lose power unless u are losing power already because its too restricted

 

he will need to make the pipe bigger the stock ef exhaust is too small and restrictive but your going to want to atleast have the muffler to give some back pressure

 

Yea that's also true...are their possible way I could fit a Gsr muffler on my Crx? With access to a shop n Welding machine?

 

I don't agree with that.
Maybe I'm misinformed, but as far as I know, back pressure is never good!

What you want is high gas velocity and the lowest back pressure you can get.
The mistake is that some people go with too large diameter piping, bends, length header, etc and then the velocity of the gas is diminished.
By going with a smaller diameter pipe (or whatever) happens to introduce a little back pressure, but the velocity is increased properly, then that will function way better.

 

Im going to put the basic bolts on..like headers and intake but my headers are gonna be Itr headers...would 2 1/4 piping be good enough for N/A Ls Vtec?

 

you make power through making the engine breathe more efficiently. you could straight pipe it, which would eliminate a lot of flow restriction, but it should also be matched by an intake, and possibly a header. 2.25 would be a great size. it would allow for a decent ranged power band without sacrificing too much torque. but most honda motors sound like straight *****, so i would put a muffler and resonator on there.

 

On my ls powered 4 dr I have 2.25" from the test pipe back to a little muffler. Also have skunk2 im, and a header. I will be welding in a resonator soon.

 

You are correct, back pressure is never and i mean NEVER good for anything. Even for emission control during overlap.

 

I ran 2 1/4 with only a high flow cat and a resignator for a long time on my ITR swapped hatch. I then went to a single outlet magnaflow muffler because of the noise.