gc86

iTrader: (26)

Would this yield anything? has anyone does this before? I was thinking about it and it kind of seems iffy since the stock midpipe later turns into a single pipe than splits again at the axleback section. Any thoughts?

flowrider

iTrader: (9)

Well, I have an F, but the similarity of the two, V engines in the same chassis, that I feel I can answer this. What I did, was to eliminate the secondary cats, and substitute an X pipe as you want to do. I then continued into two glasspack resonators and on into the stock mufflers. IMHO, it sounds better, but is still quiet, and puts out more power. It cost me about $450.00 for my conversion from a from a two into one into two exhaust system to a full dual system

Lou

kjl2007

Well...my exhaust removed a pair of the Cats, but its a H pipe.

Kurtz

iTrader: (1)

Put it this way-

Axle-back systems on the IS350 gain about 7 hp.

Full, removing the 2nd cats, exhausts, add 12 hp.

Full, replacing the 2nd cats with aftermarkets, adds 10 hp.

So just removing the 2nd cats entirely makes a difference roughly somewhere between 2-4 horsepower.

Less, I imagine, on a 250.

Modern cats are pretty efficient.

Plus that whole it violates federal law to remove em thing.

Joe Z

iTrader: (10)

To answer your question...

(Connect the lines)

This below layout will not be effecient for gains...

l l
X
Y
l l

This lay out will..

l l
X
l l
l l

suicidesam

nice...i would like to do this mod and eliminating the "y" pipe the hks hi power connects too

gc86

iTrader: (26)

Thanks for the info fellas, that makes enough sense as well, JoeZ

Now I'm thinking about cutting up my stock midpipe and tanabe to create a true dual setup... :\

dblockjr

I did it to mine with 2.25" 304ss true dual all the way from primaries with magnaflow mufflers, with an x-pipe in place of secondaries. I love it, and it sounds pimp!