Noticeable and quantifiable are extremely different. You can notice something that isn't truly there. Maybe my butt dyno just isn't as finely tuned as others.

Again, the only real data I've seen in this thread shows that the gutted cat produces less power. I'm not sure how people can still argue this fact without bringing real data to the table.

And Bose, very interesting test with the filters as well. I agree that there's no way in heaven I'd remove the filter from my car!

 

Id imagine it really depends on the shape & size of the cat, but without that media in the cat, you lose all the spaces/honeycomb that would straighten out the airflow, so you should get some more turbulent flow with the cat gutted. This may cancel out any gain from opening up the space in the cat

Ether way, id like to see proof of loss or gain, especially with the gains you claim on the gutted cat... I doubt itd be much if any

 

Relax and take your meds. Just an example of restriction.

 

If you read the article it says it's not a restriction, a proper filter will suck in more air than an open air box.

 

Fluid dynamics? Whats that?

 

I did this at the track last weekend and lost 3mph which is a good amount of loss hp. I did atleast 5-8 runs with it out. Also did another 3-5 runs with the airbox propped open. You have to try stuff to seee if you can gain a extra MPH or .1 E/T.

 

OK sooo I guess I'm just going to have to try one for myself. Why does everyone seem to hate the OBX midpipe? I dont want to search. Anyone have one?

 

Fluid dynamics and vibrations/resonance.

 

Agreed, You have to try stuff to see if it works. My drag bike works better without a airfilter but It also has a pretty big stack on it.

 

Well, Just ordered a mid pipe. I'll get back in a few weeks...

 

I guess my point of view is if you have the cash to go turbo you have the cash to at least get an rb pipe.. having a mid pipe is just as useful as a BOV IMO.

Maybe I'm off but I would much rather sell my stock cat for $200 and buy a $125 mid pipe.

 

Midpipe numbers are all well and good, but that won't settle the gutted vs. non-gutted CAT debate.

 

I did not gut my cat because I could not afford a midpipe.

The reason was because I need to keep my car as quiet as possible (cops in my area are bad) and the only way to accomplish that was to gut the OEM midpipe.

I could have gone with a Mazsport midpipe but I did not like that you need spacers for the cross members.

 

But it will settle the gutted cat vs. midpipe issue.

 

hmmm well to each their own I suppose.

 

OK, its been awhile now since I installed a catless midpipe. I gotta admit theres more top end power. To the point where the vehicle revs past the redline(Easy) and sometimes kicks on the fuel shut off on late. The only minus was there was a rasp sound at around 2000 rpm. Belive it or not I got 90% of the rasp out by wraping the pipe with header heat wrap tape.

 

i think that happens because the wrap is muffling a bit, where as the stock pipe is thicker, but i am just talking out my ***